How to Set up an In-Ground Sprinkler System

Setting up an in-ground sprinkler system is a pretty big undertaking, from planning to digging, to installing a complete piping system. Many people try to install a sprinkler system as a DIY project. But before you get started, it’s important to know what kind of work goes into this. The system consists of buried pipe, drip-irrigation tubing, and various fittings and assemblies. There are many factors that can affect how you set up the system.

Before you embark on this journey, let us run through the general steps of planning for and installing your sprinkler system.

Setting Up and I-Ground Sprinkler System

Start Planning

A properly designed in-ground sprinkler system will let you spray water where it needs to go. At the planning stage, consider the type of grass, as some grasses need more water than others, and the soil type (for example, clay soil is less absorbent than sandy soil). If you supply too much water for the soil, runoff can become a problem.

You also need to:

• Check with your city or municipality if a building permit is required.
• Obtain a map of underground utilities, so you know where to dig.
• Look into local watering ordinances; breaking laws can lead to hefty fines.
• See whether local regulations require installation by a licensed professional.

Gather Information About Your Home

You’ll need to know important details such as the size of your water service line, water pressure in pounds per square inch (using a pressure gauge), and the size of your water meter (or pump size if you use a well). Residential water meters come in 5/8-inch, ¾-inch, and 1-inch sizes. Flow rate in gallons per minute must be determined, while you’ll need to check local codes once again for what type of backflow prevention is required.

Create a Map

Now, you can draft a layout of the system. Some of the elements to consider include shrubs, flower beds, trees, sidewalks, fences, slopes, and where your yard is typically sunny or shaded. Depending on these features, and water supply capacity, you may need to create multiple watering zones. Each zone will contain its own independent set of pipes, sprinkler heads, and control valve.

To draw your map, you’ll need graph paper and to measure and map your property to scale; for example, at 1 inch = 10 feet. Include your house, permanent landscape features, and areas that need water. You can also note prevailing winds, the slope of your yard, and where to put the manifold. Create a layout of the sprinkler heads so there’s overlap in the spray pattern and to determine the number of zones, sprinkler head sizes, and styles.

Collect Your Supplies

Gather the parts so you have what you need to get started. The main components of an in-ground sprinkler system include:

• Pop-Up Lawn Sprinkler Heads: Installed below ground level, they retract to avoid contact with foot traffic and mowers.
• Shrub Sprinklers: Taller in height, they are suited for flower and shrub beds; choose height based on the size of mature plants.
• Valves: Open and close to allow water into pipes serving each zone. Each valve is protected by a valve box.
• Sprinkler Heads: Are rated based on the gallons per minute they can supply at a particular pressure; the type needed depends on water requirements.
• Fittings/Couplings/Risers: Tees and elbows connect and redirect pipe, while risers connect water pipes to the sprinkler heads.
• Pipe: The most common sprinkler system pipes include polyvinyl chloride (PVC) or polyethylene pipe.

Other components include the valve manifold, timers, manual controls, and a backflow preventer. You’ll also need pipe cutters for sizing pipe to your needs.

Start Digging

Use stakes and string, wooden stakes, or plastic flags to identify where the water lines will go, starting at the water source to be tapped into. Then it’s time to start digging trenches. For sprinkler systems, these are only about six to 12 inches deep. The trench must be deep enough to avoid frost and to allow sprinklers to retract. Digging can be done by hand using a garden spade with a square edge, or a ditch spade for working in narrow areas. For flower or shrub beds, dig by hand. Gas-powered trenching machines are also available.

*All trenches must be level; uneven areas can cause gravity to work against the system, reducing efficiency.

Assemble and Connect the Pipes

First, turn off your home water meter. Then you can cut into the main water line, using a hack saw or pipe cutter; make sure to smooth out the edges with a knife or fine file. Position the pipe and then at the main line, splice in a tee fitting using PVC cement and primer. Glue a 90-degree PVC elbow onto a male PVC adapter and thread it into the tee fitting.

When installing pipes, place a clamp on each end and insert the fitting before tightening the clam. Each pipe must be aligned based on reference marks. At first, these will be ¼-turn apart, but should align when the pipe is twisted. The cement will spread around the edge and set in about 30 seconds.

Connect the Pipe to the Valve Box

PVC water pipes should be joined to the valve box’s zone valve pipes with 90-degree elbows. You can turn on the water supply once the piping is connected. This will flush any dirt or debris from the system. Then turn the water off before beginning sprinkler installation.

Install the Sprinkler Heads

Attach a pop-up sprinkler at the end of each flexible pipe by pushing the barbed fitting all the way into the pipe. Then remove the cap from the sprinkler and install a spray nozzle. You can now lay out irrigation tubing along flowerbeds and trees and connect it to the pressure reducer and microfilter from the underground pipes. Secure the tubing with plastic ground stakes, about 18 to 24 inches apart.

Complete the Installation

With the main sprinkler system in place, you can now install the backflow preventer, programmable timer, and system controls. Perform a test run to see whether water is reaching every sprinkler and zone and in the right amounts. This also lets you adjust sprinkler heads that aren’t on course, so water is delivered to the right areas.

Call a Professional Plumber If Needed

Planning an in-ground sprinkler system, tapping into your plumbing, and running new pipe requires a fair amount of skill and patience. This project isn’t for everyone. But the technicians and Black Hills Home Services can provide the assistance you need. They’re trained in all aspects of plumbing installation. If you need assistance, request service online or call 888-338-1312 today.