How to Lay Pipe for Outside Plumbing

There are several reasons you may need to run plumbing pipes outside. The plumbing may be needed for a sprinkler system or to provide facilities to an out-building. Whatever reason you have for installing plumbing pipes outside, it must be done properly to avoid future problems. The main consideration when installing outside plumbing is to bury it below the frost line, which in most areas is 32 to 36 inches.

Things You'll Need

• Wood stakes
• String
• Power trencher
• Ax
• Yard stick
• Gravel
• Shovel

Instructions

1. Select a route to lay the plumbing that will provide the least chance of being obstructed by tree roots or other impediments.

2. Pound wooden stakes into the ground along the chosen route every 3 to 4 feet and connect the stakes with string. This will provide you with a guide to follow as you dig the trench.

3. Dig the trench using a power trencher that will dig to a depth of 36 inches. You can rent the trencher at most tool rental stores. Follow all the safety and operating instructions for the particular trencher that you rent. Start at one end of the route and follow alongside the string on the stakes. Measure the trench with a yard stick as you dig to ensure the proper depth. Use an ax to chop out any roots you may encounter.

4. Fill the bottom of the trench with about an inch of gravel and smooth it out to make it as level as possible.

5. Lay the plumbing pipes on top of the gravel and backfill the trench with the dirt that you removed with the trencher.