Columbia University Libraries Digital Collections: The Real Estate Record

Real estate record and builders' guide: [v. 94, no. 2421: Articles]: August 8, 1914

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REAL. ESTATE AND ■-■ NEW YORK, AUGUST 8, 1914 'Piiiiiiiijiiiiiiiii PHILADELPHIA TOWER FIRE ESCAPE History of Safety Tower From Its Infancy—Examples of Practicability In Cases of Fire—Space Always Utilized.* By MANTON E. HIBBS, C. E. giliiiiiilllililliiiliiliiWIliiiiM^ JiiliiiMiilliilM^^^^^^^^ ......iiHil......ii.....iiiiiii "T^HIS age is demanding from science *• a very heavy toll of duty, especially along those lines affecting specifically the human element and its welfare. A fire takes place in one of our large buildings and, for the same reason, all are concerned for the safety of its oc¬ cupants. In nearly every disastrous fire that has taken place, there seems to arise a wail for more fire-escapes, to the total exclusion of the ordinary means of exit. In order that all might get a grasp as to how Philadelphia is solving the problem of adequate means of exit in matter of panic or fire, as well as for ordinary use in her buildings, attention will be first drawn to the history of the tower, for its building, like any other mechanical device, is an evolution ex¬ tending over a period of twenty years or more. First Type to Be Used. Probably the first kind erected many years ago was simply a vertical, metal ladder available for exit at windows with no platform at the story heights. This was replaced by fixed platforms covering two windows with immovable stairs at an angle of 45° more or less, with a movable, vertical ladder reaching from the second floor to grade line. Then came the substitution of a mov¬ able, hung stairway, counterbalanced by a weight attached to a chain or cable .for the vertical hung ladder from the second-story landing. In the next step, this stairway was counterbalanced in the rear like a can¬ tilever. The platforms are usually of slats, channels and angles carried on brackets bolted to the walls by through bolts. It will be noticed from this evo¬ lution that the main development has been that a stairway and platform growth, with little or no attention paid to the means of reaching the fire-escape, which was, in most cases, from windows placed 3 feet above the fioor. Recently, the Pennsylvania Legislature passed a law, making it mandatory that the en¬ trance to the fire-escape platform should be by a fire-door, and all the windows covered by the escape must be of wire- glass and metal frame. Tower Fire Escape Born. The tale runs that a Kensington mill owner of Philadelphia was ordered by the Building Bureau to put up an out¬ side metal escape on one of his build¬ ings. ■ Upon consultation with his archi¬ tect, the idea of eliminating outside stairs of the escape by taking the or¬ dinary stairs of his building and en¬ closing them in a tower of brick, there¬ by separating the stairs entirely from the re^t of the building, was evolved. This forced, of course, an entrance to the tower from the outside of the build¬ ing by means of the platforms of the outside metal escape, which were reached from the main building by doors, at every story, opening upon the plat¬ forms. The Bureau agreed to this, and the tower fire-escape was born. ♦Excerpts from a paper read at the First An¬ nual Convention of the American Society of En¬ gineers, Architects and Constructors. Under the Act of June 8, 1893, the tower fire-escape was taken as an equivalent for a metal escape and was required for mills and stores only. Later on, this same mill owner, upon advice of his architect, submitted to the Bureau a proposition that, in place of the mitside platform, a vestibule be sub¬ stituted with one side open entirely to the air. The Bureau consented only on the condition that if the experiment was not a success the outside platforms would have to be added. However, it was successful. Towers Installed. Under the Act of May Sth, 1899, stores and manufacturing establishments were compelled to install towers, and if the areas exceeded 10,000 square feet of floor, additional towers could be or¬ dered. This, of course, applied to build¬ ings three stories or more in height. Under the Act known as No. 236, of the date of April 25th, 1903, which is now in force in Philadelphia, all buildings of first, second or third class used as school houses, tenement houses, apart¬ ment houses, flat houses, stores, oftices (first class exempt), manufactories, workshops, mills, places of assembly or resort,^ of three stories or more, shall have in addition to the main stairs tower fire-escapes, whose number de¬ pends upon the character of construc¬ tion of the building, the number of sto¬ ries and the area of the floor. Features of Construction. A formula for the construction of the tower fire-escape was evolved and has as main features the following: The tower fire-escape shall be divided from the building and completely enclosed with brick walls or fire-proof material; the walls must run 3 feet above the roof of the building and the roof must be of hard, incombustible material, thus the tower becomes sinoke-proof as well as fire-proof. The stairs may be of metal or wood with a rise not more than 8 inches and the tread not less than 9 inches. The entrance to the tower must be by means of an outside balcony, whose floor is of solid, incombustible material through a metal or tin covered door or by means of an incombustible vestibule, one side of which is entirely open to a street or alley, and there must be also a well, separating the vestibule from the tower. The vestibules, walls, floors, ceilings, must be entirely of hard, incombustible material. Meeting Architectural Needs. Now, having placed in the building code the clause making nearly every kind of building that formerly required a meta! escape have a tower fire-escape, also adopted a formula for its construc¬ tion, then came the task of adapting the tower to meet the architectural and commercial needs of the building. The tower can be used, especially if it has a vestibule, as an ordinary sta'irway at all times. In the Wanamaker build¬ mg, whose floor area is 112.608 square feet per floor and whose height is 243 feet, the four double fire-towers are al¬ ways used by the employees, and that is the only way of entrance or exit for them. Hence, all are familiar with them, and, in case of emergency, their value is not an unknown asset to each worker. Saving Space. As the stairway leads from the sec¬ ond floor directly to the street, it was only that space occupied by stairway necessary for tower, while one-half the tower of the first floor, and all below first, was really wasted as far as utility goes. To make this space available as an entrance to the elevator in rear, or as a stairs to the cellars, a wall was run from the basement to the landing above the first floor, while the stairs to the second floor and basement were made fire-proof. An entrance could not be made in the main wall of the tower on the first floor, and if a fire breaks forth in tlie cellar, the smoke ascending will Ije blocked by the fire-proof stairs and middle wall and the tower is still smoke- proof as if the walls were still run solid to foundation. The fire-tower is especially adapted to theatre construction. Often, emer¬ gency exit platforms are forced beyond the street lines, which can be readily done above the first floor, and if a fire- tower can be built to cover the second floor only, these exits can run to the tower thus preventing any encroach¬ ment of the sidewalk. At the Phila¬ delphia Opera House and the Orpheum Theatre, vestibules extend along the lines of the balcony, and by these ves¬ tibules, the people are readily led to the tower and thence to the street. In the Philadelphia Theatre Law, if towers are constructed for the use of emergency exits, the courts along the sides of the theatre are allowed to be decreased. Apartment houses and hotels use their tower fire-escapes in conjunction with their kitchens for supplies and a ser¬ vants' exit. Saving Money. The factories have placed their eleva¬ tors in the rear of towers, thereby sav¬ ing one side in cost of construction. Also, by running the walls 20 feet above roof and increasing the walls below tank positions for their sprinkler sys¬ tems. Sometimes, these factories have more than 25.000 square feet of floor area and division walls are necessary with no openings. In place of the usual openings with double fire-doors, a double fire-tower can be constructed on the outside of the building, and work¬ ers can readily leave the two buildings without making a journey to another stairway. In case of fire, the tower be¬ comes a means of advantage for the firemen to reach and fight the fire at every story with perfect safety. In fact, in one fire in Vine street near Broad street the only thing that was left was the fire-tower. Our architects have woven the towers renrlily into our structures so that no buildins* need be marred or disfigured in -the same way as the outside metal es¬ capes. In some instances, by a little thoughtful decoration in the matter of a balconv. or by window boxes of floors, a touch of the city beautiful is added to our streets. In the matter of cost, which seems to