The process is to take the rainwater from the roof, down your down pipe and into a storage tank. Whilst the water is traveling from your rooftop it must pass via a filtration system, either built in to the down pipes or better still built into the underground tank.

You then have clean fresh water stored in the underground tank. Please note you do not take the water from the ground i.e driveways or patios due to potentially causing contamination in the water. Also it is not advised especially if you are using the water in the house to collect water that has come from a ‘Green Roof’.

This rainwater can then be used for either toilet flushing, washing machine and anything external like irrigating the garden or washing the car. The rainwater is pumped to the appliances via a pump either directly or via a gravity feed system, we will come to that shortly.

All Rainwater Harvesting Systems should have an overflow device so when your tank fills up and excess water or debris, leaves etc get discharged through the overflow device to a soakaway, watercourse or drainage system.