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Sprinkler System Installation

The process of installing a sprinkler system for a lawn, save thousands of dollars by installing them yourself.

Every homeowner dreams of a wide stretch of lush, green grass that kids and dogs everywhere will want to roll in. 

A healthy lawn is a joy to the senses and adds value to your home.

But turning a patch of grass seeds or sod into something spectacular requires a lot of time and money. 

Beautiful lawns crave plenty of nutrients, mowing, aeration, weeding, and, most importantly, a consistent amount of water. 

And if you’re tired of arguing with your partner about whose turn it is to drag out the garden hose, you may be ready to upgrade to an automated irrigation system.

At our house, the front yard had sprinklers, but they were not automatic and the backyard was completely abandoned. 

After years of manually turning on the valves or pulling the hose out for yet another long watering session, we decided it was time to redo our sprinklers. 

We are not professionals but we took on the challenge and this is the process we used for a sprinkler system installation.

SIDE NOTE: You will need to have a basic understanding of plumbing and electrical before attempting this project. There are some steps of this process that are recommended in hiring a plumber (installing a valve to your main water line) and an electrician (if you need to add a power supply for your timer box – outlet box).

install sprinkler valves

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How do you design a sprinkler system?

Planning the layout of your irrigation system is crucial. You need to make sure that you do not overload the number of sprinklers your waterline can handle per valve. 

Your sprinkler design should also give you an idea of the supplies you will need.

Don’t worry – this is not as difficult as it sounds. But if you want someone to design your sprinkler system for you, some sprinkler supply companies offer this service so check around.

To design my sprinkler system, I followed the Hunter “Design and Installation Guide for Residential Sprinkler System.” 

The guide explained precisely how to design a sprinkler system and I highly recommend it. 

Let me walk you through the process.

  1. Create a sketch of the property on a grid paper so that everything is to scale. Draw lawn, trees, flower bed, house, sidewalk, etc. 
    • SIDE NOTE: I broke my yard into sections and used one paper for the backyard, one for the side yard, etc.
  2. Determine the capacity of one sprinkler valve. This is done by checking water pressure, water volume, and water meter size.
    • SIDE NOTE: I could not check my water pressure because all of our outside faucets are actually connected to our house’s pressure, not the main water line that my sprinkler would be connected to. My best estimate for our max GPM (gallons per minute) was 12.
  3. Select the sprinkler heads for the areas. Because I loved the Hunters guide, I chose to use their sprinklers.
  4. Draw the sprinkler head locations. Make sure that each sprinkler is spaced so that it will spray both the head next to it and the head across from it.
  5. Divide the sprinters into different zones based on GPM’s.
  6. Decide on the layout and size of pipes.
  7. Determine where the sprinkler timer will be placed.

This is a quick overview of how to design a sprinkler system. Be sure to look over the Hunter Guide to get more detailed information.

do-it yourself sprinkler design

Now let’s talk about your local code and 811.

CHECK WITH LOCAL AGENCIES

Depending on your area, you may need a permit before installing a sprinkler system.

Also, see if you are required to have a backflow preventer and if so, what type of backflow is allowed.

SIDE NOTE. A backflow preventer prevents contaminated water (sprinkler water) from entering the main water supply (drinking water).

Finally, before you start digging up your lawn, you need to determine where all utility lines are on your property. This can be done by calling 811 (it could be a different number in your state). 

In my state, I can submit a form online; then, within three business days, my property will be marked for free.

Now, back to the process of a sprinkler system installation.

Sprinkler System Installation Supplies

Here are the materials we used. Remember, the actual size and amount of items for your project will depend on your design.


MATERIALS:

TOOLS:

  • trench shovel
  • wood stakes with string
  • PVC pipe cutters
  • wrenches (tighten galvanized pipe)
  • wire cutters
  • wheelbarrow
  • tarp

You can print the material list and instructions below.

Make sure you install the shut-off valve for your sprinkler line first. I would recommend hiring a plumber for this step.

THINGS TO NOTE: In this example, I am connecting to an existing sprinkler system so I don’t have to install a shut-off valve for the main water supply because I already have one.

But to give you an idea of where the sprinkler shut-off value should be placed, there will be a tee from the mainline, then the shutoff valve will be located after the tee.

DIG THE SPRINKLER TRENCHES

SIDE NOTE: A trencher will save you time but you can dig the trenches by hand. Carefully dig by hand around utility markings.

Using wood stakes and string, lay the path where the trenches need to be placed. Consult your design to see where pipes will be installed.

Then, using either a trenching shovel or trencher, dig your trenches on the path you just laid out.

dig trench for spinklers

SIDE NOTE: If we did not have grass, we would have used a trencher.

If you need to dig a trench under a sidewalk, a walkway tunnel kit helps.

CONNECT TO MAINLINE AND INSTALL A BACKFLOW

When the trenches are ready, you can connect to the mainline. 

SIDE NOTE: Use thread seal tape when connecting galvanized pipe together. Also, use PVC cement (glue) and primer with PVC pipes to join pieces together.

After installing the shut-off valve, set up the backflow preventer. In our area, we were allowed to use a pressure vacuum breaker, which works like a backflow but much cheaper.

Municipal code states that our backflow preventer needs to be 12″ above the tallest sprinkler head. Be sure to follow code requirements in your area.

I would recommend using galvanized pipe and fittings for this because PVC will bake in the sun over time, making it crack.

Also, it’s a great idea to use a union on both ends of the preventer so it can be easily removed if needed. I only had a union on one side but later added another so that I can easily winterize the backflow.

install pressure vacuum backflow

INSTALLING SPRINKLER VALVES

Once the backflow preventer is installed, you can run PVC pipe to where the sprinkler valves will be. Use SS (slip x slip) tees to break off from the line.

Remember to use PVC primer and cement (glue).

TIP: Flush the line before installing the valves.

To make the process easier, I used manifolds. These manifolds had pieces like a union so that the sprinkler valve can be unscrewed if it needs to be replaced. The sprinkler company called it an ‘action system’.

install sprinkler valves

SIDE NOTE. There will be a valve box at each of these manifolds.

From the sprinkler valves, you will then connect the PVC pipe to the sprinkler heads.

INSTALL THE SPRINKLERS

Place a stake or flag where every sprinkler head will be placed.

sprinkler head to install

When the PVC pipe reaches a sprinkler placement use an SST (slip x slip x threaded) PVC tee to break off from the line. Cut the PVC pipe at the location.

Attach the 1/2″ barb elbow onto the threaded end of the tee. Then, attach the 1/2″ funny pipe to the elbow. After glue the PVC tee into place.

primer on pvc sprinkler pipe
pvc glue for sprinkler pipe

TIP: Attach the barbed elbow to the tee before gluing into place to make it easier.

install sprinkler fitting

Connect another barb elbow to the bottom of the sprinkler head.

Determine where the funny pipe needs to be cut to connect to the sprinkler. Cut the funny pipe and attach it to the sprinkler head.

TIP: Depending on the type of sprinkler, you may have to flush the line before attaching the sprinkler head. The sprinkler housing that I am using can be flushed after install. But if yours needs to be flushed before, place the funny pipe to the desired location then extend it above ground at least 5″.

Place the sprinkler into the desired location so that the top of the sprinkler is slightly above the ground level.

Pack the soil around the sprinkler housing so that it does not move but do not cover the pipe. You need to check to make sure there are no leaks first.

install sprinkler

Continue adding sprinklers until you only have one left on the line. 

This is where you will add the king drain.

SIDE NOTE: You can add more than one drain per line.

The drain will be added before the last sprinkler by attaching the drain to an SST tee. Then, glue the tee onto the line with the drain facing down.

Now, add the last sprinkler by using an ST 90-degree elbow fitting because the line will end here. Attach the barbed elbow onto the threaded end of the fitting. Then, attach the funny pipe.

Glue the fitting in place and complete the steps to install the sprinkler to the funny pipe.

Continue this process for all sprinkler lines (valves).

If you are using a drip control valve for drip irrigation, see my post on installing a DIY drip irrigation system.

TEST THE SPRINKLER LINES

Once all the sprinkler lines are installed, it’s time to test the lines to make sure there are no leaks.

SIDE NOTE: You can test each line as you finish it.

Please read the instructions for your backflow and sprinkler valves before turning on the water in case there are additional steps needed.

Start by turning on the water at the shut-off valve. Check the lines going to each sprinkler valve., If there are no leaks, move to test a sprinkler valve. 

However, if you do have a leak, turn off the water and fix the leak before continuing.

SIDE NOTE: You usually have leaks because the pipes are not glued.

Test each sprinkler valve by manually turning it on according to the manufacturer’s instructions that came with the valve.

SIDE NOTE: We had issues with our valves not wanting to turn off because the valve had air in it. After letting it sit for a while, the air cleared out and it worked the next day.

Make sure you check every sprinkler line!

INSTALL THE SPRINKLER WIRE

Now that you have tested each water line, it’s time to install the sprinkler wire to automate the sprinklers.

If you are wondering what type of sprinkler wire you need, let’s talk about that. Sprinkler wire is 18-?, the second number being the number of wires. You will need the second number to be the number of sprinkler valves plus 1 for a common.

For example, I have nine sprinkler valves so I will need a wire that is 18/10 (number of sprinklers plus the common wire).

SIDE NOTE: You may need to use two wires to have the number of wires required and if you do, plan on two common wires as well.

Also, this will help you calculate how many stations your timer needs, the minimum amount being the number of sprinkler valves you have.

Now that you know what sprinkler wire you need and timer, let’s install the sprinkler wire.

First, identify where your sprinkler timer will be located. This location can be inside your house, garage, or outside. Wherever you place the timer, you will need access to power.

SIDE NOTE: If you are using a WIFI timer, it needs to be able to receive a wireless signal. Place the timer as close as possible to your internet modem or purchase a modem booster (extender).

The perfect place for our timer was on the exterior of our house, towards the back. I connected power to the area and installed an outlet box since we had none in that area.

install sprinkler timer

TURN OFF THE POWER: To prevent any electrical shock, make sure you turn off the power to the outlet box that the timer is using!

Install your timer according to its instructions. The model we used was straightforward.

To protect the sprinkler wire, we covered it in a  1/2″ conduit PVC pipe. To do this, insert the wire into the pipe and fittings before gluing the pieces together. I would recommend only adding glue to the outside so you do not accidentally glue the wire.

Run the wire from the timer to the closest sprinkler valve (box). Leave at least 12″ of extra wire at the box to allow an easier connection. 

Cut the wire.

Now you need to run the wire to the next sprinkler box but make sure you leave 12″ of extra wire in this box before.

Continue this until you have wire running to each valve location, leaving the extra amount at the next valve box location.

At this time, you can place the valve box over the sprinkler valves. You may need to cut the box to fit around the pipes.

To cut the valve box, place it in the desired location then using a marker, marker where pipes will be so you know what needs to be cut.

Then, using a saw, cut out the marked area. Test the fit and cut again if needed.

cut sprinkler valve box

Now you can wire each sprinkler valve to a wire.

Remember the common wire I mentioned before? This important wire connects all the valves together. And, to be consistent with the standard, use the white wire for the common.

All the other colored wires are for the sprinkler valves, one color for one valve. So for the wire on the sprinkler valve, one will be attached to a color, and the other wire will be shared with the white common.

TIP: Write down the color of wire and what sprinkler zone you plan on using for that valve. Your timer will use zone numbers.

It’s easiest to start connecting the wires at the valve box where the sprinkler wire ends.

Take one wire from each of the sprinkler valves (it doesn’t matter which wire) and the white wire from the sprinkler wire. Connect these wires together using waterproof wire caps.

SIDE NOTE: You will need to remove some of the black jacket from the wire and remove about an inch of the insulation from the wire you plan on using.

Then, wire one sprinkler valve’s remaining wire to a colored wire using a waterproof cap. Wire each sprinkler valve’s remaining wire to a different colored wire the same way.

wire sprinkler valves

TIP: Remember to write down what colors you have used!

Now, move to the next sprinkler box from the last box. You will want to go in the order you placed the sprinkler wire.

But now you have two sprinkler wires in the box. Remove the black jacket from both wires, then the insulation about 1″ from the white wires and the other colors you wired in the last box.

Connect each of the same colored wires together using the waterproof caps (red to red, etc.). You are connecting only the colors you already used and not the white wire yet.

Then, take one wire from each of the sprinkler valves (it doesn’t matter which wire) and take the two white wires from the sprinkler wires. Connect these wires together using waterproof wire caps.

Attach each sprinkler valve’s remaining wire to a different colored wire using the same process. You are only using the sprinkler wire going to the timer, NOT from the last valve box.

Now, move to the next valve box and connect the wires the same way. Connect already used colors, all white wires plus one from each sprinkler valve, then the remaining sprinkler valve wire to a color.

install sprinkler valves

Continue this process until you are at your timer. 

Then, wire the timer, placing the white wire in the common and each color wire used in a zone. Remember, your sprinkler design will have this all laid out for you.

wiring Orbit sprinkler timer

BURY THE PIPE AND WIRE

After you have finished wiring, you can bury the PVC pipe and wire with the dirt you removed earlier.

TIP: Make sure the dirt gets compacted around the pipe.

If you happened to have grass before starting this project, replace the grass. 

If not, now would be a great time to plant some because you have sprinklers.

replace grass after installing sprinkler system

I hope this will make it easier for you to do your own sprinkler system installation.  With a little planning and time, you can have an automatic sprinkler system and finally put away the old garden hose!

sprinkler system installation for lawn

Interested in more landscaping projects? Here are some other posts you might enjoy:

Yield: sprinkler system

Install Automatic Sprinkler System

lay sprinkler pipe

The process of installing an automatic sprinkler system for a yard. See what supplies and steps to DIY a sprinkler system.

Prep Time 30 minutes
Active Time 15 hours
Additional Time 1 hour
Total Time 16 hours 30 minutes
Difficulty Moderate

Materials

  • sprinkler timer, I am loving the WiFi one
  • sprinkler valves
  • backflow preventer
  • PVC pipe
  • sprinklers
  • manifolds
  • valve box
  • flexible swing pipe (also known as a funny pipe)
  • king drains
  • sprinkler wire
  • galvanized pipe for backflow
  • 1/2" elbow spiral barb
  • PVC 90-degree Elbows Slip x Slip (lots)
  • PVC tees Slip x Slip (lots)
  • PVC 45-degree elbow Slip x Slip (lots)
  • size of PVC pipe"x 1/2" PVC 90-degree reducing elbows Slip x FPT (end sprinklers)
  • size of PVC pipe" x size of PVC pipe"x1/2" PVC reducing Tee Slip x FPT (connect the sprinkler to pipe)
  • action manifold parts
  • PVC Primer and glue
  • waterproof wire nuts
  • pipe thread tape
  • 1/2" conduit pipe with fittings (optional for wire)

Tools

  • trench shovel
  • wood stakes with string
  • PVC pipe cutters
  • wrenches (tighten galvanized pipe)
  • wire cutters
  • wheelbarrow
  • tarp

Instructions

  1. Design your spinkler system or have a local sprinkler company design it.
  2. Check with local agencies to determine where utility lines are on the property.
  3. Dig the trenches for the sprinkler lines.
  4. Connect to the main water line and install shutoff valve for sprinkler line.
  5. Install a backflow preventer.
  6. Run pipe to sprinkler valves and install the valves.
  7. Continue the pipe from the valve to each sprinkler location then install sprinkler head (or leave only flexible pipe). Compelete this step for each valve and sprinkler.
  8. Test sprinkler lines for leaks and to flush the line. If no, leaks install sprinkler heads.
  9. Install sprinkler timer at desired location then install the sprinkler wire.
  10. Bury the sprinkler pipe and wire.
  11. Setup your automatic timer and enjoy your sprinkler system.