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Commercial Irrigation System Installation and Maintenance Tips


Improve your property’s image, reduce water waste and reduce costs with help from The Home Depot. Our commercial irrigation system installation and maintenance tips are designed with your business in mind. Whether you are replacing parts, expanding an existing system or installing a new irrigation system, we have you covered.


How to Determine Water Capacity

Follow these 5 simple steps to calculate your system’s water capacity. Once you know your system’s water capacity, use it to make crucial irrigation decisions like choosing the right sprinkler heads and determining zone size.

  1. Turn off all faucets and water sources so you can accurately measure water capacity.
  2. Attach a pressure gauge to an outside faucet, turn it on until the gauge reads 35 psi and leave it running.
  3. Locate the outside faucet closest to your property’s main water source, and turn it all the way on.
  4. Place a 5-gallon bucket underneath the faucet, and time how long it takes to fill. Turn the water off once the bucket is filled.
  5. Determine water capacity in gallons per minute (GPM) based on how long it took to fill the bucket using this chart.
  • 5 seconds = 60 GPM 
  • 10 seconds = 30 GPM 
  • 15 seconds = 20 GPM 
  • 20 seconds = 15 GPM 
  • 25 seconds = 12 GPM
  • 30 seconds = 10 GPM 
  • 35 seconds = 8.57 GPM 
  • 40 seconds = 7.5 GPM 
  • 45 seconds = 6.67 GPM 
  • 50 seconds = 6 GPM


Get the most out of your irrigation system with the proper piping. Different piping materials perform better under certain conditions. All pipes have a maximum GPM rating that should be followed for the safest, most efficient performance.




Galvanized steel pipe withstands extreme pressures. It is commonly used for water supply lines and some irrigation applications.

  • 3/4"
  • 1"
  • 8 GPM
  • 13 GPM

Polyethylene pipe, also known as alkathene, is used for cold water and irrigation. Its psi ratings vary.

  • 3/4"
  • 1"
  • 8 GPM
  • 13 GPM
PVC Schedule 40

Polyvinyl chloride Schedule 40 pipe is used for pressurized irrigation and rated for 200 psi.

  • 3/4"
  • 1"
  • 8 GPM
  • 13 GPM
PVC Class 200

Polyvinyl chloride class 200 pipe is the new standard for pressurized irrigation and rated for 450 psi.

  • 3/4"
  • 1"
  • 10 GPM
  • 15 GPM
Type K Copper

Copper tubing is used for water supply lines and heated water applications. It is not commonly used for direct irrigation.

  • 3/4"
  • 1"
  • 6 GPM
  • 12 GPM

Installation, Watering & Winterization Tips


  • Plants and flowers need more water than grass. 
  • Grass needs more water than trees and shrubs. 
  • Run your system early in the morning to avoid overwatering. 
  • Consider drip irrigation for trees, shrubs and areas that lack grass.                      


  • Learn which areas need more water than others before installing or upgrading your system. 
  • Install irrigation pipes 8" to 12" deep to help avoid accidental damage. 
  • Call your utility company and have them mark where pipes and power lines are before digging.


  • Insulate all aboveground pipes, valves and backflow preventers to prevent cold damage.
  • Check air vents and drain outlets and clear any blockages.
  • Blow air through your irrigation system to remove excess water and protect against freezing.
  • Deactivate timers and controls so your system's valves and pumps cannot activate. 

Irrigation System Parts & Supplies

Pipes, Fittings & Valves

Water capacity, zone or sprinkler head count and the size of your lawn determine how much pipe you need and how many valves you will have to use.

Sprinkler Heads

Use different sizes of sprinkler heads in different zones for more efficient watering. More appropriate spray patterns can also help reduce irrigation costs.

Timers, Controls & Moisture Sensors

Take control of irrigation costs with sprinkler timers and digital controllers. Advanced models can be used remotely and can be set by zone area.

Tools & Other Irrigation Essentials

Get the job done right the first time, every time, with commercial-grade irrigation tools and supplies from The Home Depot.