Sprinkler Head Spacing 101

I can drive through any neighborhood and tell you which sprinkler systems were designed properly just by looking at the lawn. The secret? Head-to-head spacing. Every single time.

The Golden Rule

Every sprinkler head should throw water far enough to reach the next head. This is called head-to-head coverage, and it's non-negotiable. If your heads are spaced 30 feet apart, each head needs to throw at least 30 feet.

How to Calculate Spacing

1. Check your nozzle's throw distance. This is on the manufacturer's spec sheet. For example, a Rain Bird 5000 with a #3 nozzle throws about 35 feet at 45 PSI.
2. Reduce by 10%. Real-world conditions (wind, pressure loss) mean you should design at about 90% of rated distance.
3. That's your maximum spacing. If the adjusted throw is 31.5 feet, your heads go no more than 31.5 feet apart.

Common Spacing Patterns

• Square spacing: Heads in a grid pattern. Good for rectangular areas. Space = throw distance.
• Triangular spacing: Heads offset in alternating rows. Gives you about 15% more coverage efficiency. Space = throw distance.
• Perimeter spacing: Heads along edges, throwing inward. Great for narrow strips and borders.

The Biggest Mistake I See

Homeowners trying to save money by spacing heads farther apart. You end up with dry spots, brown patches, and an ugly lawn. You'll spend more on water trying to compensate than you saved on the extra head. Trust me — I've been fixing this mistake for decades.

Mixed Head Types

Never mix rotors and spray heads on the same zone. They have completely different precipitation rates. Spray heads put down water at about 1.5 inches per hour. Rotors put down about 0.5 inches per hour. Mix them, and your spray areas will be swamps while your rotor areas are deserts.