How to Install an Automatic Sprinkler System

You’ll no longer have to stand outside with a hose in your hand to water your lawn with an automatic sprinkler system. Better yet, if you set it up properly, you’ll be able to distribute the water evenly and ensure the best care for your grass.

In this video, This Old House landscape contractor Roger Cook walks us through how to install an in-ground irrigation system. Along the way, he shares helpful tips such as how to select sprinkler heads with enough reach or what city or state code to keep in mind during your own setup.

Sprinkler System Installation Step-by-Step

1. Use a pressure gauge to determine the water pressure coming from hose bib (minimum requirement: 30 pounds per square inch).
2. Calculate the water flow from the hose bib by timing how long it takes to fill a 5-gallon bucket.
3. Measure the distance between sprinkler spray heads and insert flags to mark their locations.
4. Dig a 6 to 8-inch-deep trench, then cut 1-inch-diameter polyethylene pipe to length; bury the pipe in the trench.
5. Slide a 1-inch metal hose clamp onto the end of the 1-inch pipe, then heat the pipe end with a propane torch.
6. Press a barbed fitting into the end of the softened 1-inch pipe, and tighten the hose clamp with crimping pliers.
7. Attach a short length 3/8-inch flexible pipe to the sprinkler head.
8. Heat the opposite end of the flex pipe and force it onto the barbed fitting attached to the 1-inch poly pipe.
9. Set the sprinkler head into the trench and backfill around it.
10. At the next head, insert a T-fitting into the 1-inch poly pipe, add length of flex pipe, and install another sprinkler head. Continue in this manner to add more heads.
11. Grab the orange cap on the sprinkler head and pull to extend the riser; remove and discard the orange cap.
12. Push a filter down inside the head to prevent dirt and debris from clogging the nozzle.
13. Screw the nozzle onto the riser.
14. At the hose bib, install a backflow preventer and a battery-operated timer.
15. Place a 1-inch metal clamp over the end of the 1-inch poly pipe, then use the torch to heat the pipe end.
16. Force the heated hose end onto the timer, and crimp on the clamp for a watertight connection.
17. Turn on the water and test system to ensure all the sprinkler heads pop up and disperse water.

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