Rainwater and greywater use in buildings. Best practice guidance

The government, water regulators and water supply undertakers are all encouraging the adoption of water conservation measures. One component of these measures is to use rainwater and greywater (ie water from wash basins, baths, and showers) as a source of water to reduce the reliance upon the mains water supply. There has been relatively little guidance on how separate or combined rainwater and greywater systems may provide safe water to buildings. The guidance provided here is based on the findings from demonstration sites, consultation with stakeholders and contact with other sites not directly monitored by the project. It gives further detail and specific recommendations for rainwater and greywater use. The guidance is aimed at developers, building owners, equipment manufacturers and their consultants and contractors. It will also be of interest to water utilities, local authorities, environmental regulators and house builders wishing for further detail than that provided in the companion volume.