Sprinkler Head Spacing Calculator

Overview

Compares planned spacing to nozzle throw radius and lays out an approximate square or triangular head count over a bounding rectangle.

Assumptions

• This calculator uses spacing equal to radius as its head-to-head planning assumption; it is not a universal design rule.
• Irregular shapes receive a 15% planning bump.

Worked example

A 50 × 30 ft rectangle with 25-ft radius uses 3 columns and 2 rows, or 6 heads; planned 30-ft spacing is 30 ÷ 25 = 1.2× radius.

Common mistakes

• Using radius as diameter.
• Mixing different precipitation-rate heads in one zone.

Limitations

Obstructions, wind, pressure, nozzle arc, and exact boundary layout are not modeled.

Safety and local requirements

Confirm local backflow and watering requirements before installation.

Sources

• EPA WaterSense — irrigation efficiency background