A MODERN APARTMENT HOUSE.
The monolithic reinforced concrete skeleton frame of a modern apartment house is shown at the right in Plate 16. From the footings to the roof, the entire framework is solid concrete re inforced with trussed bars. All the floors are of reinforced concrete and hollow-tile construc tion.
Besides the advantage of its economy of ma terials and time, this construction has other marked advantages for such a building as this. One of these is its insulating properties. Dry air is an excellent insulation, and the air con tained in the hollow spaces of the tile is a most excellent medium for preventing the passage of heat. For the same reason all the interior walls and partitions are built of hollow partition tile, thus insuring not only even temperature but freedom from noise as well, for the hollow tile is an insulation against sound as well as heat.
The floors of the bay windows are canti levered out over the wall beam at each floor. This is accomplished by inverting Kahn bars in the top of the projecting slab and allowing these bars to run well back into the regular floor-slab. The cantilevered slabs carry the wall and win dows of the bays from the second floor up. On the side of the building, two balconies are car ried in the same way from the fourth to the seventh floor. The cantilever is much greater, but tests have shown that the floors are equal to sustaining a greater load than any that will ever be put upon them.
The photograph shows the outside brickwork just being started in the front. At one side the outside wall is already up six stories. These walls are carried on the floor beams at each floor, while a single veneer course is carried all the way up on the outside in order to hide the skele ton entirely. In this way all the beauty of high class masonry is combined with the strength and stability of reinforced concrete.
The exterior finish is brick and stone, and presents very pleasing elevations. The interior is sound-proof, vermin-proof, and fireproof—a combination of highly desirable features.
Rapid and noiseless construction was abso lutely necessary. Speed was required because immediate use of the building was of great im portance. Reduction of noise was required as guests were being entertained in the older por tion of the hotel. For this reason structural steel was out of the question.
Reinforced concrete was used in all footings, columns, beams, floors, roof, and dome. The floors are of reinforced concrete and hollow-tile construction, varying in thickness from 4 to 12 inches. The cantilevered balconies, turrets, dome, arches, etc., as well as the other decorative features, were carried out in concrete.
All exterior walls and all partitions are of hol low partition tile laid in mortar. Plaster is ap plied directly to the tile surface on interior par titions, and elaborate decorations in the lower floors are applied directly to the tile and concrete surfaces.
The entire building—footings, columns, girders, beams, floors, roof, and walls—is of concrete reinforced with trussed bars. The concrete pilasters between windows are 7 feet 6 inches on center ; and each one supports a floorbeam. The columns of the row down the center, dividing the building into two bays, are 15 feet on center. Intermediate beams span 29 feet from wall to center girder and columns. Between these beams is the 42 inch solid concrete floor-slab.