Zone count from your water supply's GPM, sprinkler heads, pipe, wire and valves.
Estimates are planning aids, not a professional quote. Double-check quantities and product coverage — and any local code or permit requirements — before you buy.
| Drainage | $706–$955 |
| Total | $706–$954 |
Excludes tools, delivery, tax and permit fees. Labor not included — this is a DIY materials estimate.
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About this calculator
The Sprinkler System Builder sizes an in-ground irrigation system the way an installer actually does — from the water supply down, not just the yard's square footage. Enter your area and the flow rate available at the spigot or meter, and it works out how many spray or rotor heads the coverage needs, then splits them into the fewest zones your GPM can run without starving the heads at the far end of the line. That zone count is what drives everything downstream: pipe, wire, valves and the controller size.
Choose spray or rotor heads and the spacing, per-head flow and price all adjust, since rotors throw farther on fewer heads but need more GPM each to do it. Advanced options dial in static pressure, pipe material, the wire run to your farthest valve, and backflow device type, because your actual water pressure and local plumbing code change what the system needs more than the yard's shape does. This plans materials and layout only — it isn't a substitute for a licensed backflow inspection where your area requires one.
Step by step
A step-by-step walkthrough to go with your plan above. Follow the product instructions and any local code or permit requirements as you work.
Measure actual GPM with a bucket and stopwatch and static pressure with a spigot gauge, then use those numbers here — not the utility's nameplate figures — to get a zone count you can trust.
Mark head locations on the spacing your head type needs, group them into zones that stay under your available GPM, and route the mainline path from the water source to a central valve manifold location.
Tie the backflow preventer into the supply line above ground per local code, then trench and run pressurized mainline pipe from there to the valve manifold location.
Dig zone trenches to your local frost-safe depth, lay lateral pipe from each valve out to its heads, and dry-fit before gluing or crimping any PVC joints.
Install swing pipe or riser assemblies at each head location, set pop-up bodies flush with finished grade, and cap or plug the far end of each lateral run until flushing.
Run control wire from each valve back to the controller location, land one wire per zone plus a shared common, and test continuity on every run before backfilling any trench.
Open each zone before capping the last head to flush debris out of the lines, then cap it, run each zone, and adjust arcs and radius so coverage overlaps head-to-head without spraying pavement.
Backfill trenches and tamp them down, then program the controller with run times per zone and, if installed, wire in the rain or freeze sensor so it skips cycles after real rainfall.
Equip the job
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Keep planning
Garden & Yard
Answers
Zone count comes from a hydraulic limit, not just yard size: however many heads your available GPM can run at once, divided into your total head count. A big yard on strong municipal pressure might only need three or four zones, while the same size yard on a weak well supply could need eight or more, because each zone can only hold as many heads as the flow allows before pressure drops too far to spray evenly. Get an actual flow reading at the spigot before finalizing a design — nameplate GPM from your utility is often optimistic.
Time how long it takes to fill a 5-gallon bucket from an outdoor spigot at full open, wide open valve — divide 5 by the seconds and multiply by 60 to get GPM. For static pressure, a $10 gauge that threads onto the same spigot gives a direct psi reading. Do both with no other water running in the house, since a dishwasher or shower cycling at the same time will undercut both numbers and make your zone count look smaller than it really is.
Spray heads throw a fixed fan pattern about 15 feet and suit smaller, more detailed areas — narrow strips, beds, small lawns — because they're cheap and easy to adjust. Rotor heads throw a rotating stream 25 to 35 feet and use less water per square foot covered, which makes them the better fit for open lawn areas over a few thousand square feet, at the cost of a higher per-head flow requirement and a higher unit price. Most residential yards end up needing both on separate zones, though this calculator prices one head type per run.
In most jurisdictions, yes — any irrigation system plumbed into potable water needs a device that stops fertilizer- or chemical-tainted water from siphoning back into the house supply if pressure drops. A pressure vacuum breaker (PVB) is the common, cheaper choice for a straightforward above-grade system; a reduced-pressure zone (RPZ) device is required in more areas and where any chemical injection is possible, and typically needs annual certified testing. Check with your local water utility before buying — this is set by local code, not by the system's design.
Most residential irrigation runs 6 to 12 inches deep, shallower than a water main since the system gets drained or blown out before freezing weather rather than staying pressurized all winter. Check your local code for a minimum, and go deeper under driveways or anywhere heavy equipment might cross. In any climate that sees hard freezes, plan on blowing the lines out with compressed air every fall — that's what protects buried pipe and fittings, not depth alone.