Building an automatic irrigation system is an investment that pays for itself in the first season. Instead of daily hand-watering you get uniform coverage, water savings, and a healthy lawn without effort. This guide covers every stage in detail: from measuring your site to the first startup.
1. Survey your property
Grab a tape measure (or use a GPS app on your phone) and record every dimension of your yard. Note them on paper or enter them directly into SmartPluvia. For a paper plan, a scale of 1:100 (1 cm = 1 m) works best.
Mark the following on your plan:
- House, garage, sheds — these must not be irrigated
- Walkways, patios, driveways — no-water zones
- Trees and large shrubs — they block sprinkler coverage
- Flower beds and borders — need separate irrigation (drip or micro-spray)
- Lawn areas — the main sprinkler zone
2. Determine your water supply
Find your point of connection (POC) — usually an outdoor spigot or meter. You need two key numbers:
- Static pressure — screw a pressure gauge onto an outdoor faucet (with all other fixtures closed) and read the value. Normal range: 2–4 bar (30–60 PSI)
- Flow rate — open the faucet fully and fill a bucket of known volume. Example: a 10-liter bucket in 30 seconds = 20 L/min (5.3 GPM). Typical municipal supply: 15–30 L/min (4–8 GPM)
These two numbers determine how many sprinklers can run at once and which nozzle types will work.
3. Design irrigation zones
Zones exist because your water source cannot power all sprinkler heads simultaneously. The controller activates zones one at a time.
The 80 % rule: total nozzle flow in a zone must not exceed 80 % of source capacity. If your tap delivers 25 L/min — each zone maxes out at 20 L/min.
Sample zone breakdown (200 m² yard)
- Zone 1 (front lawn, 60 m²): 4 fixed-spray nozzles × 4 L/min = 16 L/min
- Zone 2 (side lawn, 80 m²): 3 MP Rotators × 5 L/min = 15 L/min
- Zone 3 (backyard, 60 m²): 4 fixed-spray nozzles × 4 L/min = 16 L/min
Never mix fixed-spray nozzles (40 mm/h) with rotors (12 mm/h) in the same zone — mismatched precipitation rates cause dry spots and puddles. See also our step-by-step tutorial.
4. Choose your equipment
Key components:
- Nozzles (sprinklers) — rotors, fixed spray, or MP Rotator. Under 5 m (16 ft) throw → fixed spray; 5–10 m (16–33 ft) → MP Rotator; over 10 m (33 ft) → rotors
- Solenoid valves — one per zone. A 1" (25 mm) valve covers most residential zones
- Controller — basic timer or WiFi-enabled (Hunter HC, Rain Bird ESP-TM2). WiFi lets you adjust schedules from your phone and integrate a rain sensor
- Pipes — 32 mm (1¼") mainline from supply to valve box, 25 mm (1") laterals from valves to heads
- Fittings — elbows, tees, couplings. Use compression fittings for PE pipe — no gluing or welding required
- Sensors — rain sensor (essential!), soil moisture sensor (optional)
- Drip irrigation — for beds and borders: Netafim UniRam pressure-compensating drip tape or budget 16 mm tubing; for connections use Generic PE/PVC fittings
5. Installation
Step-by-step:
- Mark pipe runs on the ground (use marking paint or stakes with string)
- Dig trenches 25–30 cm (10–12") deep
- Lay the mainline (32 mm) and lateral pipes (25 mm)
- Mount sprinkler heads on swing joints — these let you fine-tune height and position after backfill
- Install the valve box and solenoid valves
- Wire the controller and run control cable to the valves
- Test every zone before backfilling! Turn on the water, inspect all connections for leaks, confirm heads pop up and rotate correctly
- Backfill trenches and restore the lawn
6. Startup and adjustment
Flush each zone for 2–3 minutes. Adjust the radius and arc of every head with the provided key. Set the schedule — early morning (5:00–7:00 AM) is best because evaporation is lowest.
Cost estimate
For a 200–500 m² (2,200–5,400 sq ft) property: $250–$650 covering nozzles, valves, controller, pipes, and fittings.
Start your design in the free SmartPluvia planner — draw your boundary, place sprinklers, and get an automatic parts list in minutes.