Category Planning & Sizing

Calculate roof rainwater yield from catchment area and rainfall, then reduce the total for surface runoff, first flush, gutter loss, and tank overflow.

Asphalt-shingle roofs can supply rainwater for selected uses; learn how roof age, debris, granules, treatment, and testing influence appropriate use.

Compare roofing materials for rainwater harvesting by runoff quality, coatings, texture, debris retention, maintenance, durability, and intended water use.

Calculate household water demand by totaling fixture, appliance, irrigation, and leak use over time, then distinguish average consumption from peak flow.