Chapter 3 of 15 · 23775 words · ~119 min read

PART 1

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INTRODUCTION

=1. Scope of Subject.=—The art of estimating is very important both to the architect and to the builder; to the latter, in that he must employ some systematic method of estimating in order to carry on his business successfully, and to the former for the reason that he should at all times be able to estimate the cost of the buildings that he designs.

The science—for such it is—of fixing prices on a piece of work in any branch of the building trades must be based on an extended experience. With a little practice, any one can learn to take off the quantities of materials, but when it comes to determining the rates, only persons having extensive and varied knowledge of building and costs of various details can accurately estimate the time and labor required to complete the work. In order, then, that the duties and requirements of a practical estimator may be thoroughly understood, a number of detailed estimates will be given in this Section as guides. It should be remembered, however, that as the prices of materials and labor vary from those assumed, so will the estimates vary. The information given in detail should be considered only as a general guide in analyzing the elements that enter into the constructive problems in each department of the building trades. In this way it will be possible to determine intelligently the various unit costs. The estimates given are, in general, net figures, and do not include any contractor’s profit.

=2. Qualifications of the Estimator.=—In the United States, there are no standard or definite rules on estimating that hold good in every section. The builders of each locality have their own ideas and customs regarding the subject. This fact, together with the difference in the cost of labor in various parts of the country and the fluctuations in the market price of materials, requires, as before remarked, that a competent estimator be a man of long and varied experience in the business. There are, however, certain practical rules and suggestions that will materially assist in taking off the quantities and in valuing the labor required for any building operation. These points will therefore be taken up and considered in detail in this Section.

=3. Important Factors.=—The prime considerations in making an estimate are accuracy and time. To these ends the estimator must systematize his efforts, and endeavor to do a maximum amount of work in a minimum amount of time. This, however, should not be done at the expense of accuracy, for accuracy is the most important factor and is only insured when the figures are carefully checked. The estimator, therefore, while avoiding too great refinements in calculation, should aim at correctness rather than at speed in doing the work. Very frequently do the effects of haste and inaccuracy in estimating the cost of a structure become evident when it is too late to remedy the errors, resulting sometimes in the financial ruin of the builder that trusts too implicitly in the estimator’s figures.

A record should be kept of all estimates made, as this kind of information is most valuable and establishes a precedent on which to base subsequent estimates, as well as a check on the work at hand.

PRINCIPLES OF ESTIMATING

APPROXIMATE ESTIMATING

=4.= In order to make a preliminary estimate, before the plans of a structure are drawn, but after the general dimensions of the proposed building have been determined, architects and builders sometimes employ a method of =approximate estimating=, by which the cost is figured at so much per cubic foot of the building, the rate varying according to its character and the finish required. The method is also considerably used by insurance companies in fixing the amount to be placed on a building. It should be borne in mind that this method gives the approximate cost only, and should never be used in figuring the contract price of a building. This estimate, however, may be used to advantage in checking the accurate estimate, with which it will frequently be found to agree remarkably well.

TABLE I

COST OF BUILDINGS PER CUBIC FOOT

Table I shows the approximate cost per cubic foot of various kinds of structures. In computing the contents of a building, there is no uniformity in practice, but no great error will be made in figuring the solid contents from floor of cellar to ridge of roof.

OUTLINE OF THE WORK

=5.= The drawings and specifications of a structure are the guides that the estimator must follow in making his computations. All measurements necessary for calculating the quantity of the materials required are obtained from the drawings; and all information in regard to the character of the workmanship and the quality of the materials to be used is furnished by the specifications.

In compiling a schedule, there are three stages to the operation: (1) Taking the dimensions for each of the various classes of work; (2) computing and collecting the quantities; and (3) estimating the cost.

In carrying out the first of these steps, each of its subdivisions should be considered in the order in which the work will be executed in the building. This order is about as follows:

1. Excavation 8. Joinery 2. Concrete work 9. Hardware and ironwork 3. Stonework 10. Heating and ventilation 4. Brickwork 11. Plumbing and gas-fitting 5. Carpentry 12. Painting and papering 6. Roofing 13. Glazing 7. Plastering

The third step, estimating the cost, may be subdivided into cost of labor and cost of material. The latter can be definitely fixed by an examination of lists giving current prices of materials; while the former must be based on a fixed rate of wages per day for the various classes of workmen.

The second and third branches of the work, being closely connected with the first, will be partly considered in connection with it, and, later, in detail in the complete example on estimating.

ACCURATE ESTIMATING SCHEDULE

=6.= There are so many items to be considered in a careful estimate, that the estimator should have a list of those coming under each of the main headings already given, and in compiling a schedule he should follow this order. The following list, which is arranged to assist in making an estimate on a dwelling house, will serve as an example of the general method that should be adopted:

EXCAVATION

Cellar Wells Areas Pipe trenches Piers Fence trenches Privy vaults Grading Footings Filling Cesspool Labor Catch basins

CONCRETE WORK

Cement Wells Sand Area walls Broken stone Chimneys Form lumber Footings Foundation walls Floors Partition walls Columns Piers Pavements Exterior walls Fences Concrete blocks Hearths Concrete cornices Steel reinforcement Core walls Anchor bolts Backing Nails and spikes Cesspools Labor Tanks

STONEWORK

Lime Wells Cement Chimneys Sand Footings Mortar Cut or dressed stonework Foundation walls Carved stonework Exterior walls Pavements Partition walls Stone fences Piers Stone hearths Area walls Anchors and bolts Cesspools Labor

BRICKWORK

Lime Cesspools Cement Wells Sand Range setting Mortar Furnace setting Foundation walls Footings Exterior walls Chimneys Partition walls Trimmer arches Piers Brick hearths Area walls Pavements Terra-cotta work Fences Tiling Labor

CARPENTRY

FRAMING

Girders in cellar Joists, first story Sills Joists, second story Cross-sills Joists, third story Posts Joists, attic story Beams Ceiling beams Girts Headers Studs Trimmers Plates Common rafters Deck plates Hip rafters Tower plates Valley rafters Braces Purlins Joists, basement Furring Ridge pole Carrying beams Collar beams Ironwork Lintels Rods and bolts Framing piers Nails and spikes Outlookers Labor

COVERING

Sheathing lumber Flooring Sheathing paper Corner boards Base Casings Siding Cornice Shingles Labor

ROOFING

Tin Gutter linings Shingle Solder Slate Cresting Tile Finials Paper or felt Conductor hooks and fastenings, Hanging gutters nails and hooks Conductor pipes Cast shoes or boots Conductor heads Labor Flashings

PLASTERING

Lath Three-coat work Lime Plaster board Sand Patent plaster Hair Tiling, marble, etc. Plaster of Paris Stucco cornices Plastering mortar Stucco arches Deafening Stucco centers Back plastering Nails One-coat work Labor Two-coat work

JOINERY

INSIDE AND OUTSIDE FINISH

Window frames Doors Door frames Base Sashes Architraves Corner and plinth blocks Posts Outside and inside blinds Columns Brackets Balusters Wainscoting Hand railing Moldings Nails and screws Planed lumber Labor

STAIRS

Rough lumber Hand railing Treads and risers Balusters Strings Brackets Spandrels Bolts Moldings Nails and screws Newels Labor

HARDWARE

Mortise locks Sash lifts Rim locks Sash cord Padlocks Transom lifters Butts (various sizes) Cupboard catches Wrought butts Hooks and eyes Strap hinges Drawer pulls Blind hinges Mortise bolts Sash fasteners Door stops Sash weights Door hangers Shutter bars Axle pulleys

HEATING AND VENTILATING SYSTEM

HOT-AIR HEATING

Furnace Registers Cold-air ducts and slide Sheet-tin and asbestos dampers fire protection Hot-air pipes, elbows, and dampers Smoke pipe Register boxes Labor

STEAM HEATING

Boiler Smoke pipe Regulating and safety Steam pipes appliances Return pipes Fittings Galvanized sheet-iron casings Hangers for indirect stacks Indirect, direct-indirect, Sheet-iron indirect flues, screens, and direct radiators and dampers Valves Indirect registers and boxes Air vents Japanning and bronzing Floor and ceiling plates Pipe coverings Labor

HOT-WATER HEATING

Heater Automatic damper regulator Smoke pipe Expansion tanks Radiators, pipes, fittings, etc., same as for steam heating Labor

PLUMBING AND GAS-FITTING

PLUMBING FIXTURES

Kitchen range with water-back Kitchen sinks Plunge baths Pantry sinks Shower baths Slop sinks Foot baths Laundry tubs Sitz baths Safes Wash basins Hot- and cold-water faucets Water closets for fixtures Urinals Labor

WATER SUPPLY

_City Supply_ Pumps Permits Supply tanks Corporation connections Outside piping Excavation Lawn and garden hydrants Extra-heavy lead, iron or Fittings, etc. brass service pipe Wrought-iron pipe fittings Curb cock and box Brass pipe fittings Stop and waste Lead pipe fittings

_Well Supply_ Solder nipples Storage cisterns Stop-cocks Cistern filters Pipe straps Metal tacks Wiping solder Kitchen boiler and stand Labor

HOUSE DRAINAGE

Permits Lead soil, waste, Sewer connections and vent pipes Excavations Lead traps Vitrified sewer pipe Brass traps and fittings Fixture connections (brass) Earthenware traps Wrought-iron, galvanized, or Portland cement asphalt-coated drain, soil, Unglazed drain pipe and vent pipes and fittings Cast-iron soil pipe and Fresh-air inlets, vent caps fittings Vent-pipe flashings Lead and oakum Wall hooks, straps, bands, Cast-iron traps and hangers Handholes and cleanouts Wiping solder Lead bends, brass ferrules Labor

GAS-FITTING

Permit Chandeliers Tapping main Pendants Excavation Wall brackets Meters Pillar lights Stop-cocks Globes, shades, and fireguards Drip cups Gas stoves and ranges Piping Gas-heater connections Straps and hangers Labor Fittings Pressure regulators

PAINTING AND PAPERING

PAINTING

Body of house Floors Trimmings Ceilings Blinds Walls Roof Sash Porches Shelving Inside work Mantels Oiling Fences Polishing Outbuildings Varnishing Labor

PAPERING

Paper Lining paper Borders Labor

GLAZING

Sheet glass Ribbed glass (single or double thick) Frosted glass Plate glass Glaziers’ points Leaded glass Putty (stained or clear) Labor

EXCAVATION

=7. Excavation= is generally measured by the cubic yard, although, in a few localities, measurement by the perch is still in use. If the latter method is adopted, it should be stated just what is meant by a perch, as this varies considerably in different parts of the country.

Before fixing the price for excavation, it is advisable to investigate the character of the soil by making boring tests. Where there is rock to be blasted in making the excavation, a special price should be given in the estimate. If the ground is wet, rendering pumping necessary, provision should be made for the cost of the extra labor needed. The disposition to be made of the excavated material should also be considered; if it must be hauled a long distance, the cost will be much greater than if the soil can be _wasted_ near by. To aid in estimating the actual cost, it is convenient and approximately correct to consider 1 cubic yard of ordinary earth as a load for an ordinary two-horse wagon.

In making calculations of the amount of material to be removed, care should be taken to note the existing levels of the ground and those required by the drawings. The excavation should be figured (and made) at least 1 foot greater than the size of the foundation, so as to provide room for setting the masonry, pointing, etc.

Excavation for pipes, drains, etc. should be at least 9 inches wider than the diameter of the pipe to be laid therein. If the soil in which the excavation is to be made is of a loose and sandy nature that is liable to crumble and slide, a slope, say of 3 inches horizontal to 1 foot vertical, should be allowed on both sides of the trenches. If the latter are of considerable depth, it is sometimes necessary to curb or shore up the sides, in which case an allowance should be made in the estimate for the lumber required. If piles are required, they should be figured at so much per linear foot, driven.

ACTUAL COST OF EXCAVATION

=8.= In order that an idea may be formed of the actual cost of excavating various kinds of soils, figures based on work actually performed are here given. On this work, for a day of 8 hours, a laborer was paid $2, and a driver with a two-horse team, $4.

As a rule, one laborer can excavate about 7 cubic yards of sandy soil in 8 hours. Thus, at the rate of 25 cents per hour, the cost of excavating this kind of soil is about 28½ cents per cubic yard, provided the material is wasted around the building. To this figure, however, must be added 4 or 5 cents to cover the foreman’s wages, the exact amount depending on the number of men under the foreman. This brings the total cost per cubic yard to about 33 cents.

When the material has to be carted away, the cost is further increased. A team with a driver can haul away about 20 cubic yards of soil in a day if the haul is only about ½ mile. In order to do this, however, an extra wagon must be at hand so that the laborers can be loading one wagon while the team is hauling away the other. Thus, the cost of hauling 1 cubic yard of excavated material ½ mile is 20 cents. The total cost, therefore, of excavating 1 cubic yard of sandy soil and hauling it ½ mile is 33 + 20 = 53 cents.

=9.= If the soil is compact gravel, the cost of excavating, including the foreman’s time, will be from 34 to 65 cents per cubic yard, depending on its hardness. It costs about the same to haul compact gravel as it does to haul sandy soil.

The exact cost of excavating wet soil cannot be given, as the conditions encountered may vary in each case. In a stated time, a laborer will excavate nearly as much wet material as dry material, but the conditions of sheet piling and pumping out water makes the price uncertain.

Such excavation is usually carried on at a cost of from 75 cents to $1.25 per cubic yard.

In excavating rock, three men—one rockman and two laborers—usually work together. For a day of 8 hours, the rockman receives $3 and each laborer gets $2. Together, therefore, the wages of the three amounts to $7 a day. These men will excavate about 6 cubic yards of rock in 1 day, making the rock excavation cost $1.17 per cubic yard. To this must be added the cost of explosives, which is about 10 cents per cubic yard, and the wear on tools. This latter expense can hardly be estimated, but may also be considered as 10 cents per cubic yard, thus bringing the total cost of rock excavation up to $1.37 per cubic yard for rock wasted at the building.

=10.= To sum up, excavation in sandy soil wasted around the building costs 33 cents per cubic yard; if hauled ½ mile, it costs 53 cents per cubic yard. If the soil is compact gravel and is wasted around the building, excavation costs from 34 to 65 cents per cubic yard; if hauled ½ mile, from 54 to 85 cents per cubic yard. Wet excavation with no piling or pumping costs about the same as dry; with piling and pumping, it costs from 75 cents to $1.25 per cubic yard. Rock work costs $1.37 per cubic yard if wasted around the building. These figures do not include the contractor’s profit.

CONTRACTOR’S METHOD OF FIGURING EXCAVATION

=11.= Besides the actual cost of excavation, the contractor, in estimating, must include such items as office expenses, builder’s profits, etc. The following method of figuring, which is employed by the estimator of a large contracting firm in the eastern part of the United States, will therefore be found useful. As in the preceding case, the prices will be found to vary in different localities; therefore, the figures given should only be used as a guide in estimating.

The prices are based on labor at $2 per day of 8 hours and a two-horse team and driver at $5 per day of 8 hours. The excavation is assumed to be made in ground varying from made ground to a moderately stiff clay. The prices do not include the cost of shoring or pumping, and are based on the assumption that there is no frost of any account while operations are being carried out. Four classes of excavation are recognized:

1. Excavation in trenches up to 5 feet deep, excavated material spread on site about trenches, including back filling around walls, costs from 40 to 50 cents per cubic yard.

2. Trenches from 5 to 10 feet deep, excavated material spread on site adjacent to trenches, including back filling around walls, costs from 65 to 75 cents per cubic yard.

3. For cellars, or similar digging, up to 6 feet deep and having an area large enough to use a plow for loosening the earth (say areas 50 ft. × 20 ft. and over), excavated material being spread on site adjacent to work, costs from 33 to 38 cents per cubic yard if a scoop can be used, and from 40 to 45 cents per cubic yard if the material must be loaded on a wagon to haul it out of the excavation.

4. When the conditions are the same as those just given, except that the excavation is from 6 to 10 feet deep, the price is about 45 cents per cubic yard.

The prices just given do not include hauling, except short hauls immediately in the vicinity of the operations. The cost of hauling will depend on the distance to the place where the material is to be dumped.

=12.= To obtain the cost of any of the classes of excavation just given, including hauling, divide the hire of the team per day by the number of cubic yards that can be removed to the dumping place per day, and increase the preceding prices by that amount.

To figure the cost of sheet piling, measure the area to be sheet-piled and allow for such stringers and braces as judgment may suggest. Since the lumber may be used for other purposes after serving as piling, its value should be estimated at 75 per cent. of the market price. It usually costs about $7 per thousand feet to put the piling in place. As a rule, 3" × 10" planks are used for this purpose.

The foregoing prices cover the general run of building work. For large office buildings and other structures of a similar nature, where it is necessary to excavate to a depth of about 25 feet and where several varieties of ground are likely to be encountered, an average price for digging (exclusive of pumping or shoring, but including a haul not exceeding 1 mile) is $1.25 per cubic yard. If large boulders are likely to be encountered in excavating, the price should be at least $1.50 per cubic yard.

DITCH WORK

=13.= In estimating the cost of =ditch work=, there are several factors that influence the price. A narrow ditch costs more to dig per cubic yard than a wide one; likewise, a deep ditch costs more than a shallow one. Following are given prices for laying agricultural drain tiling. While these figures do not include builder’s profit, they are based on the actual cost of work, the wages for a day of 8 hours being $2 for laborers, $2.50 for the foreman, and $4 for a horse and driver. In sections of the country where higher wages are paid, it will be necessary to increase the figures at a proportional rate when making estimates.

For trenches 3 feet deep and 18 inches wide, in very hard, clay soil with about 10 inches of loam on top, the cost of excavating is about 12 cents per linear foot, or 72 cents per cubic yard. For filling in the trench with the aid of a team and a scraper, it costs ¾ cent per linear foot. For laying a 4-inch tile, including distributing along the trench, the cost is ¾ cent per linear foot. For picking stones off of the ground and placing them over the pipe to a depth of about 8 inches, it costs 2¼ cents per linear foot. Each outlet built of field stones laid in cement costs from $5 to $8.

CALCULATING THE VOLUME OF AN EXCAVATION

[Illustration: FIG. 1]

=14.= The ordinary rules of mensuration are all that are needed to compute the =volume= of any excavation. The work is very simple when the area to be removed is regular; but when the outlines are very irregular and broken, the easiest method to employ in calculating the excavation is to divide the plan into geometrical figures that are easy to compute, and then calculate the area of each one separately. Adding these areas and multiplying their sum by the depth of the cellar will give the volume of the excavation.

This method will be made clear by referring to Fig. 1, which represents the plan of an irregular foundation. To compute the area of the excavation, the plan is divided into the rectangles _a d c b_, _l k b m, j i h g, g f e c_, and the polygons _n q p o, t u r s_, and _a x w v_. By scaling on the drawing the dimensions of these figures, the area of each may then be readily determined by calculation.

[Illustration: FIG. 2]

=15.= It is sometimes necessary to find the volume of an excavation, the surface of which is very irregular, as in Fig. 2. In such a case, the following method may be used: Divide the surface of the excavation into a number of squares, or rectangles, as at _d e f c_; these represent the ends of prisms, the other ends of which are the bottom of the excavation, as at _a h g b_. Then calculate the volume of each prism by ascertaining the height of the four corners above the bottom; add these measurements together, divide the sum by 4 (the number of corners), and multiply the result by the end area, as _a h g b_; the product will be the volume of the prism. The sum of these partial volumes will be an accurate estimate of the contents of the excavation.

CONCRETE WORK

=16. Plain concrete work= is usually paid for by the cubic yard. The contractor furnishes all material, including the lumber, to make the forms; he also erects the forms and removes them after the concrete has been placed. There is no fixed practice regarding openings in walls. Usually, small openings under, say, 100 square feet in superficial area are considered as solid. All larger openings are deducted from the work when measuring for payment. In some localities, the actual volume of the concrete work is taken by the contractor as a basis of the cost. In either case, it is of prime importance that the architect and the contractor make some distinct agreement _beforehand_ as to exactly how the concrete work is to be measured and paid for.

=Reinforced-concrete work= is also often measured by the cubic yard, although sometimes it is contracted for as a finished building. The steel reinforcement is sometimes included in the price. Often, patented steel reinforcement is bought separately and delivered to the contractor; at other times, the contractor buys the patented steel or else makes it and pays a royalty to the holder of the patent. Reinforced-concrete floors are sometimes measured by the cubic yard and sometimes by the square yard, according to agreement. Pavements are usually measured by the square foot or by the square yard.

In Table II are given the costs of stone concrete and gravel concrete. These figures do not include builder’s profit, cost of superintendence, or cost of forms. They are based on the following costs: Labor, 25 cents per hour; cement, $2 per barrel; sand, $1.50 per cubic yard; crushed stone, $1.65 per cubic yard; gravel, $1 per cubic yard.

To the values given in the table, the price of the wooden forms, both for material and erection, must be added. This of course varies considerably, according to whether the work is straight or has a number of corners and openings in it.

TABLE II

COST OF PLAIN STONE CONCRETE ===================+===================+=============================== Mixture | Quantity | Cost ------+-----+------+------+-----+------+------+-----+------+-----+----- Cement|Sand |Broken|Cement|Sand |Broken|Cement|Sand |Broken|Labor|Total Parts|Parts| Stone| Bar- |Cubic| Stone| | | Stone| | | | Parts| rels |Yards| Cubic| | | | | | | | | | Yards| | | | | ------+-----+------+------+-----+------+------+-----+------+-----+----- 1 | 2 | 4 | 1.5 | .45 | .90 |$3.00 |$.68 |$1.49 |$.75 |$5.92 1 | 3 | 5 | 1.1 | .50 | .85 | 2.20 | .75 | 1.40 | .75 | 5.10 1 | 3 | 6 | 1.0 | .45 | .90 | 2.00 | .68 | 1.49 | .75 | 4.92 ------+-----+------+------+-----+------+------+-----+------+-----+-----

COST OF PLAIN GRAVEL CONCRETE -------------------+-------------------+------------------------------ Mixture | Quantity | Cost ------+-----+------+------+-----+------+------+----+------+-----+----- Cement|Sand |Gravel|Cement|Sand |Gravel|Cement|Sand|Gravel|Labor|Total Parts|Parts|Parts | Bar- |Cubic|Cubic | | | | | | | | rels |Yards|Yards | | | | | ------+-----+------+------+-----+------+------+----+------+-----+----- 1 | 2 | 4 | 1.3 | .4 | .80 |$2.60 |$.60|$ .80 |$.75 |$4.75 1 | 3 | 5 | 1.0 | .5 | .80 | 2.00 | .75| .80 | .75 | 4.30 1 | 3 | 6 | .9 | .4 | .85 | 1.80 | .60| .85 | .75 | 4.00 ======+=====+======+======+=====+======+======+====+======+=====+=====

The price of forms, including both material and erection, may be said to vary from 50 cents for ordinary cellar work to $2 for heavy retaining walls per cubic yard of concrete placed.

DATA ON REINFORCED-CONCRETE BUILDING

=17.= The cost of =reinforced-concrete buildings= varies with the market price of cement and the steel bars or metal used for reinforcing. At present, reinforced-concrete buildings of the factory type constructed of common, hard, stretcher-brick walls and reinforced-concrete floors, roof, and columns with foundations may be built for from $1.35 to $1.65 per square foot of floor area. Usually, the height of ceilings in factory buildings is about 14 feet from floor to floor, thus making the cost of this type of building approximately from 10 to 12 cents per cubic foot. For buildings of a better commercial type, with face-brick walls and terra-cotta trimmings, the cost per square foot of floor area will range from $1.65 to $1.90, making the cost per cubic foot from 12 to 14 cents.

Reinforced-concrete buildings, as a rule, exceed the cost of buildings of slow-burning construction of the same size by an amount about equal to the cost of the metallic reinforcement. In other words, a building of reinforced concrete costs from 10 to 25 per cent. more than the same building of slow-burning construction.

The price of reinforced concrete per cubic yard varies within wide limits, depending on the mass of concrete employed and the intricacies of the forms. In building construction, reinforced concrete, including the price of the forms, can usually be placed for from $12 to $18 per cubic yard, the cost of the steel reinforcement being added.

Where the building is of considerable height, the same forms used in the three lower stories may be used in constructing the balance of the building. In such a case, the cost of the forms will probably not exceed $6 for each cubic yard of concrete placed. If the building is only two or three stories in height, and the work is rushed by using new centering in each floor, the cost of the forms will range from $7 to $9 per cubic yard of concrete.

The cost of form work for floor construction will range from 10 to 12 cents per square foot. Column forms will cost in the neighborhood of 20 or 25 cents per running foot. The forms used for fine concrete-wall construction require considerable time and bracing, and generally must be executed with great care where finished work is required. Such forms will cost from 8 to 10 cents per square foot of form on both sides of the wall, but will greatly exceed this price if molded courses or paneled spandrels are to be formed and lettering is to be cut in the work.

=18.= In estimating the cost of =reinforced-concrete slabs=, the cost of the centering, the concrete, and the steel reinforcements must be considered. The cost of centering for slab work varies from 5 to 7 cents per square foot, the latter figure probably being more nearly correct for usual conditions. The concrete for plain reinforced-concrete slab construction on steel beams can be placed for about $5.60 per cubic yard, or 1¾ cents for a square foot 1 inch in thickness. At present market values, the steel for reinforcing slabs can usually be considered as costing about 3 cents a pound, the pound price increasing as the rods decrease in size.

Table III gives the approximate cost, in cents per square foot, of constructing different thicknesses of reinforced-concrete slabs on steel-beam construction with the different sizes of reinforcing bars usually employed. The prices include cost of centering, concrete, and steel reinforcement.

=19.= Table III cannot be used for estimating the cost of a reinforced-concrete floor with reinforced-concrete beams and girders. In the construction of such a floor, the centering is much more costly than where steel beams are used for the support of the floor slab. On an average, the centering for the reinforced-concrete floor systems, including the studding and shoring, will cost from 20 to 22 cents per square foot, the sides of the beam and girder forms being included in the square-foot estimate. This cost is materially reduced where the centering is used over and over again for the construction of upper floors, so that where the building is six or eight stories in height, the average cost of the centering will not exceed 10 or 12 cents per square foot, including shoring, as just mentioned. Owing to the difficulty encountered in placing the concrete in the beams, the tamping required with slice bars, etc., and the expense of placing the reinforcement, the concrete for such construction will cost about $7.50 or $8 per cubic yard. The steel for the entire construction will usually average from 3 to 4 cents a pound, depending on whether plain rods or deformed bars are used, or whether the system is made up of loose rods or fabricated frames. In estimating the cost of such a floor system, the centering should be figured by a carefully itemized estimate, or roughly from the preceding figures. The amount of concrete in both the slab beams and columns should be estimated, and the total number of cubic yards required for the entire work should be determined; then the unit price for providing and placing the concrete should be carefully considered with reference to local conditions of labor and cost of material.

TABLE III

COST IN CENTS PER SQUARE FOOT OF REINFORCED- CONCRETE FLOOR SLABS SUPPORTED ON STEEL BEAMS =========+=========+========+=========+========+======== Thickness|⁵/₁₆-Inch| ⅜-Inch |⁷/₁₆-Inch | ½-Inch |⅝-Inch of Slab |Diameter |Diameter|Diameter |Diameter|Diameter Inches | Rods at |Rods at | Rods at |Rods at |Rods at | 6-Inch | 6-Inch | 6-Inch | 6-Inch | 6-Inch | Centers |Centers | Centers |Centers |Centers ---------+---------+--------+---------+--------+-------- 3½ | 14.87 | 15.58 | | | 4 | 15.75 | 16.46 | 17.24 | | 4½ | 16.62 | 17.33 | 18.11 | 18.87 | 5 | 17.50 | 18.21 | 19.00 | 19.75 | 20.87 5½ | 18.37 | 19.08 | 19.87 | 20.62 | 22.62 6 | 19.25 | 19.96 | 20.75 | 21.50 | 23.50 =========+=========+========+=========+========+========

CEMENT CELLAR FLOORS

=20.= In determining the cost of =cement cellar floors=, the concrete proper and the top coat should be considered separately. The concrete proper is usually reckoned by the cubic yard. About 1 hour more is required to lay a cubic yard of floor than is necessary for plain concrete work. Therefore, in estimating, 25 cents per cubic yard, or the wages of a laborer for 1 hour, must be added to the figures given in Table II. A 1-3-6 mixture is generally used. For stone concrete, then, the cost of the concrete proper for a cement cellar floor would be $5.17 per cubic yard, exclusive of the cost of supervision and the builder’s profit.

An analysis of the cost per square yard of top coat 1 inch thick for a cement cellar floor is as follows:

Cost Cents

¼ hour, plasterer’s time, at 45 cents per hour 11¼ ¼ hour, laborer’s time, at 25 cents per hour 6¼ ¹/₁₅ barrel of cement, at $2 per barrel 13⅓ ⅛ barrel of white sand, at 75 cents per barrel 9⅜ ------ Approximate cost per square yard 40

To the foregoing should be added the cost of supervision and builder’s profit.

CONCRETE BUILDING BLOCKS

=21.= Concrete building blocks usually present about 2 square feet of surface in the wall and are generally 8 inches thick, thus making a volume of 1⅓ cubic feet. Since one-third of this volume as a rule is air space, the actual volume of concrete is a little less than 1 cubic foot. The materials in a block of this kind, if used in a 1-4 mixture, will cost about 18 cents. If the block is 12 inches thick instead of 8 inches, the materials will cost about half again as much, or 27 cents. The cost of labor to manufacture these blocks depends on whether they are made in great quantities, and the wages paid the workmen, etc., and varies from 6 to 10½ cents for each block. To lay a block in the wall costs from 5 to 10 cents, 7 cents being about the average price. This price includes the mortar used in laying. For teaming and haulage, an allowance of 5 cents per block is usually sufficient. The cost per block, 8 inches thick, set in the wall is then as follows:

MAXIMUM COST MINIMUM COST CENTS CENTS Materials 18 18 Labor 10½ 6 Placing 10 5 Haulage 5 none ------ ---- Total 43½ 29

These results divided by 2 will give the cost of the wall per square foot, since each block is supposed to have a surface of 2 square feet. If the wall is 12 inches thick instead of 8 inches, one-half as much again should be added to the price.

MASONRY

=22. Stone masonry= is generally measured by the perch; in some sections of the United States, however, measurement by the cord is preferred, but the best method (as being invariable) is by the cubic yard. In estimating by the perch, it is necessary to state how much the perch is taken at, whether 24¾ or 25 cubic feet. Note should also be made in regard to corners and deduction for openings. In most localities it is not customary to deduct openings under a certain size, and corners are usually measured twice.

=23.= Rough stone from the quarry is generally sold under two classifications; namely, _rubble_ and _dimension stone_. =Rubble= consists of pieces of irregular size, such as are most easily obtained from the quarry, up to 12 inches in thickness by 24 inches in length. Stone ordered of a certain size, or to square over 24 inches each way and to be of a particular thickness, is called =dimension stone=.

Rubble masonry and stone backing are generally figured by the perch or cubic yard. Dimension-stone footings are measured by the square foot unless they are built of large, irregular stone, in which case they are measured the same as rubble. Ashlar work is always figured by the superficial foot; openings are usually deducted, and the jambs are measured in with the face work. Flagging and slabs of all kinds, such as hearths, treads for steps, etc., are measured by the square foot; sills, lintels, molding, belt courses, and cornices, by the linear foot; and irregular pieces, by the cubic foot. All carved work is done at an agreed price by the piece.

DATA ON RUBBLE MASONRY

=24.= The following proportions and cost of materials and amount of labor required to lay 1 perch of rubble masonry are reasonably accurate, and will serve to give an idea of how to estimate such work. A perch of rubble masonry requires, approximately, 2,500 pounds of stone.

COST OF RUBBLE MASONRY _Using 1-to-3 Lime Mortar_ 1 perch of stone (25 cubic ft.) delivered at work $1.25 1 bushel of lime .25 ⅙ cubic yard of sand, at $1.50 per cubic yard .25 ½ day, mason’s labor, at $3.20 per day 1.60 ¼ day, helper’s labor, at $2 per day .50 ----- Total $3.85

_Using 1-to-3 Portland-Cement Mortar_ 1 perch of stone $1.25 ¾ barrel of Portland cement, at $2 per barrel 1.50 ¼ cubic yard of sand, at $1.50 per cubic yard .38 ½ day, mason’s labor, at $3.20 per day 1.60 ¼ day, helper’s labor, at $2 per day .50 ----- Total $5.23

To the preceding amounts should be added the cost of scaffolding and the builder’s profit. If the walls are over two stories in height, 60 cents per perch extra for hoisting should be added.

DATA ON FLAGSTONES AND CURBING

=25. Flagstones= for sidewalks, ordinary stock, natural surface, 3 inches thick, with joints pitched to line, in lengths (along walk) from 3 to 5 feet, will cost, for a 3-foot walk, about 11 cents per square foot (if 2 inches thick, 10½ cents); for a 4-foot walk, 12 cents; and for a 5-foot walk, 16 cents. The cost of laying all sizes will average about 3 cents per square foot. These figures do not include cost of hauling.

Curbing, 4 in. × 24 in., granite, will cost from 40 to 50 cents per linear foot at the quarry; digging and setting will cost from 10 to 12 cents additional; and the cost of freight and hauling must also be added.

DATA ON ASHLAR AND CUT STONE

=26.= The following figures are average prices for =ashlar facing= when the transportation charges are not excessive, and are not given as fixed values, but more to show the relative costs. They include nothing but plain ashlar, and in estimating, the extra cost of sills, lintels, water-tables, belt courses, coping, etc. must be added. These prices are based on quarrymen’s wages of $2.50 per day, and stone-cutters’ wages of $4 per day.

Good rock-face bluestone ashlar, with from 6- to 10-inch beds, dressed about 3 inches from face, will cost, ready for laying, from 30 to 40 cents per square foot, face measure; while a higher grade of work will cost from 40 to 55 cents per square foot. Regular course bluestone ashlar, from 12 to 18 inches high and with from 8- to 12-inch beds, will cost about 50 cents per square foot. To this (and the previous figures) must be added the cost of hauling, which, on an average, will be about 3 cents per square foot.

To the preceding figures must also be added the cost of setting the ashlar. In estimating the cost of ashlar walls backed with brick, the wall is considered as solid brick, the cost of setting the ashlar being offset by the saving in cost of the brick and mortar and the labor resulting from making part of the thickness of the wall of stone. The cost of raking out the joints and pointing, which amounts to about 10 cents per square foot, must also be added.

=27.= The following figures show the approximate cost of cut bluestone for various uses:

Flagstone, 5-inch, size 8' × 10', edges and top bush-hammered, per sq. ft., face measure $ .75 Flagstone, 4-inch, size 5' × 5', select stock, edges clean cut, natural top, per sq. ft. .45 Door sills, 8" × 12", clean cut, per lin. ft. 1.35 Window sills, 5" × 12", clean cut, per lin. ft. .80 Window sills, 4" × 8", clean cut, per lin. ft. .45 Window sills, 5" × 8", clean cut, per lin. ft. .60 Lintels, 4" × 10", clean cut, per lin. ft. .65 Lintels, 8" × 12", clean cut, per lin. ft. 1.25 Steps, sawed stock, 7" × 14", per lin. ft. 1.10 Water-table, 8" × 12", clean cut, per lin. ft. 1.25 Coping, 4" × 21", clean cut, per lin. ft. 1.20 Coping, 4" × 21", rock-face edges and top, per lin. ft. .50 Coping, 3" × 15", rock-face edges and top, per lin. ft. .35 Coping, 3" × 18", rock-face edges and top, per lin. ft. .40 Platform, 6 inches thick, per sq. ft. .50

To the preceding prices of cut stone must be added the cost of setting, which for water-tables, steps, etc. will be about 10 cents per linear foot; and for window sills, etc., about 5 cents per linear foot. In addition, about 10 cents per cubic foot for fitting, and about 5 cents per cubic foot for trimming the joints after the pieces are set in place, should be allowed.

=28.= In a day of 8 hours, a stone cutter can cut about 4 square feet of granite, about 6 square feet of bluestone, or about 8 square feet of Ohio sandstone or limestone. These figures are for 6-cut, patent-hammered work. For rock-face ashlar (beds worked about 3 inches from face, the rest pitched), a workman can dress from 15 to 25 square feet of random ashlar per day; and from 18 to 20 square feet of coursed ashlar. In dressing laminated stone, from two to three times more work can be done in a day on the natural surface than on the edge of layers. In figuring cut stone, ample allowance should be made for waste, which, on an average, will be 15 per cent.

ADDITIONAL METHOD OF ESTIMATING ASHLAR

=29.= The following method of estimating the cost of cut stone is employed by many practical stone men. It is based on the fact that most ashlar walls have about the same number of sills, belt courses, lintels, water-tables, etc. in proportion to their volume, and therefore all the stonework, both the ashlar proper and the other cut stone, may be lumped together at one price per cubic foot. For estimating purposes, stone may be divided into two classes: _soft stone_, such as the sandstones, and _hard stone_, such as the granites.

=30. Soft Stone.=—Indiana limestone may be taken as an example of soft stone. In the Eastern Pennsylvania district, where the stone cutters’ wage rate is 50 cents per hour, the cost of this kind of stone is about as follows:

Rough blocks, per cubic foot $ .75 Sawing, jointing, cutting, rubbing, waste in stock 1.50 ----- Total $2.25

If the work is tooled, which is preferable for this material, 20 cents per cubic foot should be added. Thus the value in the yard, but ready to set, for an ashlar front, including water-table, sills, lintels, belt courses, all ordinary moldings, and plain cornices, is $2.45 per cubic foot.

Consoles, dentils, panelings, and similar ornamental work, mantels, and interior work have no fixed prices, but must be governed by the estimator’s knowledge of time required to cut any particular kind, sometimes reaching $5 per cubic foot. If moldings are deeply undercut, an extra price will have to be charged.

In heavy work, where the amount of stock is large compared with the amount of dressing, deductions may be made that sometimes amount to as much as 20 per cent. Rock-face work is somewhat more expensive than plain, dressed work because the projecting rock surface requires more stock; therefore, about 10 per cent. should be added.

It is customary to leave stone roughly cut to shape for carving in the wall, and therefore the sculptor determines the value from the drawings and includes the cost of models, which must be approved by the architect before the work is cut. Circular work, if plain, costs about the same as square work, but if fluted or reeded, as in the case of columns, it may cost as much as 50 per cent. additional.

=31.= Compared with limestone, the prices of other soft stones are as follows:

COST OF FOR CUTTING STOCK PER CENT.

Connecticut brownstone $1.25 20 Long Meadow brownstone 1.25 30 Portage red stone 1.05 30 Vermont or Georgia white marble 2.15 50 Pennsylvania blue marble 2.00 50 Bluestone .80 30

No definite price can be given for marble, as it comes in different grades and varieties.

The prices of stock just given are for stones of common size. If extra-large or extra-long stones are required, their price per cubic foot will be greater.

The cost of transportation from the quarries also influences the price of stone. This cost will vary according to the distance of the quarry from the location where the stone is to be used. The cost of hauling stone from the yard and setting it in the wall runs from 40 to 50 cents per cubic foot.

=32. Granite.=—Final estimates of cut granite by the cubic foot are seldom made, although approximate estimates are often made in that way by comparing a proposed piece of work with a similar one already completed. The reason for not making final estimates is that every additional molding or break in granite work affects the cost considerably, differing greatly in this respect from soft stone.

The first note to be made by the estimator is in regard to the cost of material. Good granite, in dimension sizes, can be obtained from southern quarries by rail for 65 cents per cubic foot, delivered. The same expenditure will buy very good eastern granite where through water transportation is available. If, however, the granite specified is such that it must be obtained from eastern quarries having only rail facilities for shipment, an addition of 40 or 50 cents per cubic foot will be required. There are also some special grades of granite that cost $1.50 or more per foot. In shipping granite, the railroads usually allow 8 cubic yards to the car. Granite for monumental purposes costs from $1.25 to $5 per foot, according to the size and quality. At wholesale, the price first mentioned, namely, 65 cents per cubic foot, will buy as good, substantial, and handsome material as will generally be required.

=33.= Machinery is used extensively for cutting plain faces in granite, and also to some extent for moldings and carved work. Every line in granite is costly to cut and must be computed separately. For instance, a plain face 12 inches wide, if cut by machinery, will cost 45 cents per square foot, while if cut by hand, where the machine cannot be applied, it will cost 60 cents. A 2-inch bevel, as shown at _a_, Fig. 3, will cost 50 cents per linear foot additional. A scotia, as shown at _b_, or other molding, as at _c_, will cost 60 cents per linear foot additional for each member.

[Illustration: FIG. 3]

All returns, no matter how small, must be counted as not less than 1 foot. Circular work costs from 50 to 100 per cent. more than straight work. Flutes or reeds in columns are very expensive, and must be calculated in each case according to the width and depth. All beads and joints should be counted at say 30 cents per square foot. All notches or rabbets are counted separately, according to shape and size.

The preceding prices are based on what is called patent-hammered, six-cut work. Eight-cut work will cost 15 per cent. more, and ten-cut work, which is seldom used in ordinary building work, brings $1 per square foot. Rock-face work in granite is cheaper than hammered work. A good, clean rock face should be counted at 20 cents per square foot. Axed, or peen-hammered, work is between rock face and six cut.

Polishing plain surfaces costs $1 per square foot in addition to the cost of cutting, surfaces having widths of 4 inches and under counting as 6 inches, and those over 6 inches up to 12 inches counting as 1 foot.

BRICKWORK

=34. Brickwork= is generally estimated by the thousand bricks laid in the wall, but measurements by the cubic yard and the perch are also used. The following data will be useful in calculating the number of bricks in a wall. For each superficial, or square, foot of wall 4 inches (the width of one brick) in thickness, allow 7½ bricks; for a 9-inch (the width of two bricks) wall, count 15 bricks; for a 13-inch (the width of three bricks) wall, allow 22½ bricks; and so on, estimating 7½ bricks for each additional 4 inches in thickness of the wall. The preceding figures are for bricks about 8½ in. × 4 in. × 2¼ in. in size. If smaller bricks are used, the thickness of the walls will be decreased proportionately.

If brickwork is estimated by the cubic yard, allow 500 bricks to a yard. This figure is based on the use of bricks of the size just given and mortar joints not over ⅜ inch thick. If the joints are ⅛ inch thick, as in face brickwork, 1 cubic yard will require about 575 bricks. In making calculations of the number of bricks required, an allowance of, say, 5 per cent. should be made for waste in breakage, etc.

The practice in regard to deductions for openings is not uniform throughout the United States, but, usually, small openings are counted solid, as the cost of the extra labor and the waste in working around these places balances that of the brickwork saved. All large openings, 100 square feet or over in area, should be deducted. When openings are measured solid, it is not customary to allow extra compensation for arches, pilasters, corbels, etc.

Rubbed and ornamental brickwork should be measured separately, and charged for at a special rate.

DATA ON BRICKWORK

=35.= The following estimates on the cost of brickwork are very carefully compiled, and will be found trustworthy. It should be understood that the prices will vary with the cost of materials and labor; the proportions, however, will be constant. The figures are based on _kiln_, or actual, count; that is, with deductions for openings. When the work is measured with no deductions for openings, the cost per thousand may be assumed as about 15 per cent. less than the prices given, which are exclusive of scaffolding, hoisting, and builder’s profit. The scaffolding will cost, according to conditions of the structure and site, from 5 to 7 per cent. of the prices given.

COST OF COMMON BRICKWORK PER THOUSAND BRICKS

_Using 1-to-3 Lime Mortar_ 1,000 bricks $8.00 2 bushels of lime, at 25 cents per bushel .50 ½ cubic yard of sand, at $1.50 per cubic yard .75 Bricklayer, 8 hours, at 55 cents per hour 4.40 Laborer, 8 hours, at 25 cents per hour 2.00 ------ Total $15.65

_Using 1-to-3 Portland-Cement Mortar_ 1,000 bricks $8.00 1 barrel of Portland cement 2.00 ½ cubic yard of sand .75 Bricklayer, 8 hours, at 55 cents per hour 4.40 Laborer, 8 hours, at 25 cents per hour 2.00 ------ Total $17.15

_Using 1-to-4 Lime-and-Cement Mortar_ 1,000 bricks $8.00 ¾ bushel of lime, at 25 cents per bushel .19 ½ cubic yard of sand .75 ⅔ barrel of cement, at $2 per barrel 1.34 Bricklayer, 8 hours, at 55 cents per hour 4.40 Laborer, 8 hours, at 25 cents per hour 2.00 ------ Total $16.68

COST OF STRAIGHT, PRESSED BRICKWORK, PER THOUSAND BRICKS

_Using Lime-Putty Mortar_ 1,000 pressed bricks, cost from $20 to $40 (average) $30.00 1½ bushels of lime .38 ¼ cubic yard of fine sand .38 Bricklayer, 27 hours, at 60 cents per hour 16.20 Laborer, 27 hours, at 25 cents per hour 6.75 ------ Total $53.71

ESTIMATING BRICKWORK

=36.= The following figures and method of estimating brickwork were supplied by an estimator of a large eastern contractor. The prices given include office expense and builder’s profit. The wages per hour on which these figures are based are: Bricklayers, 65 cents; hod carriers, 25 cents; and common laborers, 18 cents.

Following are mentioned four distinct classes of brick buildings, and in Table IV are given the labor prices per thousand brick for the various stories of buildings of these classes.

1. Absolutely plain factory buildings.

2. Factory or office buildings broken up with a few pilasters and other projections; stretcher-brick facing, neatly cleaned down and pointed.

3. Office buildings of fairly ornamental type, well broken up with pilasters, projecting courses, etc., with pressed-brick facing.

4. Highly ornamental brick buildings, molded cornices, pilasters, raised quoins, sunk molded panels, and numerous flat and segmental arches.

TABLE IV

LABOR PRICES PER THOUSAND BRICK FOR FOUR CLASSES OF BRICK BUILDINGS

=================+=========+=========+========+========= Part of Building | Class 1 | Class 2 | Class 3| Class 4 -----------------+---------+---------+--------+--------- Basement | $ 7.50 | $ 7.50 | $ 8.50 | $ 9.50 First floor | 8.00 | 9.00 | 10.50 | 13.50 Second floor | 8.50 | 10.00 | 11.00 | 14.00 Third floor | 9.00 | 10.50 | 11.50 | 14.50 Fourth floor | 9.50 | 11.00 | 12.00 | 15.00 Fifth floor | 10.00 | 11.50 | 12.50 | 15.50 Sixth floor | 11.00 | 12.00 | 13.00 | 16.00 =================+=========+=========+========+=========

The prices in the table include the cost of mortar. If the cost of brick at building is added, the result will be the total cost of brickwork exclusive of scaffolding. The average price of total brick labor in buildings of class 1 is $8.50; of class 2, $9.50; of class 3, $11.50; and of class 4, $14.

=37.= The following miscellaneous brick prices, including labor and mortar, but not brick, are from the same source as the prices given in the preceding article, and are based on the same condition, the prices being in bricks per thousand:

For heavy basement walls and similar masses of brickwork $ 7.00 For 18-inch brick walls not over two or three stories high, in hard brick with struck joints 8.00 Same as above, but for 13-inch walls 9.00 For 18-inch brick walls, as above, but faced on one side with pressed brick 12.00 For 18-inch brick walls, as above, but faced on both sides with pressed brick 16.50 For 13-inch brick walls, as above, but faced one side with pressed brick 14.00 For 13-inch brick walls, as above, but faced both sides with pressed brick 14.00 Add to above, if of English or Flemish bond, on entire cost of wall .50 If work is broken up into light piers, requiring a lot of plumbing, add to cost of wall as above 1.50 If a large number of segmental arches must be turned, add to total cost of wall 1.00

In addition to the preceding schedule two useful rules to remember are: For pressed-brick segmental arches, add for labor 1½ times the cost of bricks; for pressed-brick arches requiring radial brick, add for labor twice the cost of straight, pressed brick. As radial brick are shipped to the building in barrels and have to be unpacked and laid out on the full-sized diagram on the floor, it will be found that the rate given is not excessive.

For brick vault arches, the cost of labor, exclusive of mortar, will be about $5 per thousand brick. If pointed underneath, 7 cents per square foot will have to be added. If the centers are left in place until the mortar has set, it will be necessary to rake out the joints and wet them before pointing. This will cost about 10 cents per square foot.

TERRA-COTTA WORK

=38. Terra-Cotta Floor Arches.=—The cost of =terra-cotta floor arches= varies somewhat with the span and with the difficulties encountered in putting up and removing the centering. If the building consists of a number of stories, the centering that is used on one floor may be reused on a floor several stories higher up, in this way decreasing the outlay for centerings. For ordinary spans, the following analysis of the cost of a 12-inch arch, exclusive of the cost of the terra cotta itself, will be found quite accurate, provided the centering is put up by experienced laborers. The price given is per square foot of arch.

CENTS Centering 3 Hoisting and laying 3½ Mortar ½ ----- Total 7

This price is for work showing a flat ceiling. If the ceiling is much broken up by girders, the price, exclusive of the terra cotta itself, will be about 8 cents per square foot.

As a price per square foot, including the cost of terra cotta, setting, and mortar, the following figures may be taken. These, however, do not include the cost of plastering, or of any concrete fill above the terra cotta.

CENTS 10-inch arches 23 12-inch arches 25 15-inch arches 29

=39. Terra-Cotta Partitions.=—In office buildings, =terra-cotta partitions= are usually erected on top of a floor in order to divide the space into such rooms as will suit the tenants. This work is generally done after the building is otherwise completed. An analysis of the cost of such partitions is given in Table V.

TABLE V

COST OF TERRA-COTTA PARTITIONS =========+===============+=============+============== Thickness|Cost of Setting|Cost of Terra|Total Cost per Inches | per Square | Cotta per | Square Foot |Foot, Including| Square Foot | Cents | Mortar | Cents | | Cents | | ---------+---------------+-------------+-------------- 3 | 5 | 9 | 14 4 | 5 | 10 | 15 6 | 6 | 12 | 18 10 | 8 | 16 | 24 =========+===============+=============+==============

The cost of placing 8-inch, terra-cotta backing to brickwork is 6 cents per square foot.

TILING

=40.= Although not always of a brick or terra-cotta nature, it will be found more convenient to consider all =tiling= together and at the same time that the cost of brickwork is taken up.

Only very general figures can be given on the cost of tiling, as this cost depends considerably on the design to be carried out. The cost per square foot of various styles of tile laid in place is as follows:

Moravian tile floors $1.50 Interlocking, rubber tile floors 1.50 Columbia marble tile, 12" × 12", with colored border, tile laid straight on floor .50 Columbia marble tile, 12" × 12", with colored border, tile laid diagonally on floor .60 Italian marble tile, 12" × 12", with colored border, tile laid straight on floor .70 Italian marble tile, 12" × 12", with colored border, tile laid diagonally on floor .80 Terrazzo and marble mosaic border .38 to .40 Common, white tile in vertical locations, as lining for elevator shafts, etc. .40 Marble mosaic ceiling work 3.00 Marble and glass mosaic ceiling work 8.00 2-inch book tile (laying only) .04 3-inch book tile (laying only) .04 Shoe tile (laying only) .06

MACKITE

=41. Mackite= is a fireproofing material used for partitions in very much the same way as terra cotta. As this material is put in place by bricklayers, its cost will be taken up here.

Where there are many openings, two bricklayers and one laborer can set 240 square feet of mackite in 8 hours; in a straight wall, without openings, these same men can set about 400 square feet. The market price for 2" × 12" × 30" blocks is 6 cents per square foot; for blocks 3 inches thick, it is 8 cents per square foot. The average price for both material and labor for 2-inch mackite is 10 cents per square foot; for 3-inch material it is about 12 cents per square foot.

CARPENTRY

=42. Carpentry= should include general framing, roofs, floor joists, partitions, sheathing, flooring, furring, and plastering grounds.

=43. Board Measure.=—The rough lumber used in framing is measured by the =board foot=, which means a piece 12 inches square and 1 inch thick. Lumber is always sold on a basis of a thousand feet =board measure=. The customary abbreviation for the latter term is B. M.; that for _thousand_ is M. Thus, 500 feet board measure, costing $27 per thousand, would be written: 500 ft. B. M., at $27 per M.

To obtain the number of board feet in any piece of timber, the length, in inches, should be multiplied by the end area, in square inches, and the result divided by 144. For example, the number of feet B. M. in a floor joist 20 feet long, 3 inches thick, and 10 inches deep is 240 inches (=20 feet × 12) multiplied by 30 square inches (the end area) divided by 144, or 50.

The following rule is used by most contractors and lumber dealers: _Multiply the length in feet by the thickness and width in inches, and divide the product by 12._ Thus, a scantling 26 feet long, 2 inches thick, and 6 inches wide contains

26 × 2 × 6 ---------- = 26 feet B. M. 12

This rule, expressed in a slightly different manner, is more convenient for mental computation: _Divide the product of the width and thickness in inches by 12, and multiply the quotient by the length in feet._ Thus, a 2" × 10" plank, 18 feet long, contains

2 × 10 ------- = 30 feet B. M. 12 × 18

=44. Prices of Lumber.=—Owing to the continual variation in the prices and grades of lumber, it is impossible to give prices here that will not vary from day to day. The architect before starting to estimate should first be sure that he has the latest lumber prices obtainable. These prices can always be secured from the local lumber dealer.

=45. Studs.=—To calculate the number of =studs=—set on 16-inch centers—the following rule may be used: _From the length of the partition, in feet, deduct one-fourth, and to this result add 1. Count the number of returns, or corners, on the plan, where double studding is required, and add 2 studs for each such return._ (The reason for adding 1 is to include the stud at the end, which would otherwise be omitted.) The sills, plates, and double studs must be measured separately.

[Illustration: FIG. 4]

For example, the number of studs required for partitions only, shown on the plan, Fig. 4, is computed in the following manner.

30 ft. 6 in. 10 ft. 6 in. 9 ft. 6 in. 5 ft. 0 in. 4 ft. 6 in. ------------ 60 ft. 0 in.

Deducting one-quarter from 60 feet, the remainder is 45 feet; adding 1 stud, the result is 46 feet. As there are 4 returns, with 2 studs for each, as shown at _a a_, the total number is 46 + (4 × 2) = 54 studs.

As a general rule, when (as is customary) the studs are set at _16-inch_ centers, _1 stud for each foot_ in length of partition will be a sufficient allowance to include sills, plates, and double studs. Thus, if the total length of partitions is 75 feet, 75 studs will be sufficient for sills, double studs, etc. If the studs are set at _12-inch_ centers, the number required will be equal to the _number of feet in length of partition plus one-fourth_. Thus, if the length of partitions is 72 feet, 72 + 18, or 90, studs will include those required for sills, plates, etc.

The same rules may be used for calculating the number of joists, rafters, tie-beams, etc.

A good way to estimate bridging is to allow 3 cents apiece, or 6 cents per pair; this will be sufficient to furnish and set a pair made of 2" × 3" spruce or hemlock stuff.

=46. Sheathing.=—To calculate =sheathing= or =rough flooring= (not matched), find the number of feet B. M. required to cover the surface, making no deductions for door or window openings, because what is gained in openings is lost in waste. If the sheathing is laid horizontally, only the actual measurement is necessary; but if it is laid diagonally, add 8 or 10 per cent. to the actual area.

=47. Flooring.=—In estimating =matched flooring=, a square foot of ⅞-inch stuff is considered to be 1 foot B. M. If the flooring is 3 inches or more in width, add one-quarter to the actual number of board feet, to allow for waste of material in forming the tongue and groove; if less than 3 inches wide, add one-third. Flooring of 1⅛-inch finished thickness is considered to be 1¼ inches thick, and for calculating it the following rule may be used: _Increase the surface measure 50 per cent._ (This consists of 25 per cent. for extra thickness over I inch, and 25 per cent. for waste in tonguing and grooving.) To this amount add 5 per cent. for waste in handling and fitting.

In figuring the area of floors, openings for stairs, fireplaces, etc. should be deducted.

=48. Weather Boarding, or Siding.=—In measuring =weather boarding=, or =siding=, the superficial, or square, foot is usually employed. No deduction should be made for ordinary window or door openings, as these usually balance the waste in cutting and fitting. Careful attention must be given to the allowance for lap. If 6-inch, nominal width (actual width, 5⅝ inches), siding, laid with 1-inch lap, is used, add one-quarter to the actual area of the space to be covered, in order to obtain the number of square feet of siding required. If 4-inch stuff is used, add one-third to the actual area. When, as previously noted, no allowance is made for openings, the corner and baseboards need not be figured separately.

=49. Cornices.=—As a general rule, cornices are measured by the running foot, the molded and plain members being taken separately. A good method of figuring cornices is as follows: _Measure the girth, or outline, and allow 1½ cents for each inch of girth, per linear foot._ This price will pay for material and for setting, the cost of the mill work being estimated at 50 per cent.

=50. Cost per Square Foot.=—For all classes of materials that enter into the general framing and covering of a building, a close estimate may be made by analyzing the cost per square foot of surface; that is, the cost of labor and materials—studs and sheathing in walls, joists and flooring in floors, etc.—required for a definite area should be closely determined, and this cost divided by the area considered, will give the price per square foot. If the corresponding whole area is multiplied by the figure thus obtained, the result will, of course, be the cost of that portion of the work. While the usual custom is to adopt a uniform rate for the various grades of work, a careful analysis will show that roof sheathing, where the roof is much cut up, costs more in place than wall sheathing, owing to its position; also that the studs in walls and partitions cost more than floor joists, as they are lighter and require more handling.

The following example shows how to determine the cost per square foot of flooring and indicates the general method to be pursued in similar cases. The area used in the calculation is a square, or 100 square feet. The cost of labor is estimated at 40 per cent. of that of the materials, as it has been shown by experience that this allowance is a very close approximation to the actual cost of general carpenter work.

COST OF FINISHED FLOOR PER SQUARE Joists, hemlock, 8 pieces, 3" × 10" × 10', 200 feet B. M., at $27 per M. $ 5.40 Bridging, hemlock, 7 sets, 2" × 3" × 1' 4", 9 feet B. M., at $27 per M. .24 Rough flooring, hemlock, ⅛ inch thick, laid diagonally, 100 ft. + 25 ft. + 10 ft., 135 feet B. M., at $25 per M. 3.38 Finished flooring, No. 2, white pine, ⅞ inch thick, 125 feet B. M., at $45 per M. 5.63 Nails, eightpenny (about) 3 pounds, at $2.50 per 100 pounds .08 Labor, 40 per cent. of cost of materials 5.89 ------ Total cost for 100 square feet $20.62

Cost per square foot, $20.62 ÷ 100 = 21 cents.

A similar method may be followed in estimating the cost of interior finish, paneling, doors, etc.

=51. Work of a Carpenter per Day.=—The quantity of material that a workman can put in place in a day is very uncertain, as it depends on the skill of the man and the ease or difficulty of the work, both being somewhat modified by circumstances. The figures given in Table VI, while founded on information gained by many years of experience, are only intended to give an idea of the relative quantities and are not a standard to be adhered to in all cases. The estimates are based on an 8-hour day and wages at $3.20 per day. If the hours or pay are less or greater in various localities than the prices given, the results will be correspondingly diminished or increased.

TABLE VI

QUANTITIES OF MATERIAL PUT IN PLACE PER DAY BY ONE MAN ===================================+===========+==================== | Number of | Class of Material |Feet B. M.,| Remarks | or Number | -----------------------------------+-----------+-------------------- Studding 2" × 4", or 2" × 6" | 400 |Wall or partition. Rafters | 400 | Rafter ridge and bracing | 250 | Plate, 6" × 8", halved at corners | 350 | Floor joists, 2" × 10", or 3" × 12"| 500 | Ceiling joists, 2" × 6" | 450 | Sheathing, unmatched | 500 |Laid horizontally. Sheathing, unmatched | 400 |Laid diagonally. Sheathing, matched | 400 |Laid horizontally. Sheathing, matched | 300 |Laid diagonally. Sheathing, roof | 750 |Plain gable roof. | | | |Much cut up by hips, Sheathing, roof | 300 | valleys, dormers, | | etc. | | Ceiling lined with paper | 200 | | | | |Includes fitting Siding, 4 inches wide | 200 | and setting Siding, 6 inches wide | 300 | corner boards, | | base, trim, and | | scaffolding. | | | |Includes scarfing Posts and beams over cellars | 200-250 | and doweling. | | | |For base and | | wainscot, Plaster grounds, linear feet | 250 | straightened | | in good shape. | | Bridging, number of pairs per hour | 10 |Includes cutting | | and setting. | | False jambs around openings, | 1 | per hour | | ===================================+===========+========================

=52. Cost of Laying Flooring.=—The figures on flooring given in Table VII will be found useful in calculating as they are based on a square, which, as previously stated, is equal to 100 square feet. The same carpenters’ wages and number of working hours as in the preceding article are used here.

TABLE VII

=53. Miscellaneous Carpentry Items.=—In Table VIII is given the cost of several items of carpentry, such as setting window and door frames, furring brick walls, etc. The prices are based on the same wages and hours as in the two preceding articles.

TABLE VIII

=54. Nails.=—To calculate the quantity of nails required in executing any portion of the work, Table IX, which is based on the use of cut nails, will be found useful.

TABLE IX

QUANTITY OF NAILS REQUIRED FOR VARIOUS PURPOSES ======================================+========+================= Material | Pounds |Kind of Nails and |Required| Size in Pennies --------------------------------------+--------+----------------- 1,000 shingles | 5 | 4 1,000 laths, 4 nails to a lath | 7 | 3, fine 1,000 laths, 6 nails to a lath | 9 | 3, fine 1,000 sq. ft. beveled siding | 18 | 6 1,000 sq. ft. sheathing | 20 | 8 1,000 sq. ft. sheathing | 25 | 10 1,000 sq. ft. flooring, rough | 30 | 8 1,000 sq. ft. flooring, rough | 40 | 10 | | 1,000 sq. ft. studding | 15 | 10 | 5 | 20 | | 1,000 sq. ft. furring, 1" × 2" | 10 | 10 1,000 sq. ft. ⅞" finished flooring | 20 | 8 to 10, finish 1,000 sq. ft. 1⅛" finished flooring | 30 | 10, finish ======================================+========+=================

ROOFING

=55. Kinds of Roof Covering.=—The =roof coverings= most generally used are shingles, slate, tin, tile, and tarred paper and gravel (known as gravel roofing). While there are slight variations in the methods of measuring the different kinds, they are all based on the square of 100 square feet.

=56. Shingles.=—In measuring =shingle roofing=, it is necessary to know the exposed length of a shingle. This is found by deducting 3 inches (the usual cover over the head of the lowest shingle in the four overlapping courses) from the length and dividing the remainder by 3. Thus, in Fig. 5, the distance _b_ that one shingle is overlapped by the third above it is usually made equal to 3 inches, and the remaining length of the lowest shingle may be divided into three equal portions, each equal to _a_. The lowest of these three portions is the part exposed to the weather. Multiplying the length exposed to the weather by the average width of a shingle will give the exposed area. Dividing 14,400, the number of square inches in a square, by the exposed area of 1 shingle, in square inches, will give the number of shingles required to cover 100 square feet of roof. For example, it is required to compute the number of shingles 18 in. × 4 in. needed to cover 100 square feet of roof. With a shingle of this length, the exposure will be

18 - 3 ------ = 5 inches; 3

then, the exposed area of 1 shingle is 4 in. × 5 in., or 20 square inches, and 1 square requires 14,400 ÷ 20 = 720 shingles.

[Illustration: FIG. 5]

An allowance should always be made for waste in estimating the number of shingles required.

Table X is arranged for shingles from 15 to 27 inches in length, 4 and 6 inches in width, and for various lengths of exposure.

=57.= Shingles are classed as _shaved_, or _breasted_, and _sawed shingles_.

=Shaved shingles= have fallen almost into disuse, owing to the difficulty of manufacturing them. These shingles vary from 18 to 30 inches in length, and are about ½ inch thick at the butt and ¹/₁₆ inch at the top.

=Sawed shingles= are usually from 14 to 18 inches long and of various thicknesses. In the case of 18-inch shingles, five shingles, at their butts, will make 2¼ inches; that is, the thickness of one shingle at the butt is 2¼ ÷ 5 = .45, or about ⁷/₁₆ inch. At the top, each shingle is ¹/₁₆ inch thick. With 16-inch shingles, however, five of them make only 2 inches. Therefore, the thickness of a 16-inch shingle at the butt is 2 ÷ 5 = .4, or about ⅜, inch.

TABLE X

DATA FOR ESTIMATING SHINGLES ===========+===========================+=========================== | Number of Square Feet of |Number of Shingles Required Exposure to| Roof Covered by 1,000 | for 100 Square Feet Weather | Shingles | of Roof Inches +-------------+-------------+-------------+------------- |4 Inches Wide|6 Inches Wide|4 Inches Wide|6 Inches Wide -----------+-------------+-------------+-------------+------------- 4 | 111 | 167 | 900 | 600 5 | 139 | 208 | 720 | 480 6 | 167 | 250 | 600 | 400 7 | 194 | 291 | 514 | 343 8 | 222 | 333 | 450 | 300 ===========+=============+=============+=============+=============

White-pine and white-cedar shingles are graded alike. The shingles made of No. 1, or clear, stock are designated XXXX. Those made of No. 2 stock, with 6-inch clear butt, are given the brand XX, while those made of mill cull, with sound butt, are called X.

Red-cedar shingles are graded differently. Their grade depends on their length. Thus, 18-inch, No. 1 shingles are termed “Perfection,” while 18-inch, thin butt are termed “Eureka.” Red-cedar shingles 16 inches long, if made of No. 1, or clear, stock, are designated “Extra * A *.” If they are 16-inch, thin butt, they are termed simply “* A *.”

Sawed shingles are made up into bundles of 250, and are sold on a basis of 4 inches width for each shingle. Shingles cost from $4 to $6.75 per thousand, according to material and grade. Dimension shingles—those cut to a uniform width—if of prime cedar, shaved, ½ inch thick at the butt and ¹/₁₆ inch at the top, will cost about $7.75 per thousand, but since such shingles are usually 6 inches wide, less will be required per square.

A fairly good workman will lay about 1,000 shingles per day of 8 hours, on straight, plain work; while in working around hips and valleys, the average will be about 700 per day.

=58. Slating.=—In measuring =slating=, the method of determining the number of slates required per square is similar to that given for shingling; but in slating, each course overlaps only two of the courses below, instead of three, as in shingling. The usual lap, or cover, of the lowest course of slate by the uppermost of the two overlapping courses, is 3 inches; hence, to find the exposed length, deduct the lap from the length of the slate, and divide the remainder by 2. The exposed area is the width of the slate multiplied by this exposed length, and the number of slates required per square is found by dividing 14,400 by the exposed area of 1 slate in square inches. Thus, if 14" × 20" slates are to be used, the exposed length will be

20 - 3 ------ = 8½ inches; 2

the exposed area will be 14 × 8½ = 119 square inches; and the number per square will be 14,400 ÷ 119 = 121 slates.

The following points should be observed in measuring slating: Eaves, hips, valleys, and cuttings against walls are measured extra, 1 foot wide by their whole length, the extra charge being made for waste of material and the increased labor required in cutting and fitting. Openings less than 3 square feet are not deducted, and all cuttings around them are measured extra. Extra charges are also made for borders, figures, and any change in color of the work; and for steeples, towers, and perpendicular surfaces.

Table XI, which is based on a lap of 3 inches, gives the sizes of the American slates and the number of pieces required per square. The cost of slating varies from 9 to 15 cents per square foot, depending on the class of work.

The thickness of stock slate varies from five to 1 inch to ⅜ inch and special thicknesses up to 1 inch are made to order. For ordinary dwellings, the usual thickness used is five to 1 inch, which gives a thickness of a little more than ³/₁₆ inch, and the size used for this class of work is generally 8 in. × 12 in. or 9 in. × 18 in., the price being the same.

TABLE XI

NUMBER OF SLATES PER SQUARE ========+=========+=========+=========+=========+========= Size |Number of| Size |Number of| Size |Number of Inches | Pieces | Inches | Pieces | Inches | Pieces --------+---------+---------+---------+---------+--------- 6 × 12 | 533 | 9 × 16 | 246 | 14 × 20 | 121 7 × 12 | 457 | 10 × 16 | 221 | 11 × 22 | 138 8 × 12 | 400 | 9 × 18 | 213 | 12 × 22 | 126 9 × 12 | 355 | 10 × 18 | 192 | 13 × 22 | 116 7 × 14 | 374 | 11 × 18 | 174 | 14 × 22 | 108 8 × 14 | 327 | 12 × 18 | 160 | 12 × 24 | 114 9 × 14 | 291 | 10 × 20 | 169 | 13 × 24 | 105 10 × 14 | 261 | 11 × 20 | 154 | 14 × 24 | 98 8 × 16 | 277 | 12 × 20 | 141 | 16 × 24 | 86 ========+=========+=========+=========+=========+=========

In Table XII is given a list of the different colors of slate used in the Eastern and Middle States, the quarries from which they are obtained, and the cost of slate, labor, etc. per square, pertaining to each variety. The prices in the table are based on the 8 in. × 12 in. or 9 in. × 18 in. sizes, thickness five to 1 inch, and for quantities of not less than 50 squares. The cost of labor, etc. being based on current prices in the aforementioned territory.

Slate ¼ inch thick cost about 20 per cent. more than the five to 1 inch for the material, and about 5 per cent. more for laying and freight.

Slate ⅜ inch thick cost about 45 per cent. more than the five to 1 inch for the material, and about 15 per cent. more for laying and freight.

When copper nails are specified obtain current prices.

TABLE XII

APPROXIMATE COST OF SLATING, PER SQUARE ==================================+========+=========+============ | | Cost of | |Cost of | Laying, | Total Cost, Classification | Slate |Including| Exclusive |F. O. B.| Roofing |of Builder’s |Quarries|Felt, and| Profit | | Freight | ----------------------------------+--------+---------+------------ _Black Slate_ | | | Brownville, Maine | $8.00 | $5.00 | $13.00 Monson, Maine | 7.00 | 5.00 | 12.00 Peach Bottom, Pennsylvania | 5.50 | 4.00 | 9.50 Chapman (Hard Vein), Pennsylvania | 4.50 | 3.50 | 8.00 Bangor, Pennsylvania | 4.50 | 3.50 | 8.00 Lehigh, Pennsylvania | 4.00 | 3.50 | 7.50 Buckingham, Virginia | 3.75 | 4.00 | 7.75 _Red Slate_ | | | Vermont | 12.00 | 4.25 | 16.25 _Green Slate_ | | | Vermont | 5.50 | 4.25 | 9.75 _Purple Slate_ | | | Vermont | 5.00 | 4.25 | 9.25 _Mottled Slate_ | | | Vermont (Purple and Green) | 4.00 | 4.25 | 8.25 ==================================+========+=========+============

=59. Sheet-Metal Roofs.=—In estimating sheet-metal roofs, the hips and valleys are measured extra their entire length by 1 foot in width, to compensate for increased labor and waste of material in cutting and laying. Gutters and conductor pipes, or leaders, are measured by the linear foot, 1 foot extra being added for each angle. All flashings and crestings are measured by the linear foot. No deductions are made for openings (chimneys, skylights, ventilators, or dormer-windows) if they are less than 50 square feet in area; if between 50 and 100 square feet, one-half the area is deducted; if over 100 square feet, the whole opening is deducted. An extra charge is made for labor and waste of material to flash around openings.

=60.= There are two regular sizes of roofing plates, namely, 20 in. × 28 in. and 14 in. × 20 in. The larger size is generally used on common work, owing to the fact that it requires fewer seams on the roof and consequently cheapens the cost of laying. A third size, namely, 10 in. × 20 in., is also supplied, and is used generally for gutters and leader pipes. Sheets 10 in. X 14 in. are sometimes used for laying roofs, as they can be cleated better than the larger sizes. Such small sheets, however, cost more to lay.

Two thicknesses of roofing plates are commonly recognized. One is the IC, or No. 29 gauge, and weighs 8 ounces to the square foot; the other is the IX, or No. 27 gauge, and weighs 10 ounces to the square foot. Sometimes, a still heavier plate is called for, and it is therefore kept in stock by the best manufacturers. This plate is known as IXX, or No. 26 gauge, and is used for especially heavy work.

Formerly, the standard net weight per box of IC, 14" × 20" roofing tin was 112 pounds, or 1 pound per sheet, making 112 sheets to the box; but now this weight is reduced to 108 pounds. The old standard for IX plates was 140 pounds, but very few brands now weigh more than 135 pounds per box. The most reliable manufacturers guarantee the weights for the different boxes of tin, and if the material does not come up to the guaranteed weight, it can be returned. The best sheets in the market today are stamped with the mark of the brand and the designation IC or IX of the thickness.

=61.= Using standing joints, a 14" × 20" sheet of roofing tin will cover about 235 square inches of surface, or one box of such tin will cover about 182 square feet. With a flat, lock seam, a sheet will cover 255 square inches, allowing ⅜ inch all around for joints; or a box will lay 198 square feet. These figures make no allowance for waste.

Two good workmen can put on from 250 to 300 square feet of tin roofing per day of 8 hours; this also includes painting the outside of the tin. Tin roofing will cost from 8 to 10 cents per square foot, depending on the quality of material and workmanship.

=62. Tile Roofs.=—Since =tile roofs= are constructed of so many styles of tile, no general rules of measurement can be given. Every piece of work must be estimated according to the particular kind of tile used and the number of sizes and patterns. Information on all these points is to be found in the catalogs of tile manufacturers.

TABLE XIII

APPROXIMATE COST OF ROOF TILING, PER SQUARE =======================================+=========+=========+========== | | Cost of |Total Cost Classification | | Laying |Exclusive | Cost |Including| of | of Tile | Ashphalt|Builder’s |Delivered| Felt | Profit ---------------------------------------+---------+---------+---------- Shingle tile (rectangular), 6" × 12" | $13.00 | $ 7.50 | $20.50 Shingle tile (rectangular), 8" × 12" | 14.00 | 6.50 | 20.50 Shingle tile (geometric shapes) | 12.00 | 7.00 | 19.00 Conosera (interlocking), 8" × 12" | 14.00 | 5.50 | 19.50 Conosera (interlocking), 10" × 15" | 12.00 | 5.00 | 17.00 Conosera, combination 8" × 12" | | | and 2" × 12" | 16.50 | 8.00 | 24.50 French A (interlocking), size 10" × 15"| 12.00 | 5.00 | 17.00 Spanish, 8" × 12" | 13.00 | 6.50 | 19.50 Old Spanish, semicircular, channels | | | laid alternately, concave and convex | 22.50 | 10.00 | 32.50 Roman, pan and semicircular roll, | | | laid 7½ in. center to center of rolls| 17.00 | 8.00 | 25.00 Greek, pan and semihexagonal cap, | | | laid 7½ in. center to center of caps | 17.00 | 8.00 | 25.00 Promenade for flat roofs, laid on 5 | | | layers of asphalt felt in asphalt | | | pitch | 7.00 | 13.00 | 20.00 =======================================+=========+=========+==========

In Table XIII is given a list of the prevailing styles of roof tiling, the cost of tiling, labor, etc. per square, pertaining to each variety. The prices in the table are based on the natural red color of the clay when burnt; extra prices are asked for glazed-surface finish which can be obtained in different colors. The prices in the table are based on quantities of not less than 30 squares, as less than a minimum carload means increased freight rates. The prices given cover railroad delivery to points in the Eastern and Middle States. Labor, etc. being based on current prices.

The above prices are figured on the tile being laid on wooden sheathing; if laid on book tile or cement add 20 per cent.

If copper nails are used, care must be taken in figuring the number of nails, as well as their length and gauge, for the special forms of tile specified. Fluctuating values of copper make this an item of much importance.

Ridges, hip rolls, barge tile, and finials are charged as extras and due allowance must be made for cutting at valleys and hips.

=63. Gravel Roofs.=—In =gravel roofing=, the cost per square depends on the number of thicknesses of tarred felt and the quantity of pitch used per square. A value of 4 cents per square foot for four thicknesses may be considered an average.

ROOF MENSURATION

=64.= While a knowledge of how to apply the ordinary principles of mensuration is all that is necessary to calculate any roof area, yet the modern house, with its numerous gables and irregular surfaces, introduces complications that render some further explanation of roof measurement desirable. The most common error made in figuring roofs—and one that should be carefully guarded against—is that of using the apparent length of slopes, as shown by the plan or side elevations, instead of the true length, as obtained from the end elevations.

[Illustration: FIG. 6]

=65.= The area of a plain gable roof, as shown in end and side elevations in Fig. 6, is found by multiplying the length _g j_ by the slope length _b d_, and further multiplying by 2, for both sides. The area of each gable is found by multiplying the width of the gable _a d_ by the altitude _c b_, and dividing by 2.

[Illustration: FIG. 7]

[Illustration: FIG. 8]

[Illustration: FIG. 9]

=66.= In Fig. 7 is shown the plan and elevation of a hip roof, having a deck _z_. The pitch of the roof being the same on each side, the line _c d_ shows the true length of the common rafter _l m_.

In Fig. 8 is shown the method of developing the true lengths of the hips and the true size of one side of the roof. Let _a b c d_ represent the same lines as the corresponding ones in Fig. 7. From the line _a d_, Fig. 8, through _b_ and _c_, draw perpendiculars, as _g h_ and _e f_; lay off from _g_ and _e_ on these lines, the length of the common rafter _c d_, Fig. 7, and draw the lines _a h_ and _d f_, Fig. 8; then the figure _a h f d_ will represent the true shape and size of the side of the roof shown in the elevation in Fig. 7. The area of the triangle _d e f_ is equal to the area of the triangle _a g h_ or a similar triangle _a i h_. Hence, the portion of the roof _a h f d_ is equal in area to the rectangle _a i f e_, the length of which is half the sum of the eave and deck lengths, while its breadth is the length of a common rafter.

=67.= A method of obtaining the lengths of valley rafters, applicable also to hip rafters, is shown in Fig. 9, which is the plan of a hip-and-gable roof. To ascertain the length of the valley rafter _a b_, draw the line _a c_ perpendicular to _a b_ and equal in length to the altitude of the gable; then draw the line _c b_, which will represent the true length of the valley rafter _a b_.

=68.= As an example of roof mensuration, the number of square feet of surface on the roof shown in Fig. 10 will be calculated.

[Illustration: FIG. 10]

The area of the triangular portion _a c b_ is equal to the slope length of _d c_ (found by laying off _c′ c_ equal to the height of the ridge above the eaves and drawing _c′ d_) multiplied by the length of the eaves line _a b_ and divided by 2. Multiplying the dimensions 13.5 feet and 23 feet, respectively, and dividing by 2, the area is found to be 155.3 square feet.

The area of the trapezoid _g f i h_ is half the sum of _f i_ and _g h_ (shown in their true length on the plan) multiplied by the true length of _h i_. The latter is found by marking the height of the gable _i i′_ on the ridge line, and drawing the line _i′ h_, which measures 10.6 feet. Performing these operations, there results

5 + 14 ------ × 10.6 = 100.7 square feet 2

for each side, or 201.4 square feet for both. As each of the side gables is the same size, the area of the two roofs is 201.4 × 2 = 402.8 square feet.

The area of the polygon _q p n k_ is equal to the triangle _q p w_ minus the triangle _k n w_, the area covered by the intersecting gable roof. The former is equal to the triangle _a c b_, the area of which is 155.3 square feet. The area of _k n w_ is equal to half of _n w_, or 6.5 feet, multiplied by the true length of _k s_ or the altitude of the triangle; the latter is obtained by laying off _k k′_ equal to the height of the gable, 5.5 feet, at right angles to _k s_, and drawing _s k′_, which is the required altitude and which measures almost 7.4 feet. Then _k n w_ = 6.5 × 7.4 = 48.1 square feet; whence _q p n k_ equals 155.3 - 48.1 = 107.2 square feet.

The area of _a p q c_ is

_a p_ + _q c_ ------------- 2

multiplied by the true slope length of _t v_, or _t v′_, which measures 15.2 feet. Substituting dimensions, the area is found to be

6 + 24 ------ × 15.2 = 228 square feet. 2

From this deduct the area of _y z u_, which is the portion covered by the intersecting gable roof. The true length of _t u_ along the slope is _t u′_, measuring 12 feet; hence, the area of _y z u_ is

14 × 12 ------- = 84 square feet. 2

The net area of _a p q c_ is therefore 228 - 84 = 144 square feet; _b c q w_ being equal to _a p q c_, its area is the same, making the area of both sides 288 square feet.

The area of _k n m l_ is

_m n_ + _l k_ -------------- × _m l′_, 2

the slope length of _m l_. Substituting dimensions, the area is

11 + 16 ------- × 8.5 = 114.8 square feet. 2

As _k l x w_ is equal to _k n m l_, the area of both is 229.6 square feet.

Adding the partial areas thus obtained, the sum is 155.3 + 402.8 + 107.2 + 288 + 229.6 = 1,182.9 square feet, or approximately 11.9 squares.

PLASTERING

=69. Plastering= on plain surfaces, such as walls and ceilings, is always measured by the square yard. In determining the cost of plastering walls and ceilings, measure the surface actually plastered, making no deduction for grounds or for openings less than 7 superficial yards. For surfaces of domes or groined ceilings, beams, coves, paneling, etc., a unit price is fixed by the linear or the superficial foot, according to the character and disposition of the work. Round corners and arrises should be measured by the linear foot.

On interior work, increase the price 5 per cent. for each 12 feet above the floor after the first. For outside work, add 1 per cent. for each foot above the lower 20 feet. All repairing and patching should be done at agreed prices.

=70. Stucco Work.=—In estimating =stucco work=, cornices composed of plain members and panel work are measured by the square foot. Enriched cornices with carved moldings are measured by the linear foot. When moldings are less than 12 inches in circumference, measurement is taken by the linear foot; when over 12 inches, superficial measurement is used. For internal angles or miters, add 1 foot to the length of cornice, and for exterior angles add 2 feet to the length. Sections of cornice less than 12 inches measure as 12 inches. Add one-half for raking cornices.

For cornices or moldings abutted against a wall or plain surface, add 1 foot to the length of cornice; if against the soffit of stairs or other inclined or covered surface, add 2 feet to the length of cornice. Octagonal, hexagonal, and similar cornices, less than 10 feet in single stretches, take one and one-half times the length.

For circular or elliptical work, charge double price; for domes and groins, three prices. Enrichments of all kinds should be estimated at an agreed price.

=71. Cost of Plastering.=—The following analysis of the cost of plastering for 100 square yards, for both three-coat and two-coat work, will be of assistance in making estimates. These costs are exclusive of the lathing, which will be taken up later.

COST OF 100 SQUARE YARDS OF THREE-COAT PLASTERING

_Scratch Coat_ 6 bushels of lime, at 25 cents per bushel $ 1.50 9 pounds of hair, at 4 cents per pound .36 ¾ cubic yard of sand, at $1.50 per cubic yard 1.13 5 hours, plasterer’s time, at 50 cents per hour 2.50 5 hours, laborer’s time, at 25 cents per hour 1.25 ------- Total $ 6.74

_Brown Coat_ 6 bushels of lime, at 25 cents per bushel $ 1.50 3 pounds of hair, at 4 cents per pound .12 1 cubic yard of sand, at $1.50 per cubic yard 1.50 13 hours, plasterer’s time, at 50 cents per hour 6.50 6½ hours, laborer’s time, at 25 cents per hour 1.63 ------ Total $11.25

_Finishing Coat_ 3½ bushels of finishing lime, at 35 cents per bushel $ 1.23 ½ barrel of plaster of Paris, at $1.75 per barrel .88 ⅜ bushel of white sand, at 27 cents per bushel .10 18 hours, plasterer’s time, at 50 cents per hour 9.00 4½ hours, laborer’s time, at 25 cents per hour 1.13 ------ Total $12.34

The total cost of 100 square yards of three-coat plaster, then, is $30.33, or about 31 cents per yard.

COST OF 100 SQUARE YARDS OF TWO-COAT PLASTERING

_Brown Coat_ 8 bushels of lime, at 25 cents per bushel $ 2.00 16 pounds of hair, at 4 cents per pound .64 1¼ cubic yards of sand, at $1.50 per cubic yard 1.88 8 hours, plasterer’s time, at 50 cents per hour 4.00 8 hours, laborer’s time, at 25 cents per hour 2.00 ------ Total $10.52

_Finishing Coat_ Same as given for three-coat work $12.34

The total cost of 100 square yards of two-coat plaster is therefore $22.86, or about 23 cents per square yard.

LATHING

=72. Lathing= is measured by the superficial, or square, yard, no openings under 7 superficial yards being deducted.

Plastering laths are about 1¾ inches wide, ¼ inch thick, and usually 4 feet long, the studding being generally placed 12 or 16 inches on centers, so that the ends of the laths may be nailed to them. The laths are usually set from ¼ to ⅜ inch apart, requiring about 1½, 1⁷/₁₆, or 1⅜ four-foot laths, respectively, to cover 1 square foot.

For a fair grade of work, a man will lay on an average about 15 bundles, or 1,500 laths, per day. The price usually paid for laying laths is 25 cents a bundle.

In the following analysis is given the cost of lathing 100 square yards of surface:

COST OF LATHING 100 SQUARE YARDS

14⁴/₁₀ bundles of laths, at 55 cents per bundle $ 7.92 9 pounds of threepenny nails, at $3.65 per hundred pounds .33 Putting on 14⁴/₁₀ bundles, at 25 cents per bundle 3.60 ------ Total $11.85

The total cost of lathing 100 square yards is therefore $11.85, or about 12 cents per square yard.

JOINERY

=73. Joinery= includes all the interior and exterior finish put in place after the framing and covering are completed; as, for example, door and window frames, doors, baseboards, paneling, wainscoting, stairs, etc. Most of these materials are worked at the mill and are brought to the building ready to set in place.

=74. Frames.=—In taking off =door= and =window frames=, describe and state sizes. Measure architraves by the running foot, giving width and thickness, whether molded or plain, and state the number of plinth and corner blocks.

=75. Sash.=—For =sash=, state dimensions (giving the width first); thickness of the material, molded or plain; style of check-rail and sill finish; thickness of sash bar; whether plain, single or double-hung; and sizes (giving dimensions in inches) and number of lights. Use standard sizes as much as possible.

=76. Doors.=—In taking off =doors=, describe and state the sizes and thicknesses, whether the framing is stuck-molded, raised-molded, or plain; and number of panels, whether plain or raised. Use stock sizes wherever possible and suitable. For special work, where doors are to be veneered, state thickness of veneer, how cores are to be built, and the kind of wood to be used.

=77. Blinds.=—Describe size and thickness of =blinds=; whether paneled or slatted (fixed or movable), and whether molded or plain.

=78. Baseboard and Beam Casings.=—Measure the =baseboard= and =beam casings= by the running foot, stating width and thickness of stuff, and whether molded or plain. When a shoe is used for the base, so state; also, if a surbase is required, give particulars.

=79. Wainscoting.=—Measure =wainscoting= by the superficial foot. State kind of finish, whether paneled or plain, and style of molding and panels. Wainscoting cap and base, measure by the running foot.

=80. Stairways.=—Often =stairways= are taken by the contractor at so much per step, complete according to specifications. In measuring stairways, take off the amount of rough material in carriage timbers, and the planed lumber in treads, etc. Measure balustrades by the linear foot. Give description of newels. Measure spandrel and stairway paneling the same as wainscoting.

=81. Inside Fixtures.=—_Kitchen dressers_ may be taken at a fixed price complete; or at a fixed rate per square foot; or as dressed lumber, drawers and doors being taken separately. _Wardrobes_, _bookcases_, _mantels_, and _china closets_ should be treated separately, and a fixed price stated.

=82. Porches, Etc.=—_Porches_, _exterior balustrades_, _balconies_, _porte cochèrs_, etc. may be taken at a price per linear foot, or the actual quantity of material may be measured.

JOINERY DATA AND EXAMPLES OF ESTIMATING COSTS

=83. Molding.=—Molded work that goes through the mill is usually charged for by the square inch of section per foot in length. Thus, if the price is 1 cent per square inch of section per foot in length, a molding ⅞ in. × 4¾ in. and 12 feet long will cost 60 cents, because the section in the rough is 1 in. × 5 in., or 5 square inches. Therefore, 1 foot of this molding will cost 5 cents, and 12 feet will cost 60 cents. This method of charging for molding, however, is not altogether satisfactory, because it requires as much time to put a narrow piece of molding through the molding machine as it does a wide piece, and a wide piece, since it will have a larger sectional area, will bring a higher price.

A molding machine operates at different speeds, being run at a slow speed when cutting hard woods and at a high speed when cutting soft woods. A machine will turn out from 900 to 4,800 linear feet of molding of any width per hour, the 900 feet representing the amount of very hard wood run through the machine, and the 4,800 feet the amount of soft wood run through when the machine is speeded up to its full capacity. The average output of a machine, however, is about 3,000 feet per hour.

The cost of the machine with a man to operate it may be considered as 70 cents an hour on an average, the man getting 30 cents per hour and the machine being charged for at the rate of 40 cents per hour. Therefore, according to these figures, the cost of machining per linear foot is only ⁷⁰₃3₀₀₀, or .023 of 1 cent. It will thus be seen that the actual cost of putting molding through the machine, especially in large quantities, does not amount to much.

For this reason, especially in the eastern cities, it is cheaper to buy molding direct from the lumber mill than to buy the rough material and then run it through the mill at its destination. In nearly every instance the saving effected in putting the rough material through the machine at its destination is more than counterbalanced by the extra cost of freight rates due to the extra weight. For the same reason, in the eastern market today planed boards are really as cheap as rough ones, because the planed boards are lighter and thus cost less freight.

The cost of molding is governed almost entirely by the cost of the raw material, and is always reckoned from a base price of 1 cent per square inch of section 1 foot long. On this price a discount is given, depending on the kind of wood and the finish desired. At present an average discount for soft woods, such as white pine, spruce, cypress, etc., is about 35 per cent. Thus, the actual cost of pine molding 1 foot long and 1 square inch in cross-section is

35 65 1 - ---- = ---- of 1 cent. 100 100

No discount is given on hard woods in many of the large eastern cities at present—oak, birch, and the like being figured net. For walnut, mahogany, and other high-priced woods, a special price is set, depending on the market and the local prices.

=84. Cost of Window Frames and Windows.=—The following is approximately the cost of a window frame with two 28" × 28" lights, where all mill work is priced at ₆₅/₁₀₀ cent per square inch per foot:

COST OF WINDOW FRAME

Jambs at head, ⁵/₄" × 5" × 16' $ .65 Sill, 2" × 5" × 4' 0" .26 Sub-sill, ⁵/₄" × 6" × 2' 9" .14 Blind stop, 1" × 2" × 16' 0" .21 Parting stop, ½" × 1" × 16' 0" .11 Outside casing, ⁵/₄" × 5" × 12' 0" .49 Head casing, ⁵/₄" × 7" × 4' 0" .23 Rabbeted cap, ⁵/₄" × 4" × 4' 0" .13 Molding under cap, 1" × 3½" × 4' 6" .11 Sill nosing, ⁵/₄" × 4" × 4' 0" .13 Inside casing, including apron, 1" × 5" × 20' 0" .65 Back band, ⁵/₄" × ⁵/₄" × 16' 0" .17 Inside stops, ½" × 2" × 14' 0" .10 Four sash pulleys, at 3 cents per pulley .12 Making frame, 1 hour, at 40 cents per hour .40 ----- Total $3.90

The cost of setting and casing such a window frame is about 70 cents. The total cost of the frame set in place is therefore $3.90 + .70 = $4.60.

The cost of the frame per square foot of light is therefore

$4.60 × 144 ----------- = 43 cents 2 × 28 × 28

=85.= The cost of an ordinary window with two 28" × 28" lights may be estimated as follows:

COST OF SASH IN PLACE Cost of two sash, ⁶/₄, double-hung, glazed with single-thick American glass $2.10 Sash weights, 30 pounds, at 2 cents per pound .60 Cord, 22½ feet, at 1 cent per foot .23 Two sash lifts, at 5 cents each .10 Sash lock .15 Setting and hanging sash .35 ----- Total $3.53

If double American instead of single American glass is used, the cost just given should be increased by $1.

If the sash is glazed with single American glass, the cost per square foot of light will be

$3.53 × 144 ----------- = 33 cents. 2 × 28 × 28

Therefore, the total cost of window and frame in place is 43 + 33 = 76 cents per square foot. If the sash is glazed with double American glass, the cost per square foot of light will be

$4.53 × 144 ----------- = 42 cents. 2 × 28 × 28

Therefore, in this case the total cost of window and frame will be 43 + 42 = 85 cents per square foot.

For curved sash in curved walls, the cost is about twice as much as that of straight work.

=86. Cost of Door Frames and Doors.=—The following estimate represents the cost of an ordinary door frame. All molded work is put in the estimate at 1 cent per square inch of section per foot of length less 35-per-cent. discount, which is the same thing as ⁶⁵/₁₀₀ cent per square inch of section per foot.

COST OF A 2' 8" × 6' 8" DOOR FRAME IN PLACE

17 linear feet of ⁵/₄" × 6" rabbeted jambs $ .83 36 linear feet of 1" × 5" casing 1.17 36 linear feet of 1" × 2" back band .47 Dadoing and smoothing jambs and casing, 1 hour, at 40 cents per hour .40 Nails .05 Setting up jambs and casing,, 3 hours at 40 cents per hour 1.20 ----- Total $4.12

The area of the door is 2 ft. 8 in. × 6 ft. 8 in. = 17.78 square feet. Therefore, the cost of the preceding door frame per square foot of door is $4.12 ÷ 17.78 = 23 cents.

=87.= The following estimate gives the cost of a door of moderate price. The size of this door is 2 ft. 8 in. × 6 ft. 8 in. × ⁶/₄ in. It has four panels, is made of No. 1 pine, and is finished with solid ogee molding.

COST OF DOOR IN PLACE Price of door $2.75 Setting door, putting on hinges and lock, 2 hours, at 40 cents per hour .80 1 pair of 4" × 4" japanned-steel butts .16 1 mortise lock, brass-face knobs and escutcheons .70 ----- Total $4.41

If the door is provided with stuck molding instead of solid molding, it will cost about 50 cents more.

The area of the door is 2 ft. 8 in. × 6 ft. 8 in. = 17.78 square feet. The cost per square foot is therefore $4.41 ÷ 17.78 = 25 cents. The total cost of door and frame per square foot of door is therefore 25 + 23 = 48 cents.

=88.= The door just described has no transom. A transom 2 ft. 8 in. × 16 in., complete, will cost about $1. The area of such a transom is 2 ft. 8 in. × 16 in. = 3⁵/₉ square feet. The cost per square foot is therefore $1 ÷ 3⁵/₉ = 28 cents.

The prices just given are for solid pine doors. Veneered hardwood doors are usually made to order. When the contractor bids on a house, the architect as a rule has not yet detailed the veneered doors; therefore, the contractor is more or less uncertain as to what will be required and usually puts in a price that he thinks will cover the cost. In the eastern part of the United States, for a veneered door, with ¼-inch veneers built of staved-up cores, a price of from 35 to 50 cents per square foot will be found adequate. This price does not of course include the frame.

=89.= There is now on the market a ready-made, veneered birch door known as the _Korelock door_. In using these doors, it is always cheaper to make the door frame of the correct size to take stock-size doors. The price of these doors is quite reasonable. For a 2' 8" × 6' 8" × ⁶/₄" door, with six cross-panels, the price is $2.80 for ⅛-inch veneer; if the door is ⁷/₄ instead of ⁶/₄ inch, the price is $3.25. This price of course includes no hardware or frame. A 2' 8" × 6' 8" × ⁶/₄" two-panel door costs $3.30, and if ⁷/₄ inch, it costs $3.75. A 2' 8" × 6' 8" × 1⅜", half-glass door, with plain glass, costs $5.55; with art or lace glass, the price is $6.20. This price includes the glass. If the door is 1¾ inches thick instead of 1⅜ inches, 65 cents should be added to the two prices just stated.

A fair workman can hang, trim, and put hardware, including mortise lock, on about four ordinary doors per day. For veneered doors, or those requiring extra care, not more than two can be put in place in a day by one man.

=90. Cost of Baseboards, Rails, and Moldings.=—The cost of material and fitting in place of baseboards may be estimated at 1³/₁₀ cents per square inch of section per linear foot. This price is for pine; if hardwood is used, the price will be 2 cents. The same rule also applies to chair rails, cap rails, and natural-finish picture moldings.

=91. Cost of Paneling and Wainscoting.=—Paneling may be estimated at 20 cents per square foot for ⅞-inch pine; if over ⅞ inch, add simply for extra material. If the paneling is of hardwood and veneered, add 50 per cent. to the price of pine.

Plain wainscoting may be estimated at 9 cents per square foot, the cap being figured separately by the linear foot.

=92. Cost of Stairs.=—The cost per step for an ordinary stairway, constructed according to the following specifications, is about $3.55. For a better class of work, about one-quarter should be added to this price. Length of steps, 3 feet; tread, Georgia pine; riser, white pine; open string, white pine; nosing and cove; dovetail balusters, square or turned; rail 2½ in. × 3 in.; 6-inch start newel, cherry; two 4-inch square angle newels, with trimmed caps and pendants; simple easements, furred underneath for plastering; treads and risers tongued together, housed into wall strings, wedged, glued, and blocked.

The material of such a stairway will cost about $1.84 per step. This rate includes landing fascia and balustrade to finish on upper floor. The labor on the same, mill work and setting in place, is about $1.71 per step. For example, for a stairs having 17 steps and landing balustrade (including return, about 14 feet), the entire cost will be 17 × $3.55 = $60.35, of which $31.28 will represent the cost of dressed lumber, including turned balusters and newels and worked rail, and $29.07 will represent the cost of labor in housing strings, cutting, mitering, and dovetailing steps, working easements, fitting and bolting rail, and erecting stairway in building.

=93. Cost of Verandas.=—For small dwellings, it has been found by experience that a veranda built according to the following specifications will cost about $3.75 per linear foot: Width, 5 feet; posts, turned, set 6 or 8 feet on centers; floor timbers, 2 in. × 6 in.; flooring, ⅞-inch white pine, sound grade; rafters, 2 in. × 4 in., dressed; purlins, 2 in. × 4 in., set 2 feet on centers; roof sheathing, ⅞-inch white pine; box frieze and angle mold; angle and face brackets; steps; no balustrade.

To include balustrade with 2-inch turned balusters, add about 60 cents per linear foot.

For a veranda built according to the following specifications, the cost will be about $6.75 per linear foot: Width, 8 feet; columns, 9-inch, turned; box pedestals; box cornice and gutter; level ceiling; roof timbers, 2 in. × 6 in.; roof covered with matched boards; tin, a good grade; floor timbers, 2 in. × 8 in.; floor, 1¼-inch white pine, second grade, with white-lead joints; no balustrade.

Including balustrade, with 2½-inch turned balusters, rail, and base to suit, add 80 cents per linear foot.

Where a portion of the veranda is segmental or semicircular, a close approximation to the cost will be had if the circumference of the circular part is measured, and a rate fixed at twice that for straight work of the same length. This applies to veranda framing, roofing, casing, and balustrades.

STRUCTURAL STEEL

=94.= The price of =structural steel= varies continually as the steel market fluctuates. The cost of erecting steel also varies continually and depends on the difficulties to be overcome. Heavy steel work costs less per pound than light roof trusses and domes, because less shop work is required in proportion to the weight. For average prices in the eastern part of the United States, heavy steel may be taken at 3³/₁₀ cents per pound. Roof trusses, due to extra framing, will cost about 3⁸/₁₀ cents per pound, and light, complicated dome work will cost 6½ cents per pound. These prices are for steel delivered and painted. To erect steel costs anywhere from ½ to 2 cents per pound, depending on local conditions.

HEATING AND VENTILATING SYSTEM

=95. Heating and ventilating work= should be estimated as indicated in the following paragraphs:

Estimate all pipes and fittings the same as for plumbing. Sum up all standard radiators, and the price per square foot of radiation. Figure special radiators separately.

Itemize all valves, air vents, hangers, etc.

Estimate on pipe coverings by linear foot.

Estimate sheet-metal, indirect-radiator casings in pounds.

Estimate sheet-metal flues and smoke pipes by the linear foot; but estimate elbows and dampers separately.

Estimate register boxes, registers, and borders separately.

Make separate items of expansion tanks, hot-water damper regulators, and furnace regulators.

Figure heaters, steam boilers, and furnaces from manufacturers’ catalogs.

In estimating on heating by furnace, the average cost of labor is about one-third that of materials. For steam and hot-water heating, the ratio is about one-fifth.

The cost of a hot-air installation is approximately 6 per cent. of the cost of the building; for steam heating, 8 per cent.; and for hot-water heating, 10 per cent.

PLUMBING AND GAS-FITTING

PLUMBING

=96.= An approximate figure for the cost of =plumbing= is 10 per cent. of the cost of the building. This figure is for good materials and labor, and of course is subject to considerable variation. The cost of labor alone will average about one-fourth the cost of the materials.

=97. Drainage System.=—In making estimates for the =drainage system=, measure all horizontal pipes from the plans and all vertical pipes from the sectional drawings.

Commence at the sewer outlet and measure the main-sewer line forwards into the building; then measure the horizontal branches.

Measure the vertical, soil, waste, and vent stacks to their terminations above the roof, and waste-pipe branches to the fixtures on the several floors.

Itemize the several pipes in the different kinds and classes.

Estimate all earthen pipe by the linear foot, allowing for Portland cement in the joints.

Estimate all cast-iron pipe by the linear foot, allowing for each joint ¾ pound of lead for every inch in diameter of the pipe.

Estimate wrought pipe by the linear foot, inclusive of couplings.

Estimate brass, copper, and lead pipe by the pound.

Estimate all traps, bends, branches, increasers, reducers, and other fittings separately, except such special brass fixtures, traps, and connections as are included in the cost of the fixtures. Do not figure lead bends that are smaller than 2 inches.

Estimate on brass ferrule connections at all points where lead pipe joins iron pipe.

Estimate on all solder joints (wiped), allowing 1 pound of solder for every inch inside diameter of the pipe.

=98. Water-Supply System.=—For water supplied from street mains, allow for permits, corporation tapping, and curb box.

Measure the service pipe from street main to cellar, and allow for a stop and waste cock inside the cellar wall.

Measure all horizontal distributing pipes from the plan views of the building and all vertical distributing pipes from the sectional drawings.

Measure all branches for the several fixtures on the different floors, to the lawn hydrants, etc.

Itemize the different kinds and classes of pipes.

Estimate lead, brass, and copper water pipes by the pound, and wrought water pipe by the linear foot.

Itemize all stop-cocks, pipe supports, straps, hangers, etc. separately.

Estimate all water-pipe fittings less than 1½ inches by the pound.

Figure on brass solder-nipple connections in all places where lead pipes join iron pipes.

Estimate on kitchen boiler, sediment cock, and range connections; also on faucets for all fixtures other than those which are included in the costs of the fixtures.

Estimate on garden hydrants and lawn sprinklers, and allow a stop and waste cock in cellar for each.

=99. Well Supply.=—For water supplied from a well, figure on double-action force pump in kitchen or laundry if the well is not deeper than 26 feet below the pump; for a deep well, estimate on a pumping engine or a windmill.

Measure lead tank linings in square feet, and estimate by the pound, allowing 1 pound of solder for every 2 feet of seams.

Allow 2 feet of lead pipe to connect iron pipes to house tank, and for stop-cocks close to tank.

Provide for telltale and overflow pipes for tank.

Estimate copper tanks in square feet and by the pound.

If there are iron, slate, glass, or cedar tanks, figure them separately.

=100. Fixtures.=—Estimate each =fixture= separately, and include traps, faucets, waste, vent, and water connections to walls or floors. When the sewer is long and has but little fall, figure on using a grease trap for the kitchen sink.

GAS-FITTING

=101. Cost.=—The cost of the =gas-fitting= may be approximately figured as about 3 per cent. of the cost of the building. The cost of labor alone varies from about one-fourth to one-seventh of the cost of materials. The better the grade of fixtures, the lower will be the ratio, provided there is no excessive ornamentation requiring much time to put in place, as the cost of the labor is about the same for cheap fixtures as for more costly ones.

=102.= Estimate piping the same as for plumbing.

Allow for meter, permits, tapping gas main, etc.

Figure each gas fixture separately set up in place. The owner usually makes a selection of fixtures from the manufacturer’s catalog. Allow for shields, fireguards, etc. in places where there is danger of fire.

Figure gas grates, gas stoves, gas heaters, etc. separately. Where the gas pressure is very high or unsteady, allow for a pressure regulator.

PAINTING AND PAPERING

PAINTING

=103. Painting= is measured by the superficial yard, girting every part of the work that is covered by paint, and allowing additions to the actual surface to compensate for the difficulty of covering deep quirks of moldings, for carved and enriched surfaces, etc. Ordinary door and window openings are usually measured solid, to compensate for the extra time taken in working around them, “cutting in” the window sash, etc. Porch and stair balustrades, iron railings, and work having numerous thin strips, are also counted solid, for a similar reason. Allowance is frequently made for the distance from the ground that the work is to be done, as in cornices, balconies, dormers, etc., and also for the difficulty of access.

Charges are usually made for each coat of paint put on, at a certain price per superficial yard and per coat.

Graining and marbling (imitations of wood and stone) and varnishing are rated at different prices from plain work.

Capitals and columns and other ornamental work that is difficult to measure should be enumerated, and a clear description of the amount of work on them should be given.

DATA ON PAINTING

=104. Quantities.=—One pound of pure lead-and-oil paint will cover from 2¾ to 3¼ square yards of wood for the first coat, and from 4½ to 6 square yards for each additional coat; on brickwork, it will cover about 1½ and 2 square yards, respectively. Colored paint will cover about one-third more surface than white paint.

Using prepared or ready-mixed paint, 1 gallon will cover from 250 to 300 square feet of wooden surface, two coats; for covering metallic surfaces, 1 gallon will be sufficient for from 300 to 400 square feet, one coat. The weight per gallon of pure mixed paints varies considerably, but, on an average, may be taken at about 16 pounds.

Prepared shingle stains will cover about 200 square feet of surface per gallon if applied with a brush; or, this quantity will be sufficient for dipping about 500 shingles. Rough-sawed shingles will require about 50 per cent. more stain than smooth ones.

One pound of cold-water paint, for the first coat, will cover from 50 to 75 square feet of wood, according to the surface condition, and about 40 square feet of brick and stone.

One gallon of liquid pigment filler, hard-oil finish, or varnish will generally cover from 350 to 450 square feet of surface for the first coat, according to the nature of the wood and the finish, and from 450 to 550 square feet for the second and subsequent coats. One pound of paste wooden filler will cover about 40 square feet.

One gallon of varnish weighs from 8 to 9 pounds; turpentine, about 7 pounds; and boiled or raw linseed oil, about 7¾ pounds.

For puttying, about 5 pounds of putty will be sufficient for 100 square yards of interior and exterior work.

For sizing, about ½ pound of glue is used to 1 gallon of water.

For mixing paints, the figures given in Table XIV represent the average proportions of materials required for each 100 pounds of lead.

TABLE XIV

QUANTITIES OF MATERIALS ========+======+=========+===========+========== Coat | Lead | Raw Oil |Japan Drier|Turpentine |Pounds| Gallons | Gallon | Gallons --------+------+---------+-----------+---------- Priming | 100 | 7 | ½ | -- Second | 100 | 4 | -- | 2 Third | 100 | 6½-7 | -- | ½ ========+======+=========+===========+==========

The drier is omitted in the second and succeeding coats, unless the work is to be dried very rapidly, as it is considered to be injurious to the durability of the paint.

On outside work, boiled oil is generally used in about the proportion of 1 gallon to 2 gallons of raw oil.

=105. Care in Painting.=—In painting woodwork, putty should not be used until after the first coat of paint or varnish has been applied. There are two reasons for this. In the first place, if putty is used on dry wood, the wood is liable to absorb the oil from the putty and leave it in a dry and crumbly condition. Then, also, the oil from the putty soaking into the wood will stain the wood dark, and this stain may be seen through varnish. For this latter reason, putty should be put in cracks and holes with a putty knife and not with the fingers, as otherwise the oil from the putty will get over the fingers and thus be transferred to the woodwork, where it will show as a dark stain if the wood is varnished.

Due care should also be taken in painting woodwork that has knots in it, as otherwise the turpentine in the knot will be sure to discolor the paint in course of time. To avoid this, the knots should be coated, or _killed_, with a coat of shellac before the first coat of paint is applied. The shellac prevents the turpentine in the knot from soaking through and discoloring the paint.

=106. Cost of Painting.=—The cost of applying paint on general interior and exterior work will average about twice the cost of the materials, while for very plain work, done in one color, the cost may be taken at about 1½ times that of the materials. For stippling, the cost will be about the same as for two coats of paint. For varnishing, the cost of labor will be about 1½ times the price of the varnish.

The following figures represent fair average prices, for various classes of work, and have been adopted by the Builders’ Exchange of a large eastern city:

COST PER SQUARE YARD INTERIOR WORK CENTS

1 coat of paint, including shellacking knots 10 2 coats of paint, including puttying 20 3 coats of paint, including puttying 25 to 30 1 coat of shellac 15 Walls, 1 coat of size, 2 coats of paint 20 Walls, 1 coat of size, 3 coats of paint, stippled 30

_Hardwood Finish_ 1 coat of paste filler, 1 coat of varnish 25 1 coat of paste filler, 2 coats of varnish 40 1 coat of paste filler, 3 coats of varnish 50 1 coat of paste filler, 3 coats of varnish, rubbed down to dull finish 60 to 75

_Finish on Soft Woods_ 1 coat of liquid filler, 1 coat of varnish 20 1 coat of liquid filler, 2 coats of varnish 30 1 coat of liquid filler, 3 coats of varnish, rubbed 50 Floors: filling, shellacking, varnishing, or waxing, 2 coats (or 4 coats in all) 40

_Tinting Walls (Cold-Water Paint)_ Tinting, 50 yards or less, including sizing 12 Tinting, 50 yards or more, including sizing 10

=107.= In =staining= hardwoods with open grain, such as oak, chestnut, ash, etc., it is customary, when a varnished surface is required, to stain the paste filler with oil colors so as to secure the desired tint and then finish with three or four coats of varnish. The staining adds about 5 cents per square yard to the cost of varnishing.

When it is desired to color the silver grain, or medullary rays, revealed in quarter-sawed material, the usual plan is first to stain the material with an oil or an aniline stain that permanently affects only the silver grain. Afterwards, the paste filler colored to the desired tint is applied, and this, on entering and closing the open grain, buries the first stain, but does not cover that over the medullary rays. This, as in the previous method of staining, adds about 5 cents a square yard to the cost of varnishing.

Another method of treating oak, chestnut, and ash is to stain the wood to the desired shade with an oil stain of the proper tint. This stain is applied with cheesecloth to an even surface, and, after puttying, one coat of flat varnish is applied. This process costs about 25 cents per square yard.

For silver-gray effects, the addition of aluminum bronze to the oil stain will give a pleasing effect. This costs about 28 cents per square yard.

When it is desired to have the open grain show a white effect, the usual method is to use a paste filler with zinc white added and then a coat of flat varnish. This costs about 30 cents per square yard.

Oak, chestnut, and ash maybe colored by fuming (to give the effect of age) with the vapors of ammonia released in a closed box. This effect is also produced by several patented processes. It costs about 30 cents per square yard.

EXTERIOR PAINTING COST PER SQUARE YARD _Woodwork_ CENTS 1 coat of paint 10 2 coats of paint, including puttying 18 3 coats of paint, including puttying 25 to 30

_Common and Pressed Brickwork_ 1 coat of paint 15 2 coats of paint 25 3 coats of paint 35 Penciling and lining joints on painted brickwork 05 Penciling joints on pressed, unpainted brickwork 10

_Sanding_ 2 coats of paint, 1 coat of sand 28 3 coats of paint, 1 coat of sand 35

_Miscellaneous_ COST Dipping shingles, per 1,000 $3.00 Additional coat, per 1,000 shingles .50 Brush-coating shingles, per square yard .15 Blinds, per square foot, 1 coat, painted on both sides .04 Additional coat for blinds, per square foot .04 Iron fence, per square foot, 1 coat, painted on both sides .04 Tin roof, per square yard, 1 coat .05 Additional coat for tin roof, per square yard .04

=NOTE.=—For painting sand-lime bricks, double the prices given for common and pressed brickwork.

PAPERING

=108. Papering= is usually figured per roll, put on the wall. The paper is generally 18 inches wide, and is in 8-yard rolls; double rolls are 16 yards. On account of waste in matching, etc., it is difficult to estimate very closely the number of rolls required, but an approximate result may be obtained as follows: Divide the perimeter of the room by 1½ (the width of paper in feet); the result will be the number of strips. Find the number of strips that can be cut from a roll, and divide the first result by the second; the quotient will be the number of rolls required. No openings less than 20 square feet in area should be deducted, in order to compensate for cutting and fitting at such places. About 15 per cent. should be added to the area to allow for waste. The border, whether wide or narrow, is generally figured as one roll of paper.

The cost of paper is extremely variable, ranging from 15 cents to $6 per roll; the average cost is probably 25 to 50 cents per roll, for ordinary houses. Paper hanging costs from 10 cents to $1 per roll, according to quality, with strips butted.

GLAZING

=109.= =Glazing= was formerly included in the painter’s contract, but as it is now customary and more convenient to oil or paint and glaze the sash at the mill when they are made, the glazing is included in the joinery specifications, and is not considered as a separate subdivision of estimating work.

In measuring glass, take the dimensions between rabbets each way when the panes are rectangular; if irregular or circular in form, take the extreme dimensions, and consider the panes rectangular. It costs about 1½ cents per square foot of light to glaze a window. This price includes the cost of putty.

Polished plate glass is used extensively for store-front windows and also for glazing window sash in fine work. There are three qualities: French plate, and two grades of American plate, which may be obtained in various sizes up to 8 feet wide and 14 feet long. The cost of plate glass is estimated by the aid of a price list that gives the cost of the various sizes. This list is furnished by dealers and remains the same from year to year; it is known as the _standard list_. The fluctuations are provided for by means of a discount, which is the same for all sizes of glass.

TABLE XV

PANES OF WINDOW GLASS PER BOX ========+======+=========+======+=========+======+=========+===== |Panes | |Panes | |Panes | |Panes Size | in | Size | in | Size | in | Size | in Inches | Box | Inches | Box | Inches | Box | Inches | Box --------+------+---------+------+---------+------+---------+----- 6 × 8 | 150 | 16 × 22 | 21 | 22 × 28 | 12 | 26 × 58 | 5 7 × 9 | 115 | 16 × 24 | 15 | 22 × 30 | 11 | 28 × 28 | 9 8 × 10 | 90 | 16 × 34 | 13 | 22 × 32 | 10 | 28 × 30 | 9 8 × 12 | 75 | 16 × 38 | 12 | 22 × 34 | 10 | 28 × 42 | 6 9 × 11 | 73 | 16 × 44 | 10 | 22 × 36 | 9 | 28 × 52 | 5 9 × 12 | 67 | 18 × 20 | 20 | 22 × 38 | 9 | 30 × 30 | 8 9 × 13 | 62 | 18 × 22 | 18 | 22 × 48 | 7 | 30 × 40 | 6 10 × 12 | 60 | 18 × 24 | 17 | 22 × 52 | 6 | 30 × 50 | 5 10 × 14 | 52 | 18 × 26 | 16 | 24 × 24 | 12 | 30 × 54 | 4 10 × 16 | 45 | 18 × 32 | 13 | 24 × 26 | 12 | 32 × 32 | 7 10 × 18 | 40 | 18 × 36 | 11 | 24 × 28 | 11 | 32 × 36 | 6 12 × 14 | 43 | 18 × 42 | 10 | 24 × 30 | 10 | 32 × 48 | 5 12 × 16 | 38 | 18 × 52 | 8 | 24 × 32 | 10 | 32 × 52 | 4 12 × 18 | 34 | 20 × 20 | 18 | 24 × 34 | 9 | 32 × 58 | 4 12 × 20 | 30 | 20 × 22 | 16 | 24 × 36 | 9 | 32 × 62 | 4 12 × 22 | 27 | 20 × 24 | 15 | 24 × 38 | 8 | 34 × 34 | 6 12 × 24 | 25 | 20 × 26 | 14 | 24 × 40 | 8 | 34 × 36 | 6 14 × 16 | 32 | 20 × 28 | 13 | 24 × 42 | 7 | 34 × 46 | 5 14 × 18 | 29 | 20 × 30 | 12 | 24 × 44 | 7 | 34 × 50 | 4 14 × 20 | 26 | 20 × 34 | 11 | 24 × 46 | 7 | 34 × 56 | 4 14 × 22 | 24 | 20 × 36 | 10 | 24 × 52 | 6 | 36 × 36 | 6 14 × 24 | 22 | 20 × 38 | 10 | 24 × 60 | 5 | 36 × 44 | 5 14 × 26 | 20 | 20 × 40 | 9 | 26 × 26 | 11 | 36 × 48 | 4 14 × 36 | 14 | 20 × 52 | 7 | 26 × 28 | 10 | 36 × 54 | 4 14 × 40 | 13 | 22 × 22 | 15 | 26 × 32 | 9 | 36 × 58 | 3 16 × 18 | 25 | 22 × 24 | 14 | 26 × 44 | 6 | 36 × 64 | 3 16 × 20 | 23 | 22 × 26 | 13 | 26 × 52 | 5 | 40 × 60 | 3 ========+======+=========+======+=========+======+=========+=====

When stained or art glass is used, the specifications generally limit the cost, as the glass is made according to the architect’s designs or to approved designs submitted by manufacturers. The price depends more on the amount of lead or copper used than on the cost of the glass itself, and therefore no very close estimate can be made. The following figures are only approximate:

COST PER SQUARE FOOT Clear glass $1 to $3 Opalescent glass $1 to $3 Plate glass $2 to $4 Cathedral glass $3 to $5 Favrille glass About $8

Ordinary window, or sheet, glass is sold by the box, which contains, as nearly as possible, 50 square feet, whatever the size of the glass may be. There are two qualities of ordinary glass, known as _single_ and _double thick_, the former being about ¹/₁₆ inch thick, and the latter nearly ⅛ inch. Single-thick glass should never be used in panes over 24 in. × 24 in. in size. Table XV gives the number of panes of window glass in one box of 50 square feet.

ESTIMATING AND CALCULATING QUANTITIES

( PART 2 )

EXAMPLE IN ESTIMATING

=1.= Following the rules and suggestions already given in _Estimating and Calculating Quantities_,