DIY Rooftop Rainwater Catchment System¶

Rainwater & Storage • Est. CapEx: $200 USD • Lifespan: 7–15 Years

Technical Overview¶

A comprehensive, open-source guide for designing and building low-cost rooftop rainwater harvesting systems for domestic use, including non-potable applications like irrigation and toilet flushing. Perfect for practitioners, DIYers, and communities in water-scarce regions.

Key Specifications & Engineering Parameters¶

Parameter	Specification
Category	Rainwater & Storage
Capital Cost (CapEx)	$200 USD
Power / Energy	100% Gravity / Zero Power
Target Scale	Household (5–10 people)
Standard Lifespan	7–15 Years
Technology Maturity	Commercially Available
Primary Mechanism	Rainwater is captured from rooftops via gutters and downspouts, screened to remove debris, directed through a first-flush diverter that discards the initial dirty runoff, and stored in a cistern or tank. Water can be used by gravity flow or pumped, and optionally treated for potable use.

Engineering Trade-Offs¶

✅ Advantages⚠️ Limitations

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Cross-Reference & Interactive Tools¶

Need to evaluate this technology for your specific field site? Run the WhatWater.info Selector Engine to compare it against 100+ alternative solutions.