DIY Rooftop Rainwater Catchment System¶

Rainwater & Storage • Est. CapEx: Low-cost / Locally fabricated

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	Low-cost / Locally fabricated
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.
Target Scale	Household / Village Cluster
Standard Lifespan	10 - 20 Years

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.