Essentials of Plumbing Lesson

INSTALLING DRAIN LINES AND STACKS

The building's drain line connects to the building sewer pipeline and continues to the point where the stack is to rise vertically. The building's drain pipe must be the same size as the building sewer pipe.

Installing the Building Drain Line

Installing a drain line under a foundation floor. Use the following steps:

Place the piping in a trench, one length at a time. Start at the building sewer pipeline and work towards the place where stack will be installed.
Set the pipe to a grade slope of ¼ inch per foot with a carpenters level. The slope will rise from the building sewer line to the stack.
Support the pipe at each connection to maintain the grade slope.
After all the pipes are set, make the joint connections. Use a ¼ bend, long sweep fitting at the location where the stack will be erected.

Installing a drain line under a foundation floor.

Installing a building drain line through a foundation wall. Use the following steps:

Starting at the building sewer pipeline and using the proper grade slope, determine where the foundation wall will be cut. Mark the wall and then cut the hole.
Run a chalk line from the hole to the proposed location of the stack, still using a rising grade slope of ¼ inch per foot.
Place each length of pipe along the chalk line. Support the joint connections with hangers.
Place a 90-degree Y fitting to form the bottom of the stack.
Support it from the bottom.
Check pipe alignment and make the joint connections.
Patch the foundation wall where the pipe runs through.

Installing a building drain line through a foundation wall.

Installing the Stack

Sections of the stack. A combination of vertical pipes with fittings forms the stack in a plumbing waste system. It is used for waste disposal and venting. The main stack is composed of three sections—the soil stack, waste stack, and vent stack. A soil stack carries waste disposal from water closets. A waste stack carries waste disposal from all other fixtures. A vent stack provides air circulation throughout the waste system and allows for the release of sewer gases.

Placement of the stack. The stack runs in the building wall, up through each floor, and out through the roof. It is installed after the building framework is in place. Use the following steps:

Use a plumb line to insure the stack will be vertical.
Cut holes in the framework for running the stack vertically.
Set the pipes in place.
Support the fittings.
Be certain the vent stack rises at least 12 inches from the highest point of the hole cut through the roof.
Place cleanouts at possible waste stoppage points.
Make the joint connections.

Placement of the stack.

Connections to the stack. Branch lines are for disposal of wastes. All rough-in horizontal branch lines in the waste system must slope ¼ inch per foot toward the stack.

Connections to the stack.