A greywater solution for a block of 136 flats

PTEa and Galliford Try developers commissioned ech₂o to carry out a feasibility study for greywater recycling in a refurbishment project for 136 flats in North London to meet the planning requirement to ensure water conservation. In a comprehensive report we explained the different greywater recycling systems available in the UK at the time, highlighting the advantages and disadvantages of each on this particular development. We calculated component and installation costs of the different systems and detailed the changes to standard waste and drainage layouts that would be required. We showed that installing 4/2.6 litre flush WCs, 8 litres/minute showers, taps with reduced flow rates at kitchen sinks and washbasins, and collecting rainwater for use in the communal garden, would be far more cost effective, carbon efficient and save more water than installing greywater recycling systems. Savings to the developers for our solution was over £1500 per flat, whilst still delivering on the planning requirement.