For 4-inch pipe 1 in 40 feet " 5 " " 1 " 50 " " 6 " " 1 " 60 "
_Position._--The house drain lies in a horizontal position in the cellar, and should, if possible, be exposed to view. It should be hung on the cellar wall or ceiling, unless this is impracticable, as when fixtures in the cellar discharge into it; in this case, it must be laid in a trench cut in a uniform grade, walled upon the sides with bricks laid in cement, and provided with movable covers and with a hydraulic-cement base four inches thick, on which the pipe is to rest. The house drain must be laid in straight lines, if possible; all changes in direction must be made with curved pipes, the curves to be of a large radius.
_Connections._--The house drain must properly connect with the house sewer at a point about two feet outside of the outer front vault or area wall of the building. An arched or other proper opening in the wall must be provided for the drain to prevent damage by settling.
All joints of the pipe must be gas-tight, lead-calked joints, as stated before. The junction of the vertical soil, waste, and rain-leader pipes must not be made by right-angle joints, but by a curved elbow fitting of a large radius, or by "Y" branches and 45° bends.
When the house drain does not rest on the floor, but is hung on the wall or ceiling of the cellar, the connection of the vertical soil and waste pipes must have suitable supports, the best support being a brick pier laid nine inches in cement and securely fastened to the wall.
Near all bends, traps, and connections of other pipes with the house drain suitable hand-holes should be provided, these hand-holes to be tightly covered by brass screw ferrules, screwed in, and fitted with red lead.
"No steam exhaust, boiler blow-off, or drip pipe shall be connected with the house drain or sewer. Such pipes must first discharge into a proper condensing tank, and from this a proper outlet to the house sewer outside of the building must be provided."
_Main Traps._--The disconnection of the house pipes from the street sewer is accomplished by a trap on the house drain near the front wall, inside the house, or just outside the foundation wall but usually inside of the house. The best trap for this purpose is the siphon or running trap. This trap must be constructed with a cleaning hand-hole on the inside or house side of the trap, or on both sides, and the hand-holes are to be covered gas-tight by brass screw ferrules.