The elevation of the plumbing for a two-flat house, with pipe sizes given, is shown on Plate 33. In general, the plumbing on buildings of this class is confined to the kitchen sink, laundry tubs, and three bath-room fixtures. Although not shown in Plate 33, owing to lack of sufficient space, flat buildings of all classes should be provided with refrigerator drainage. Usually in flat houses of two or three stories, a 4-in. bath-room stack and a 2-in. kitchen stack is required, although in some cases the 4-in. stack can be made to serve all the fixtures, obviating the use of a second stack. The use of two stacks is better, however, as separate entrance into the stacks can be gained for each fixture, which would be very difficult if the five fixtures entered one stack. In two- or three-flat houses the laundry tubs are sometimes located in the cellar, against which there is no special objection, if the cellar is well lighted and ventilated, except the matter of inconvenience to the tenants on the upper floors. In Plate 33 all fixtures have separate waste entrances, and it will be noted that the kitchen fixtures are served by the special method described and illustrated in Plate 27.
Plate XXXIII. Plumbing For Two-Flat House -Rainleaders - Plumbing Construction For Tenement Houses
Two-Flat House.- No Main Trap
It will be noted that the water closet on the upper floor is not vented. There is in reality no danger whatever of the siphonage of the water-closet trap when the fixture is located close to its stack, with no fixtures entering the stack on floors above, and therefore there is no necessity of venting it. Most plumbing ordinances acknowledge this fact by not demanding the venting of water closets thus located.
In connection with this plate, the subject of rain leaders will be considered.