Rainwater harvesting
Roof area × rainfall → liters per year; tank size and savings
Parameters
Liters per year
Recommended tank: ≈1 300 л
66 960 л
Covers watering: ~3 348 м² seasonal watering
1 mm rain × 1 m² roof = 1 liter. Runoff: tile/metal 0.9, gravel 0.7. Rainwater is for irrigation, flushing, laundry (filtered); not potable untreated.