Copyright Goodheart-Willcox Co., Inc. Chapter 21 DWV Pipe and Fitting Installation 317 opening in the wye that will be the cleanout is flush with the top of the finished concrete floor. Check the section drawings for the foundation to determine how much the concrete floor is to be above the footings. It may be nec- essary to stretch a string line to represent the top of the basement floor to obtain an accurate height for the wye. It is better for the wye to be slightly higher than necessary so the cleanout plug can be easily installed and removed. Some digging will be necessary to place the wye and 1/8th bend at the correct elevation. To locate the horizontal waste pipe, stretch a string line from the base of the bathroom stack to the place where the building drain will extend outside the foundation to connect with the building sewer. A shallow trench will need to be dug along this line so that the waste pipe can be installed with the correct slope. A second string line can be run from the base of the kitchen/laundry stack to the point where it will join with the first horizontal waste line. (Refer to Figure 21-1.) This joint must be made with standard fittings, so the intersection should be at an angle of 30° to 45° to allow a standard wye and a bend of the correct curve to be used. Once the location of the horizontal pipe is determined, a trench can be dug to permit its installation. Trenches must be sloped so they provide a fall of 1/4″ per foot of run. Generally, the top of the concrete floor for a basement will be 4″ above the top of the footings. This dimension should be checked so the depth of the trench can be Green Note Minimizing Pipe and Fitting Waste Plumbers can do several things to minimize waste of pipe and fittings. First, and possibly most important, is for the plumber to understand what the job requires and plan the installation to avoid the use of excess pipe and fittings. Saving even a few feet of pipe or several fittings on every job creates large savings during a plumber’s career. following practices help minimize waste: ■The ■ Storing and handling pipe and fittings so they are protected from damage and can be located easily. This practice contributes to efficiency and encourages the use of short lengths of pipe. ■ ■ Checking measurements and calculations before cutting pipe to minimize errors, thus reducing waste. ■ ■■ Using as much of each length of pipe as practical. ■ Selecting the most appropriate fitting rather than combining two or more fittings. Using a reducing tee rather than a standard tee and a reducer is an example of this practice. ■ ■ Recycling any unusable or damaged fittings and short lengths of pipe. Can you think of other things you could do to mini- mize amount of pipe and fittings that are wasted? determined. A short trench will also be needed for the floor drain to connect to the 2″ pipe using a wye. 21.3.1 Installing a Stack While the trenches are being dug, work can begin on the stacks. First, consider the kitchen/laundry DWV piping. Figure 21-5 provides a sketch of this pipe and fittings to be used. The names and dimensions of the fittings are given in the table included with the sketch. Code Note IRC Note IRC Chapter 30, Section P3005.2, describes the requirements for cleanouts. These requirements address changes in direction, maximum distance between cleanouts, and size and accessibility of cleanouts. Details are given regarding each of these topics. Goodheart-Willcox Publisher Figure 21-5. Schematic drawing for laundry/kitchen stack. Table identifies the fittings needed. A B D C E F H D G To 3 × 3 × 2 wye F F 2° 1½° 1½° 2″ 2° 1½° 2° Label Quantity Description A B C D E F G H 1 1 1 2 1 3 1 1 2″ floor drain 2 × 2 × 2 wye 2″ long-radius 90° ell 2 × 2 × 1½ san. tee 1½″ P-trap 1½″ 90° ell 2″ test tee w/ cleanout plug 2 × 1½ × 1½ san. tee