The drainage system shall be what is known as the 2-pipe system, which shall consist of a special vent stack accompanying each soil or waste stack. The vent stack shall be connected to the soil or waste stack by means of a Y fitting below the lowest fixture discharging into the stack, and may be connected to the soil or waste stack above the highest fixture discharging into it, or it may extend separately through the roof. All soil and waste stacks shall be extended 5 feet above the roof.
Where soil, waste, vent or supply pipes pass through the roof of the building, the joints shall be made tight by means of 8-pound sheet lead flashings, which shall extend at least 6 inches on all sides of the pipe, and shall be made water-tight where they come in contact with the roof.
The plumbing contractor shall furnish all material and labor to build, where shown on the plan, a "maximum" "fosa moura" according to the requirements of the Havana Sanitary Code. The fosa moura shall be circular in form, 8 feet in diameter, 6 feet 6 inches deep, and shall have walls and bottom of brick, the walls 8 inches thick and the bottom 4 inches thick. The walls and bottom of the fosa moura shall be made water-tight by means of a coating of Portland cement mortar 1-inch thick mixed in the. proportion of one of cement to two of sand. The top of the fosa moura shall be arched over with bricks laid in cement mortar, or shall have a deck of reinforced concrete, with a 20-inch diameter air-tight manhole and cover securely set in place.
The use of lead pipe shall be restricted to the short branches of soil, waste and vent pipes required for the roughing-in of the bathrooms. No lead pipe smaller in diameter than 1 1/2-inches shall be used, and all pipe shall be equal to the grade known to commerce as D and shall be of the following weights: l 1/2-inch pipe, 3 pounds per foot; 2-inch pipe, 4 pounds per foot; 3-inch pipe, 6 pounds per foot, and 4-inch pipe, 8 pounds per foot. Lead bends for closets and slop sinks, or straight connections where bends are not used, will be provided with corrugations to compensate for shrinkage or settlement of stacks or building. All connections between lead pipes or between lead pipe and brass ferrules shall be made by means of solder wiped joints.
The entire drainage system within the building shall be tested by the plumbing contractor in the presence of the sanitary inspector of the city of Havana. Two tests shall be applied to the system; the first shall be a water test and shall be applied by closing all outlets below the roof and filling the drain, stacks and branches, until the water overflows from the vent pipes above the roof. All leaks or defects shall be made perfectly sound and tight and the work shall not be passed until the entire system remains full of water for two hours without leaking.
After the fixtures are all set and the traps sealed with water, a smoke test shall be applied, and any defects or leaks disclosed by this test shall in like manner be made tight and strong. All tests shall be made by and at the expense of the plumbing contractor.
All water-closets and slop-sinks shall be provided with flexible metal-to-metal brass floor flanges, which shall be securely soldered to the lead bends. The adjusting threads of the flange, where they come together, shall be well lubricated with Dixon's Graphite.