Conditions for Pipe Laying

Type of Pipe

• The basic rule of plumbing is that no two jobs are the same. The type of soil, the climate, the humidity and the type of construction you are working with can all vary. The type of pipe changes depending on if you are installing drain pipes for a septic system, gas lines for a natural gas heating system, a well supply line or an insulation pipe for electrical and fiber-optic cables. Structural engineers are required to build things to code, and only they can determine the exact type of pipe you need for your specific project.

Below the Frost Line

• While not important for pipes that are simply carrying cables, any type of pipe that moves liquids – either to the house or away from the home as with a drain pipe – needs to be below the frost line so that the water in the pipe doesn’t freeze in the winter months and crack the pipe. Only a structural engineer for your city and county will know the exact level for your pipes; he can recommend how far down to go.

Drainage Angle

• Drain pipes require a slope to the actual drain. The minimums differ depending on the local codes, but they range between 1/8- and 1/4-inch of vertical decline for every linear foot of pipe. That means any pipe laid in the ground in a trench needs to slope away from the house according to the minimum code requirements for your area so that the water runs down and out rather than collecting in the pipes.

Size of the Pipe

• One of the other variables for laying pipe is its size, which again varies based on the factors involved in the construction project. Pipes not carrying liquids can be the diameter of the interior components, such as with cable lines, but any drainage pipes need to be large enough to move the amount of water you need for your home. Local codes vary, but as a general rule drain pipes are a minimum of 4 inches in diameter.