The Golden State: Where & How to Live, Secure, Visit, Enjoy and Thrive in California

How To Design And Install Plumbing

The materials most commonly used for waste, soil, and vent installations, which constitute the part of the plumbing system above the ground, may be cast iron, galvanized steel and wrought, copper, brass, lead or acid-resistant cast iron. Use of any one of these materials usually is determined by the architect's specifications. The factors that should be considered when choosing the materials for the drainage installation are the size and height of the building, the purpose for which the plumbing system is intended, the materials in solution and suspension within the waste, etc.

The fittings used in connection with the pipe vary in design and construction. Fittings used in connection with waste lines must be of long radius and free from interior defect. Vent fittings do not require a long radius, although judgment should be used, because the air within the system is usually moving, and short radius fittings do offer resistance to free flow.

In the following paragraphs, kinds and variety of pipe and fittings are briefly discussed.

Vitrified Clay Pipe. Vitrified clay pipe and fittings generally are used for underground public sewers, house sewers, and drains. They are used commonly for storm as well as sanitary sewer installations.

The pipe is made of clay to which water has been added, and cast into lengths of 2 feet 6 inches. It is equipped with a bell and spigot end so it can be joined. After the pipe has been removed from the mold it is treated with glaze and fired in large kilns under temperatures of 2500°F. to make it impervious to moisture. All vitrified clay pipe used for plumbing installation must meet the requirements established by the American Society for Testing Materials (A.S.T.M.). Vitrified clay pipe must be laid on substantial soil foundation.

If the soil is of an unstable nature, clay pipe will sag and crack readily. This is partly due to the method used in joining the lengths. Should it become necessary to lay the pipe in swampy, unstable soil, an oak plank, or stone or concrete foundation must be provided.