Part 4

Some interesting experiments on concrete arches were made recently, during the construction of the new railway station at Erfurt. Some of the rooms were to be covered with concrete floors, carried on iron beams, while others, of smaller size, were intended to be spanned by arches extending from wall to wall. One of the latter, something over seven feet in width, was covered with concrete, flat on top, and forming on the underside a segmental arch, the thickness of the material at the crown of the arch being four inches, and about eleven inches at the springing. The concrete was made of "Germania" Portland cement, mixed dry with gravel, moistened as required, and well rammed on the centring; and skew-backs were cut in the brick walls at the springing line, extending two courses higher, so as to give room for the concrete to take a firm hold on the walls. Fourteen days after completion, this floor was loaded with bricks and sacks of cement to the amount of more than six hundred pounds per square foot, without suffering any injury, although, after the load was on, a workman hammered with a pick on the concrete, close to the loaded portion, so as to provoke the cracking of the arch if there had been any tendency to rupture. In the other cases, the concrete arches being turned between iron beams, the strength of the floor was limited by that of the beams, so the extreme load could not be put on; but the curious fact was established that a section of concrete flat on top, and forming a regular segmental arc beneath, was far stronger than one in which a portion of the under surface was parallel to the upper; showing, apparently, that the arched form, even with homogeneous concrete, causes the conversion of a large part of a vertical pressure into lateral thrust, reducing by so much the tendency of the load to break the concrete transversely. This observation is important theoretically as well as practically. It has been of late generally maintained that a concrete arch is not an arch at all, but a lintel, without thrust, and that the common form, flat above and arched beneath, is objectionable, as it gives least material at the centre, where a lintel is most strained. The Erfurt experiments directly contradict this view, and it remains for some students of architecture to render the profession a service by repeating them, and, at the same time, actually determining the thrust, for a given load, of arches of particular forms. Until this is done, the concrete construction, which is likely, we may hope, to become before many years the prevailing one in our cities, will be practised with difficulty and uncertainty, if not with danger. Incidentally, a trial was made of the effect of freezing on the concrete. The floor of a room arched in four bays, between iron beams, had just been finished when the weather became cold, and on the morning after its completion the thermometer stood at twenty above zero. The concrete had not been protected in any way, and the contractor was notified that it had been frozen, and must be removed. This was early in December, and it was about the first of April before the work of removal, preliminary to replacing the concrete with new material, was begun. Three bays had been wholly or partly removed when the hardness of the concrete under the workmen's tools attracted attention, and the arch remaining intact was tested with a load of three hundred pounds per square foot, which it bore perfectly.

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The question how far an architect can be held responsible in damages, in cases where the cost of work exceeds the estimates, is examined in a recent number of _La Semaine des Constructeurs_, and some considerations are mentioned which are new to us. According to Frémy-Ligneville, the most familiar authority on the subject, the architect incurs no responsibility whatever, either for his own estimates or those of other people, unless he intentionally and fraudulently misleads his client by a pretended estimate. In this case, as in that of any other fraud, he is liable for the results of his crime. Except under such circumstances, however, the architect's estimate of cost is simply an expression of opinion, the correctness of which he does not guarantee, any more than a lawyer guarantees the correctness of an opinion, although important interests may depend upon it. The owner can estimate the value of the architect's opinion, as of the lawyer's, by the professional reputation of the man who gives it, and, if he wishes to be more secure, he can go to another architect, as he would to another lawyer, for an independent estimate. Moreover, if the owner of the projected building is still anxious that the cost should be strictly limited to the sum estimated by the architects, he can have a contract drawn by which the builder shall be obliged to complete it for that sum, and can have his plans and specifications examined by competent authority, to see if they include everything necessary. This ought to make him reasonably sure what his house will cost him, provided he does not himself make changes in the plans or specifications. If he has omitted to take this precaution, and, as his building goes on, he finds that it is likely to exceed the estimate, he has another excellent opportunity to protect himself, by ordering immediately such changes in the plans and specifications for the work yet remaining to be done as may reduce the expense to the desired amount, and by doing so he generally suffers no damage, as, if he does not get all he expected to for his money, he gets all his money will pay for.

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With all these opportunities for revising and testing the correctness of an architect's estimate, the man who neglects to avail himself of any of them, and who allows the work on his house to go on, after it has become evident that it will cost more than the estimate, has, according to M. Frémy-Ligneville, no claim against any one on account of his disappointment. Of course, the architect should be as careful in his estimates as his experience allows him to be, and any conscientious man would try not to mislead a client, but both he and his client must remember that when the tenders of the builders themselves usually vary from fifty to a hundred per cent for the same piece of work, an architect's estimate cannot be anything more than an opinion. Moreover, the architect should not forget that, being an opinion, and not a guaranty, he is not only at liberty to modify it as much and as often as he sees fit, but is bound to do so, and to inform his client at once of the change, when fuller information, or alteration in the circumstances, shall show him that the original estimate is likely to be exceeded. If he does this frankly, although his client may be disappointed, he cannot reproach the architect with trying to deceive him, and there will probably still be time to make the changes necessary for reducing the expense to the desired point. In a case decided in Paris in July, 1855, a man was condemned to pay fifty-four thousand francs for repairs done on a house. He proved that his architect had estimated the expense at seven or eight thousand, but it was shown that the architect had subsequently informed him that it would be necessary to do more work than was at first contemplated, and that he had made inquiries about the matter, and had turned out his tenants so that the work might be done, and had paid the contractors more than the sum originally estimated; and the court thought he had no case at all against the architect.

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The great building firm of Peto Brothers, in England, having been awarded a contract for a large public building, have taken advantage of what, as they say, they consider a favorable opportunity to initiate a system of profit-sharing with their men, in accordance with a circular which is printed in the _Builder_. The system described by the circular is very simple. It is to apply for the present, only to the contract mentioned, but, if it works well, will be extended to future cases. Under the arrangement proposed one-quarter of the net profits of the contract are, when the building is done and the accounts settled, to be divided, as a bonus above their wages, among the men who have worked on it, in proportion to the wages they have earned. The conditions under which each man is entitled to his share are that he shall have worked long enough on the contract to have earned five pounds, at the regular rate of wages; that he shall not have neglected his duty, or misconducted himself, or wasted his time, or in other ways have acted so as to diminish the profits of the contract, or injure the reputation of the firm for good and honest work; and, that he shall not have engaged in any strike for shorter hours, or for wages above the schedule of wages which prevailed at the time the contract was made, and upon which the contract price was based. That the workmen may assure themselves of the fairness with which the division is carried out they are invited by the circular to send a representative to watch the making-up of the accounts by the auditor of the firm, and to sign the balance-sheet. In order to identify the claimants, every man must obtain a printed ticket from the time-keeper, on beginning his work, countersigned by the foreman, and noting the day and hour when his employment commenced, with his name, number and wages. This is to be again signed and countersigned when he leaves, and must be produced to secure a share in the dividend. Unpretending as it is, this bids fair to be one of the most interesting experiments in social science yet tried, and unless the trades-unions in England have forgotten their prowess, it will not be carried out without a struggle. Our readers will remember Mr. Lewis H. Williams's experiences in trying a similar plan with his carpenters in New York, and his final victory, but he had only one union to contend with, and that not a very compact one, while Messrs. Peto Brothers will have all the building trades about their ears at once, and the great question whether men shall be allowed to do only a fixed amount of work in a day, and that amount as small as possible, or whether they shall be allowed to work as they please, will be fairly brought before the parties for decision.

THE APARTMENT-HOUSE.

[Illustration: "THE SURE REVOLVING TEST OF TIME--PAST AND PRESENT" CARTOON FOR SGRAFFITO by HEYWOOD SUMNER.]

From _Building News_.

Most people are willing to admit that they cannot afford to pay over twice as much for a thing as it is worth; but few in this country are aware that they do this very thing when they build for themselves an independent city dwelling-house or pay a rent equivalent to or greater than the interest on this outlay.

In the old country the secret of obtaining luxury and economy combined in building has been learned, and rich and poor, fashionable and unfashionable alike live in "flats." In America, people have not yet learned this lesson, but cling to the old and barbarous custom of living _perpendicularly_ in isolated towers, with all the cares and worries that go with isolated management.

[Illustration: Figure 1.]

Nothing shows more clearly than this, how much man is a creature of habit. In his savage state, the nature of his existence necessitated the isolated hut. As civilization advanced, however, the necessity for, and enormous advantages of coöperation became evident, but habit perpetuated the isolated dwelling long after the reasons for its existence had disappeared, and it required centuries for civilized men to learn that coöperation is an element as essential to perfection in the arrangement of their habitations as it is in other things.

_A given accommodation may be obtained in the form of a "flat" for less than one-half the outlay required to obtain it in the form of an independent dwelling built on the same land._

The form of comparison herein presented has never, to my knowledge, been heretofore made, and the results are as surprising as they are important and interesting.

The estimates of cost have been made by several competent contractors on scale drawings and accurate specifications, are easily verified and hence may be accepted as reliable.

Figure 1 is one of the plans of our apartment-house which is to be built on the Back Bay, Boston.

Figure 2 shows the floor-plans of an independent house which might be built on the same land. Both figures are drawn to the same scale for convenience in comparing the dimensions. The independent-house (which I shall, in contradistinction to the "flat," designate as the "tower" to mark its prominent point of difference from the "flat" in form) contains a kitchen, pantry, furnace-room, fuel-cellar, laundry, dining-room, china-closet, parlor, eight bed-chambers provided with suitable closets, two bath-rooms, a trunk-room, a front staircase extending from the first floor to the attic, and a back staircase extending from the basement to the third floor. What will these accommodations cost in this form and what in the form of a "flat" in an apartment-house?

The apartment-house contains a public kitchen, steam-heating, ventilating and electric-lighting isolated plants, fuel-cellar, laundry, café, billiard-room, gentlemen's smoking-room, ladies' parlor, small public dining-rooms, and eighty suites, _averaging_ five rooms, a bath-room and closets in each, and with a trunk or storage-room in the basement for each suite; four elevators and four fireproof staircases of iron and marble enclosed in brick walls from basement to roof.

The suites are of different sizes to suit the proposed occupants, and will have from two to twelve or more rooms of varying dimensions as desired. They are partly "housekeeping" suites, _i. e._, having kitchens and dining-rooms; partly "hotel" suites, _i. e._, having neither kitchens nor dining-rooms, the occupants preferring to use the public café and dining-rooms; and partly "semi-housekeeping" suites, _i. e._, having dining-rooms and china-closets with dumb-waiters connecting them with the public-kitchen, but no independent kitchen. The "housekeeping" suites require one more bed-room than the others, to accommodate a private cook.

Assuming now at first in our comparison those conditions which are least favorable to the apartment-house, we will take one of the "housekeeping" suites, having precisely the same number and size of rooms as we find in our independent house or "tower" and compare costs.

The only difference in the accommodation in each case is that, in the "flat," the rooms are accessible to one another without the use of stairs, while in the "tower" six flights of stairs in all are used, constituting in the aggregate a ladder, as it were, of about a hundred steps; also in the fact that in the "tower" the owner has to manage his own heating, ventilating and hot-water supply apparatus, while in the "flat" this work is done for him; that in the "tower" wooden staircases and no elevators are used, while in the "flat" fireproof staircases enclosing elevators are provided; that in the "tower" the main partitions are often of wood while in the flat they are of brick a foot thick and each "flat" is separated from its neighbor by a brick wall a foot thick and all the floors are completely deadened against the transmission of sound; and finally that in the "tower" no external fire-escape is provided, while the "flat" has convenient external fire-escapes of iron. Otherwise the accommodations are in both cases precisely the same.

The total cost of this apartment-house, including the building-lot valued at, say, $5 a square foot, has been carefully estimated at $617,771.

This is the highest of two competitive estimates given by two responsible builders, and comprises general cooking-plant, electric-lighting, steam-heating and ventilating apparatus, iron staircases and fire-escapes, elevators, copper roofing, architect's commission, and, in short, everything required for occupancy and use except wall-paper.

The first floor contains 16,688 square feet of available room. (By "available" I mean room which is directly occupied by, and which must be separately provided for each owner. That is, it excludes staircases, furnace, laundry, etc., which might be used in common by many owners and therefore need not be duplicated for each, and which are only indirectly serviceable to each owner in contributing to the usefulness of those which are directly enjoyed.) The six floors above contain 23,288 square feet of available room each, making a total of 156,416 square feet. Adding 10,880 square feet for basement storage and trunk-room for the suites, and 2,000 square feet in the basement for barber's shop, apothecary, carriage and other offices along the street fronts, we have a total of 169,296 square feet of available room in the entire apartment-house. Dividing the total cost $617,771 by this figure we have $3.65 for the cost of each square foot of available room in the building.

Our "tower" measures twenty-five feet front on party lines, by seventy feet deep. Its available rooms comprise parlor, library, music-room, eight closeted-chambers, two bath-rooms, a trunk-room, a dining-room, and we may add a kitchen for those who still believe in having an independent cook.

The area of these rooms is as follows:

Parlor 374 sq. ft. Library 374 " Music-room 154 " Chamber No. 1 384 " Chamber No. 2 528 " Chamber No. 3 170 " Chamber No. 4 252 " Chamber No. 5 162 " Chamber No. 6 286 " Chamber No. 7 242 " Chamber No. 8 315 " 2 Bath-rooms 144 " Trunk-room 136 " Dining-room 408 " Kitchen 384 " China-closet 136 " Other closets 410 "

Making a total of 4,859 square feet of available room in the "tower." Its total cost on a twenty-five foot lot of the average depth on the Back Bay, _i. e._, 112 feet, the land being valued as before at $5 per square foot, would be at the lowest estimate $32,000 at the present prices, the wood finish being equally good with that in the "flat." If we figure, however, for the same style of lighting, heating, ventilating and fireproofing, and provide an elevator and outside fire-escape, the cost could not be put below $40,000.

The same amount of available space, _i. e._, 4,859 square feet in our "flat" would cost at $3.65 per square foot as above estimated, $17,735.

If now we consider that the management of a private kitchen and an Irish cook does not actually constitute the essence of a home in its broadest sense, but, that on the contrary, it really deprives a home of its greatest charm, namely, peace of mind and rest of body, the kitchen and the cook's bed-chamber may be omitted from our "flat" in view of the public kitchen. The area of our "flat" then becomes 4,475 square feet, which, at $3.65 per foot, brings the cost down to a little over $16,000.

Finally, if we omit the dining-room also, with its china-closet, our area becomes 3,931 square feet, and the cost only $14,350 for the "flat," against $40,000 for the "tower," the former being but little over a third of the latter.

So much for the saving in the case of a large family and large suite. For a small suite, such as would be required for a single person, or a small family of two or three persons, the saving at once mounts to a very much larger figure; so much so, indeed, as to render the use of the isolated house in such cases a most inordinate extravagance, except for the very rich. Thus a single person, or a family of two or three, could be very comfortably provided for with three or four rooms, and a bath-room in an apartment-house having a good café. Estimating the rooms to measure 18 x 22 feet, their area would be a little over 400 feet each, including closets, and their cost $1,460 apiece; or for smaller rooms of, say, 14 x 15 feet, or 224 square-feet surface, the cost would be but $818 apiece. An isolated dwelling, on the same land, of only eighteen feet frontage and fifty feet deep, would cost, including the lot at $5 a foot, not less than $18,000 or $8,000, without the land. Of course, in such an isolated dwelling, electric-lighting, steam-heating, fireproof stairs, and other luxuries of the "flat," would hardly be expected.

By the arrangement of our apartment-house, there are twenty-four corner-suites out of the eighty. These have direct sunlight on either one or both of their exposed fronts, and may be estimated as worth fifty per cent more than the rest. In other words, 3/10 of the whole available room space is worth fifty per cent more, and 7/10 correspondingly less than the average price of $3.65 per foot. Therefore, $3.65 x 1-1/2 = $5.47 = price of corner-suites per foot, 3/10 x the total area 169,296 square feet = 50,788 square feet x $5.47 = $277,810, which, deducted from $617,771, leaves $339,961 to represent the total cost of the remaining 7/10. The total area 169,296 x 7/10 = 118,507 square feet of available space in the inner-suites. Hence $339,961/118,507 = $2.86 as the price per square foot of the inner-suites, or all suites which are not corner-suites.

Now, as our estimates on the "tower" were made on the basis of its being an inner building in a block and not a corner-house, our estimates for the "flat" should be on a basis of $2.86, instead of $3.65, as taken. Therefore, our suite of 4,859 square feet would be but $13,896 if the "flat" were any other than a corner one, and if the public kitchen and café were used, it would be $11,242, or _but a little more than a quarter of that of the "tower!"_

The foregoing figures are easily explained, and their correctness verified by the following simple diagrams and considerations:

[Illustration: Figure 2.]

In Figure 2 the shaded parts of the plans represent the unavailable room which, under the apartment-house system, are rendered unnecessary, and they are practically wasted. Thus the eighty families, by uniting their eighty homes in one coöperative apartment, save 156 staircases consisting of seventy-six front and eighty back staircases, seventy-eight furnaces, seventy-nine laundries, etc., and nearly all the space they occupy, and the land, foundation and roof they represent.

[Illustration: Figure 3.]

This waste space may be graphically shown by the diagrams in Figure 3. The large black-and-white line represents the "tower," and the shorter the "flat." The black part of each line denotes unavailable, and the white part available room, the sum of the two denoting the total cubical contents of each dwelling. The white parts of the lines measure the same length in each case, because the amount of available room in "tower" and "flat" is assumed at the outset to be the same. Thus in the "tower," the front and back staircases and halls take up 22,000 cubic feet out of the total 106,000 cubic feet covered by the entire building. In the "flat" the proportional part of the halls and staircases for each suite is represented by a comparatively insignificant quantity as shown.