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CHAPTER I.

CONSTRUCTION

There is no such thing as fireproof construction. There is a class of construction termed "fireproof," but its analogous (so accepted) term, "superior," more properly expresses what is meant by this class of construction. Wood will burn, iron and steel will bend and give way under the action of heat, and they also tend to destructively contract when they are overheated and have cold water suddenly thrown on them; stone tends to disintegrate under the action of heat and water, and buildings have not yet been built of fireproof térra cotta or brick, nor of glass, and so it is that there are no actual fireproof buildings. But there are buildings so constructed that the liability of their destruction by fire is practically reduced to a minimum; but it is not intended to suggest that the contents of such building are not liable to burn. A “fireproof" or "superior" construction is to a great extent thought to imply that the contents will not burn; this idea is as silly as it is impossible. The idea in this class of construction, termed "fireproof," is to reduce the liability of a fire commencing in such a building from spreading, not only to some other building, but from the location in which it starts to some other part of the building, and it has been demonstrated, that this result has been reached to a very great degree. But the water and smoke damage in such a building cannot be entirely eliminated. The water damage can be reduced to a considerable extent by pitching the floors and providing drains for each floor, so that the water on one floor will not necessarily run down to the floor below.

In "mill" construction there has been reached a high degree of construction which, while not fireproof, as all of the interior is of wooden construction, still is of such a class that a fire does not easily destroy the wood, and from the fact that there are no concealed spaces nor draught spaces, a fire cannot develop nor spread rapidly, and the chances of extinguishment are very much increased. Buildings of this construction are

never built as high as are buildings of the so-called "fireproof" class, but for the purposes of manufacturing plants they are preferable.

"Hollow-spaced" construction is, of course, the poorest class of construction from a fire insurance standpoint.

CONSTRUCTION.

For general descriptive purposes construction can be divided into three classes, i. e., "fireproof" ("superior"), “mill" ("slowburning"), and "hollow-spaced."

"FIREPROOF." ("SUPERIOR CONSTRUCTION”)— The characteristics of this class are a bridge construction of steel; a framework for walls and floors, riveted together and making a self-sustaining rigid frame. The walls, preferably of brick, are built over and around the skeleton, in some cases being self-sup porting and in others receiving support from the framework of steel. The floors are usually made of terra cotta arches sprung in between the steel girders and thoroughly covering them, and having a top finish of concrete on top of which the flooring of tiles or narrow wooden flooring is laid.

The partitions throughout are of fireproof brick or tile; the stairs and elevators are in hallways cut off from the remainder of the building by fireproof partitions; the framework, and all parts of the stairs and elevators being of steel and stone.

The exposed metal at the stairs and elevator should be the only exposed metal in the entire building, the posts being covered with fireproofing the same as all other parts of the construction steel.

The roofs are of the same construction as the floors with the exception that they have no wooden flooring top finish.

"MILL," or "SLOW-BURNING."-The main idea in this class of construction is that there shall be no hollow or concealed spaces whatever, and that there shall be no openings in the floors.

Walls are of brick, 12 inches at the top floor and 4 inches thicker at each second floor for outside walls, and for division, party or cut-off walls 4 inches thicker than the outside walls at each floor: all exposed outside walls and all party walls to be 3-foot parapet, i. e., to be 3 foot higher than the con

tiguous roofs; division walls to be corbeled sufficiently so tha they will extend beyond the outside line of the roof overhang or cornice.

Stairways and elevators to be in brick towers or shafts, the walls of which rise 3 feet, at least, above the roof of the building. The roofs are of the same construction as the floors excepting that they need be only 3 inches thick, and covered with gravel, metal or approved composition.

The floors are double, the first layer being of 3-inch splined planking and the top flooring one-inch matched boards with two thicknesses of waterproof paper between them. The boards and planking should preferably be laid diagonally. The beams are of solid wood supported by ledges in the walls, a proper corbeling or iron wall plates, and by wooden posts; the beams must be cut on a splay at the wall bearings so as to make them self-releasing, in order to prevent the walls being pulled down in case of a beam falling. The posts are placed one over the other throughout, and are provided with cast iron caps pintles and base plates, the beams setting on the plates and being self-releasing.

The outside wall top finish should be the roof overhang, un boxed, or a brick, stone or terra cotta cornice.

Stairways may extend through floors between two floors, bu they must be of incombustible material and must be enclosed ir. fireproof enclosures of brick, terra cotta, concrete, or iror. frame with metal lathing plastered on both sides.

All communicating openings in walls to be provided with double-standard tin clad fire doors or shutters, and all exposed openings to have standard tin clad fire shutters on them. All shaft, belt, flue and trunk holes to be as small as possible, either by being bricked up or by being provided with standard fire shutters or metal hoods.

For additional rigidity and strength, girders can be placed between the floor beams, but these girders must rest in iron stirrups at their ends.

The following variations from these rules are found to a con siderable extent in so-called "mill" or "slow-burning" construction factories: Elevators inside the building with automatic traps at each floor; inside stairways enclosed in wooden parti

tions or with automatic acting traps at the upper landing of each flight of stairs, the material of the stairs being wood; open belt holes in floors; outside walls, pilasters with large windows between.

"HOLLOW-SPACED." CONSTRUCTION.-This class includes dwellings, the ordinary stores, business blocks, office buildings, hotels, etc., whether built of brick, stone, or wood, although there are now many exceptions in the larger cities in the construction of office buildings, large stores, and other business blocks and some hotels.

In this class of construction the interior finish is of laths of wood or expanded metal, wire netting covered with plaster, or of wood ceilings; the floor construction being of wooden joists with single wooden flooring above them and laths and plaster, or, in some comparatively few cases, stamped steel on the under side to form the ceiling for the floor below, thus leaving hollow enclosed spaces between the flooring and the joists and the ceiling below; the walls are finished in a similar way with laths and plaster and hollow concealed spaces are formed between the walls and the lath and plastering; these spaces in a majority of cases running from floor to floor without any breaks from the lowest to the highest story of the building.

The main point to be looked after as an improvement in this class of construction is the cutting off of draught spaces, i. e., continuous concealed spaces in the floorings and walls. In the floor spaces this can be done by setting “stops" or "breaks" in the horizontal concealed spaces; these "stops" can be of planking, which same when properly set will cut off any rush of air or draught. In the walls, the building laws of New York city call for all furred walls to have a course of bricks above the under side and below the upper side of each tier of floor beams, projected out the thickness of the furring, to more effectually prevent the spread of fire from floor to floor in this hollow space; in order to remedy this defect where already in the construction, the space between the flooring and the wall itself (not to finish of the wall, but the wall itself) should be filled in so as to absolutely cut off the continuous hollow space at this point; this will prevent draught and retard the progress of fire from floor to floor at this place. While a building is in course of construction

"breaks" can easily be made by filling in spaces at floors with old bricks and mortar held close against the walls by confining strips set in between the joists.

A building well finished with plaster is better than one with a wood inasmuch as there is not so much material to carry a fire or for a fire to feed on.

The "hollow-spaced" construction is the worst form of construction.

WALLS.-Walls should preferably be "blank," i. e., without any openings whatever in them.

Independent walls with exposed openings should have the openings protected with standard fire doors or shutters, wired glass or prism glass.

Party or division walls having openings in them should have the openings protected with standard fire doors.

All walls, wherever possible, should be fire walls.

A fire wall is one of stone, brick, or terra cotta, extending 3 feet above the contiguous roofs' level, i. e., parapet, stone, terra cotta, or cast iron coped, "blank" or with all the openings in it protected by standard fire doors or shutters, and with a proper thickness of wall (a "proper thickness" to be judged not only by the height of the building, but also by the uses of the rooms or buildings on each side of the wall where buildings are using the wall as a party wall, or where the wall is a division wall); if the fire wall is a division wall, or an independent wall exposed to other buildings, it should be corbeled a sufficient distance so as to extend beyond the line of the cornice of the building.

All stone or brick division or party walls, and all stone or brick exterior walls directly exposed to outside buildings of less or equal height, or of greater height (when not over 2 feet), should be raised from 2 feet to 3 feet above their roofs' levels, thus making parapet walls, and should be capped with stone. terra cotta, or cast iron.

Partition walls should, as far as possible, be of brick, tiles, plastered wire netting, or single boards unceiled; where wood scantling is lath and plaster it should be filled in between the scantling with brick.

Where wooden buildings have sides or ends exposed to other

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