Over years of work, we've seen hundreds of irrigation projects. Here are five of the most common mistakes made by beginners and experienced installers alike.
Mistake 1: Insufficient head-to-head coverage
The most common mistake — placing sprinklers too far apart. Result: dry spots on the lawn.
Correct approach: distance between sprinklers should equal the throw radius (head-to-head rule). If a nozzle has a 5 m radius, space sprinklers 5 m apart, not 10 m.
Mistake 2: Mixing nozzle types in one zone
Fixed spray nozzles deliver 40-50 mm/hr, while MP Rotators deliver 10 mm/hr. Mixing them in one zone means one area gets flooded while another stays dry.
Correct approach: use only one nozzle type per zone with matched precipitation rate.
Mistake 3: Ignoring hydraulics
Too many sprinklers on one zone = pressure drop = nozzles won't reach full radius.
Correct approach: always calculate total zone flow and compare with source capacity. Keep a 25% reserve.
Mistake 4: No check valves on slopes
On sloped areas, water drains through the lowest sprinklers after the zone shuts off (low-head drainage), causing oversaturation.
Correct approach: use sprinkler bodies with built-in check valves at low points.
Mistake 5: Undersized pipes
Too narrow a pipe creates high flow velocity, leading to water hammer and noise.
Correct approach: pipe velocity — max 1.5 m/s (5 ft/s). Mainline — min 32 mm (1.25"), laterals — min 25 mm (1").
How to avoid all these mistakes
Use our planner that automatically checks overlap, hydraulics, and equipment compatibility.