Calculadora de Captación de Agua de Lluvia — Fórmula
## How to Calculate Rainwater Collection
Rainwater harvesting captures roof runoff for irrigation, toilet flushing, or other non-potable uses.
### Formula
**Gallons = Roof Area (sq ft) * Rainfall (inches) * 0.623 * Collection Efficiency**
The factor 0.623 converts 1 inch of rain on 1 sq ft to gallons. Efficiency accounts for gutter losses, first-flush diversion, and evaporation.
Rainwater harvesting captures roof runoff for irrigation, toilet flushing, or other non-potable uses.
### Formula
**Gallons = Roof Area (sq ft) * Rainfall (inches) * 0.623 * Collection Efficiency**
The factor 0.623 converts 1 inch of rain on 1 sq ft to gallons. Efficiency accounts for gutter losses, first-flush diversion, and evaporation.
Ejemplo Resuelto
1,500 sq ft roof in an area with 40 inches annual rainfall, 80% collection efficiency, $5/1000 gal water cost.
- Annual collection: 1,500 * 40 * 0.623 * 0.80 = 29,904 gallons
- Monthly average: 29,904 / 12 = 2,492 gallons
- Annual savings: 29,904 * $5 / 1,000 = $150
- Recommended tank: ceil(2,492 / 100) * 100 = 2,500 gallons