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the bridging of partitions; this will cause any fire which may have started below to break out in the lower room, where it will be discovered before it is likely to reach the story above. The spaces between stair stringers and around chimneys should also be protected by fire stops of brick or plaster.

OTHER OPERATIONS CARRIED ON WITH FRAMING

Framing Details. As soon as the roof is on and boarded, the gutters will be put up and the roof shingling begun. The position of the gutters must be carefully noted to be sure that the edge is on a line with the roof boarding, for otherwise the gable finish will not work out correctly. The position of the conductors should be determined, and the gutters set with a slight fall toward them, and holes for the lead goosenecks should be bored, in order that no water shall stand in the gutters. With the completion of the gutters the shingling or slating of the roof can be commenced, and before the roof is completed the furring of the inside will be discussed.

Fig. 34.

Horizontal Bridging of Partitions

Beyond the setting of minor partitions which were not needed for the support of floor beams, the principal work of interior framing will be the furring of chimney breasts, and the forming of beams and arches. The position and size of every door must be carefully verified, especial care being taken to allow the proper width for door casings where doors come close to the corner of any room. When the studs of all interior partitions are set up they must be bridged. This is often done by cutting in horizontal pieces between the studs, Fig. 34; but a better way is to cut in the pieces diagonally, Fig. 35. The chimneys must be enclosed by vertical studs, usually 2-X3-inch or 2-X4-inch, set flatways and at least an inch away from the brick, Fig. 36, with an ample, well trussed opening left for fireplaces. All door openings must also have a truss over them, and

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any partitions which have no adequate support beneath should be trussed, if the arrangement of doors will by any means allow it.

The ceilings will be cross-furred with -X3-inch strips, commonly called "strapping". These strips should be carefully leveled

Fig. 35. Diagonal Bridging of Partitions

and straightened, since upon their evenness depends the smoothness of the ceiling; above all it is necessary that the strips be well nailed to every joist. Grounds are next set and angle beads for lathing,

B

B

Fig. 36. Typical Section Showing Chimney Furring

but before any laths can be laid there are a number of things to be considered.

Furnace Pipes. In the first place, all hot-air pipes which are not to be exposed must be put in position. If a hot-air system has

been selected, the position of the pipes and registers will have been marked on the plans, but frequently in the execution changes suggest themselves or are required by unforeseen circumstances, so that the superintendent should make a personal study of the piping at the building. Where it is possible to arrange it, the pipes should be run through closets, exposed to view; but this cannot always be done, and it often happens that the chimney breasts and sometimes the partitions must contain hot-air pipes. The best and safest way to do in that case is to make the pipes double with at least a halfinch air space between the outer and inner pipes. This is expensive and is not generally done; instead, the woodwork which comes close to the pipe is lined with bright tin, and heavy wire lathing rather than wood laths is used in front of the pipes. Where the pipes are carried through the partition or woodwork, a sleeve of bright tin a half-inch larger than the pipes should be provided as a safeguard against the overheating of the pipes.

Ventilation and Gas Pipes. Although it is customary nowadays to run the plumbing pipes outside of the plaster, there are some ventilation pipes that need to be provided for at this time. All of the enclosed gas-piping must be done before lathing. From the fact that the gas-piping must be carried in almost every case to the center of the ceilings, there is need of careful watching lest the cutting by careless workmen weakens the joists. The specifications distinctly state that no floor beams shall be cut into, more than 2 feet away from their bearing, but as this means that all outlets in the centers of ceilings must be reached by branch pipes between the joists, and as this entails more piping and labor for the gas-fitter, there is a great temptation to disregard instructions and to cut the joists for a straight run from center to center of rooms. Only constant watching will prevent this being done. Care must be taken that the pipes are run with a continuous drop toward the meter, to allow the liquid, which is always condensed from the gas, to run off; and, for the same reason, wall outlets must be piped up from below, and ceiling drops should be taken out of the side or top of the pipes. The position of all outlets must be verified, especially those which are centered in the rooms, and they must be set at right angles to walls and ceilings. This can be proved by screwing on each outlet, as soon as set, a piece of pipe a foot or more in length and testing with

& stee square. No "gas-fitters"" or other cement should be allowed, but all pipes should be put together with red lead. The outlets to receive fixtures should be strongly secured to prevent springing or movement in the plastered work.

Testing. When the piping is all in place, the outlets are to be capped and the whole system tested for leaks, and then accepted by the local gas company. The test consists, briefly, in attaching to one of the outlets a mercury gage, and then filling the pipes with air under pressure till the mercury in the gage stands at the height

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required to insure tightness, which is usually 6 to 12 inches. The apparatus is then left to stand for 10 or 15 minutes, and if the mercury at the end of the time holds the same level it is safe to say that the pipes are tight. Leaks may usually be discovered by the sound of the escaping air, but often ether is put into a cup attached to the pump and forced in with the air, so that leaks, especially in concealed parts of the piping, may be detected by the odor. Suspicion of a leak in pipe or fittings may be verified by brushing strong soap water over the place; if there is a leak, a bubble will be blown by the escaping air. Small pinholes in the pipe or couplings

may be tamped and if thus rendered tight will remain so, but pipes showing a split or large hole must be replaced.

Vacuum-Cleaning Pipes. At this time also pipes should be run for a vacuum cleaner if the system is to be installed, and in any case it is a good plan to put in a line of pipe from cellar to attic as the expense is slight and pipes run at this time can be concealed. While portable cleaners are very efficient and easily handled, they are not so convenient as a basement machine which requires only hose connections in each story.

WIRES

KNOB

TUBE

Care should be taken that outlets are centrally located and that the outlet pipe joins the main pipe by an easy sweep, Fig. 37, and not with an elbow or T-connection. As the piping varies in detail for different machines, it is well to consider some particular make and pipe according to the manufacturer's recommendations. The methods of starting and controlling the machine from distant points should be considered, and the proper connections, electric or otherwise, installed.

Electric Wiring. All counFig. 38. Electric Wiring Placed in Framing try houses, unless in very remote situations where there are no chances of an electric current ever being obtained, should be wired for electric lights. There are at least three methods of installation, the usual one being the knob-andtube system, in which the wires, of copper heavily insulated, are run on porcelain knobs between beams and studs, and in short porcelain tubes where passing through timbers, Fig. 38. Although the insurance exchanges employ inspectors and require that every job of wiring shall be reported to them and inspected by their men, it will be well for the superintendent to watch carefully this construction to see that all wires are thoroughly insulated and at least 3 inches apart to avoid any chance of contact; that they are not

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