How to Set Up an In-Ground Sprinkler System

An in-ground sprinkler system with a programmable timer helps you maintain a healthy lawn without excessive watering. You’ll need to connect the control box and antisiphon valve wires to your main water line.

You’ll also need to know the size of your water meter or well pump (check the owner’s manual if you can’t find it). Use poly pipe that matches the line sizes.

Start with a Plan

A well-planned sprinkler system will ensure your lawn is watered evenly and at the right times. The first step is to map your yard and identify major features such as walkways, fences and existing flower beds. Also, be sure to note any slopes.

Figure out your home’s flow capacity, commonly referred to as GPM (gallons per minute). You’ll need this information when selecting pipes and other components.

You’ll need a backflow preventer, which is required by local codes. It is usually installed higher than any sprinklers. You’ll also need a valve manifold, piping, sprinkler heads, timers and a rain gauge. A programmable timer is recommended as it will ensure your yard stays eco-friendly by keeping your lawn on a set schedule, and will save you money on your utilities bill by shutting down during rain events.

Dig Trenches

Once you have a plan and know where each sprinkler will go, dig the trenches. It is helpful to use a garden spade, a ditch spade, or a power auger for the job.

If your lawn is heavy with sod or has hard soil, water it the day before digging to soften it and make the work easier. It is also a good idea to hire someone to mark underground lines before you start digging to prevent severing any important pipes or wires.

Once the trenches are dug, roll out your poly pipe (typically 19mm for domestic lawns). Make sure to connect a control valve to each section of the pipe and a sprinkler head to the end of the poly pipe. Also, install a short length of “swing pipe” or “funny pipe,” between the end of each sprinkler and the rigid poly pipe to allow for movement.

Connect Pipes

To prevent damage during digging, check with your local water authority for a map of underground utility lines. Obtain a permit if required.

Pipes connect to a manifold in the ground, which in turn feeds individual zones. A programmable timer helps ensure that your lawn is properly watered at regular intervals, saving you money and keeping the turf healthy.

At the end of each length of poly pipe, install a pop-up sprinkler head using a barbed fitting (push it all the way in). We equipped this system with spray heads for the grass, rotary heads for larger areas and a bubbler to soak flower beds without wetting leaves.

For continuous runs of pipes, use self tapping saddle valves to tap into the pipe. These can be found at most home improvement stores.

Install Sprinkler Heads

Use an inexpensive pipe cutter (available at most hardware stores) to cut the sprinkler head risers to size. When you cut the pipes, make sure to leave reference marks so that when you reinstall them you can connect them properly. Then install the sprinkler heads in their intended locations. To get good coverage, each head should overlap its neighbor by about 50%.

When a head is connected to the poly pipe with a fitting, consider using a length of funny pipe, also known as rubber hose, between the end of the sprinkler and the fitting. This allows for easy positioning of the head, and reduces the risk that if someone steps on the head it will crack the fitting that attaches it to the pipe.

Test the System

Once all the zones are filled and air bubbles are pushed out of the pipes, turn off the water at the valve box. Check the controller timer settings to make sure they meet your lawn and landscape’s spring watering needs.

If you are using a traditional controller, consider adding a rain sensor. This will shut the system off when it rains and also adjust your watering schedule for the following week.

You can either hook up your sprinkler system to a spigot that has adequate water pressure or tap into your home’s main water line. If tapping into your main line, call in a professional to help you cut into the pipe and ensure that you don’t sever or damage any existing pipes. Also, be sure to have your local utility companies mark all underground lines a few days before beginning this project.