Sprinklers System Install Examples

System Layout Example
Sprinkler system layout example plans
  1. Residence
  2. Main Line
  3. Zone 1
  4. Zone 2
  5. Zone 3
  6. Stop and Waste
  7. Backflow Preventer
  8. Automatic Sprinkler Valves
  9. Pop-up Spray Sprinkler Head
  10. Rotor Sprinkler Head
  11. Drip Connection or Bubbler
  12. Wiring for Irrigation Valves
  13. Irrigation/Sprinkler Timer

This is an example of what the layout of a front yard sprinkler system may be like. The laterals are color coded to avoid confusion.

Sprinkler Head Layout

Sprinkler head layout is perhaps the most important part of your personal installation. If you don't have a proper layout, you won't have good performance and will likely waste thousands of gallons of water each season.

Head to Head Coverage

Head to head coverage is a term you will often hear when having a conversation about sprinklers. In head to head coverage, every spot in the irrigated / watered area needs to be covered by at least 2 sprinkler heads, and each head should throw water far enough that it reaches or slightly overlaps the adjacent heads. This is done by considering each sprinkler as a geometric shape. Each sprinkler head is rated with an ARC and Radius, this provides you with the shape you will use to determine coverage. The geometric shapes will all be based around a circle, while your layout will be based around a square or triangle pattern. This is where inefficiency comes in to play, because you are trying to fit a round object into a square or triangle pattern.

Layout Examples
sprinkler Coverage Layout Example

The shapes in the pictures are representing the space between sprinkler heads

sprinkler Coverage square pattern Layout Example

Each sprinkler head used in these examples are full heads to help demonstrate how important layout can be.

sprinkler coverage triangle pattern Layout Example

As you can see, the triangle pattern (actually called a diamond pattern) is more efficient, but it is less common because it is more difficult to lay out. Most residential sprinkler systems are done using the square pattern.

Layout can actually be quite simple. I generally walk around a property with a measuring tape or wheel and place flags according to available products based on distance. Example, starting with a corner, I measure one side or edge of the area to be irrigated, and determine what type and size of sprinkler head will fit best. I then repeat this for every side / edge of the irrigated property until I get an adequate layout to provide good coverage. I then transfer the layout to paper or my computer to see if I have missed anything obvious. I generally pull the property up on Google Earth or Google Maps and take a screen shot, then I use a simple drawing app to apply my layout. There is software that can aid you in setting up your layout, but it is expensive, and it takes time to learn how to use it.

Measuring the property for spacing of Sprinklers

Measure the property for spacing of Sprinklers

layout plans using sprinkler heads

Create a layout using sprinkler heads; use rotors for larger areas if possible.

sprinkler system layout plan example

This is an example of an actual sprinkler system layout.

sprinkler system layout and coverage example

As you can clearly see, the layout is good, but there are still gaps in overlapping coverage. This is a common problem, but it is unavoidable.

sprinkler system layout and coverage example

As you can clearly see, the layout is good, but there are still gaps in overlapping coverage. This is a common problem, but it is unavoidable.

Stop and Waste
Stop and Waste Example schematic

This is a must in areas that have hard freezes. The stop and waste is a shutoff valve that drains the downstream water from a main line. It is generally installed at the point of connection that is leading to the sprinkler system (generally close to the meter or a building). The weep hole allows water to escape when the valve is closed. Thus, a stop and waste is regularly installed at a depth that is sufficient to prevent freezing of the live side of the water main.

Stop and Waste
Backflow Preventers

A backflow is required for any sprinkler system supplied from culinary water (drinking water). If you are not familiar with Backflows you need to do some research for your particular area since there are different requirements for different areas.

Backflow Definition

Undesirable reversal of flow of a liquid, gas, or suspended solid into the potable water supply. A backflow preventer is designed to keep this from happening.

Why Do I Need A Backflow Protection Device?

A Backflow Preventer protects drinking water from becoming contaminated in the event of a loss in pressure from the supply.

Backflow Preventers Commonly Installed on Sprinkler Systems

PVB, Pressure Vacuum Breaker

Backflow Preventer PVB schematic, Pressure Vacuum Breaker

The PVB is my favorite backflow preventer to use. It is easy to install, meets the requirements for most sprinkler systems and water departments, and it is also the least expensive. As long as you follow the installation guidelines/instructions provided by the manufacturer, this backflow preventer provides a great line of defense. The only form of backflow that the PVB does not protect against is back pressure. It is never a good idea to use a PVB in a system that has any kind of pump or has any kind of secondary water supply.

RP, Reduced Pressure Assembly

Backflow Preventer RP schematic, Reduced Preventer Assembly

The RP is the best protection available for sprinkler systems connected directly to a pressurized culinary / potable water system. The RP backflow preventer is also the most expensive option in most cases.

To Learn More Check Out This You tube Video "What is Backflow"

Measuring Water Supply
Measuring Water Supply for GPM

The most common method is to measure the amount of water supplied from a hose bib on the property. Simply place a 5-gallon bucket, such that it will catch all the water from the hose bib, while it is running. Turn the hose bib fully on and measure the time it takes to fill the bucket to overflowing.

  • The figures below will help you determine your GPM using the bucket method.
    • 60 seconds = 5 GPM
    • 50 seconds = 6 GPM
    • 42 seconds = 7 GPM
    • 37 seconds = 8 GPM
    • 33 seconds = 9 GPM
    • 30 seconds = 10 GPM
    • 27 seconds = 11 GPM
    • 25 seconds = 12 GPM
    • 23 seconds = 13 GPM
    • 21 seconds = 14 GPM
    • 20 seconds = 15 GPM

Keep in mind that if you are taking the GPM measurement from the house your reading is unlikely to be accurate. It will certainly give you a good base line, but it will likely be lower than the actual available GPM.

If the flow rate falls below your desired GPM, it is best to measure the GPM again after installing the stop and waste. In this case you will want to use the newly installed connection rather than a hose bib. Simply pipe the water to your bucket, turn on the stop and waste and time how long it takes to fill your 5-gallon bucket. To perform this test the fittings and pipe you use to reach your bucket will most likely not need to be glued, as they are not carrying water under static pressure, and it is a temporary solution being used to measure flow.

Your target rate of flow should be close to the maximum GPM or feet per second for your property main line.

  • Target max GPM based on pipe size. This differs depending on the material that your main line is made of; this is simply a rule of thumb.
    • 5 GPM for 1/2" pipe
    • 9 GPM for 3/4" pipe
    • 15 GPM for 1" pipe
Garden Spigot / Hose Bib
Sprinkler Hose bib schematic

Hose bib schematic

Garden Spigot running

Garden Spigots are a great source for large volumes of water to be supplied with a garden hose. They tend to have more volume and pressure than a regular garden spigot. The most common use is for filling a pool or hot tub quickly.

Trenching, Digging or excavating

Warning! Always have utilities located before digging. In the U.S., call 811 or go to https://www.bluestakes.org/, Which is a free service.

Trenching, Digging or excavating, trench that has been dug with a machine
How Deep Do I Go?

This is a question I hear all the time. How deep do I go? Meaning, how deep should a sprinkler system piping be buried? If your system is designed to drain when not under pressure, you likely don’t need to place the lines very deep at all. A good rule to follow when considering the depth of a sprinkler system is, measure the body of your most commonly used sprinkler heads, then add 2 inches. For example, if you are using Rain Bird 1804 pop-up sprinkler heads, the body is 6”, so I would recommend that the sprinkler piping be 8 inches deep in this case. I never go deeper than 12 inches for residential properties. If you go deeper than that you are more likely to run into problems with utilities. After connecting to the stop and waste, I will bring the irrigation supply main line up to this depth before running the remaining irrigation main line for the system.

Teflon and Pipe Dope
Teflon tape

I typically only use these sealants on threaded fittings for charged lines (main lines) and immediately following the valves. I generally don’t use Teflon for lateral lines since they are unlikely to leak much while running and this gives a place for water to escape for winterizing. In exception, I use Teflon on all above ground threaded fittings and fittings that are tight or fittings that don’t thread well (PVC to PVC often have this problem, which is why I recommend using Marlex fittings for swing joints).

Sprinkler Valves Manifold Assembly Example

This particular setup has 3 valves (one drip valve kit and 2 DVF valves, a gate valve to shut this valve bank down for minor repairs and a ball valve used as a winter drain.

Sprinkler Valve Manifold schematic

Manifold schematic

All Fittings are PVC

  1. 1 Inch Tee Slip x Thread
  2. 1 Inch Close Nipple
  3. 1 Inch Union Threaded
  4. 1 Inch Close Nipple
  5. 1 Inch Valve DVF
  6. 1 Inch Toe Nipple
  7. 1 Inch Union Slip
  8. Optional Drip Filter
  9. Optional Hose Bib/Ball Valve (Used for Winterization)

My preferred Manifold setups are 2-4 DVF valves, my preferred way to assemble the threaded components is to wrap the threads 3 times with Teflon tape. In addition, I also apply a small amount of thread sealant to the fittings on the main line side of the valves. Do not over tighten, if you use both Teflon tape and Thread sealant, hand tight should be sufficient.

Valve Wiring
Sprinkler Valve Wiring Example

Valve wiring can be simple, but it can also cause problems if not done properly. When wiring valves, use an approved wire designed for sprinkler systems. If you take a closer look at the wire, each strand is color coded to make installation easier. When wiring valves, you need to choose a color to use as your common. The common is generally the white wire, but I have depicted it as Blue in the wiring image, just to make it stand out. As you can see, the common connects to each valve, along with a different color of wire run to each separate valve. When I wire valves, I always start by selecting one wire from each valve and connecting them to the common (there are 2 wires coming out of each valve solenoid, as these wires are connected to a coil / electromagnet, the polarity doesn't matter, so simply select a wire for the common and the other will be used to control the valve). Once you have the common connected, you will have one wire left for each valve. Simply connect a different color wire to each valve. The color doesn't matter, but I always stick to a color code to make it easier when installing the clock / sprinkler timer.

My color code for wiring, just as a reference. Your wire may be different colors.

  1. Red
  2. Yellow
  3. Blue
  4. Green
  5. Orange
  6. Purple
  7. Gray
  8. Black
  9. Pink
Sprinkler Zone Layout and Laterals
Sprinkler Zone Layout schematic
  1. 3/4" PVC pipe Schedule 40
  2. 3/4" Slip PVC Tee
  3. 3/4" Slip x 1/2" Thread PVC Elbow
  4. Barbed swing pipe Fitting for Swing Joint Attachment
Sprinkler Zone Layout Example schematic

Sprinkler Zone Layout Example

  1. Laterals for Separate Zones
  2. 1" PVC Pipe Schedule 40
  3. 1" Slip Tee
  4. 3/4" PVC Pipe Schedule 40
  5. 1" x 3/4" Slip Reducer Bushing

Sprinkler Zone Layout Explained

In this sprinkler zone layout example the pipe size remains 1 inch until the second Tee. After this Tee, the piping and fittings remain 3/4 inch up to the Funny Pipe connections. It is a good practice for the pipe size to remain 1 inch (if the available water is 9-16 GPM) until the first Tee, or until the zone has supplied 1/3 of the sprinkler heads. In this example we will assume that the sprinkler heads are 1804's with Rain Bird 15 nozzles. In that case this zone would be using 13.86 GPM, this rate of flow is too high for a 3/4" line to supply. Your objective is not to exceed 5 feet per second. It would be ideal to calculate the flow at each point in a system, but that is not realistic in most cases. Instead, I reduce the pipe size after I have installed 1 Tee that diverts the water relatively equally, or after I have installed the fittings that supply 1/3 of the sprinkler heads.

1/2" PVC

You may have noticed that I have not included 1/2" PVC. I never install 1/2" PVC, I run 3/4" to the last PVC fitting and at that point I use Funny Pipe. I find that this method saves a ton of time and has no adverse effects on the performance.

Swing Joints and Sprinkler Heads
Sprinkle Swing Joint PVC parts

Swing joints are a flexible way to install sprinkler heads. The swing pipe length can be anywhere from 3 inches on up. There isn’t really any limit to the distance of the swing pipe as long you don’t exceed the velocity of the pipe, especially for long runs (I often use swing pipe as laterals for supplying individual sprinkler heads.). The maximum recommended flow for swing pipe / Funny pipe is 3 GPM, but you can exceed this rating for short distances. For sprinkler heads that exceed this velocity, I recommend having a swing joint that is no longer than 18 inches.

Pop-up Swing Joint schematic

Pop-up with Swing Joint

  1. Pop-up Sprinkler Head
  2. 1/2" Marlex coupled with 1/2" Funny Elbow
  3. Funny Pipe
  4. 3/4" Slip x 1/2" Thread PVC Tee coupled with 1/2" Funny Elbow
  5. 3/4" PVC pipe Schedule 40
  6. Optional 3/4" Slip x 1/2" Thread PVC Elbow
  7. Optional 1/2" Auto Drain (Generally only 1 installed at the lowest point of each zone)
Rotor Swing Joint schematic

Rotor with Swing Joint

  1. Rotor Sprinkler Head
  2. 3/4" Marlex coupled with 3/4" Funny Elbow
  3. Funny Pipe
  4. 3/4" Slip x 1/2" Thread PVC Tee coupled with 3/4" Funny Elbow
  5. 3/4" PVC pipe Schedule 40
  6. Optional 3/4" Slip x 1/2" Thread PVC Elbow
  7. Optional 1/2" Auto Drain (Generally only 1 installed at the lowest point of each zone)