Greywater
In some cases greywater recycling may be used as a means of reducing water consumption to achieve higher water efficiency performance levels.
Where greywater is to be used, follow these instructions to calculate the contribution from greywater (litres/person/day):
- Use the ‘Water Calculator’ to calculate the water to be recycled. Note this can only include bath, shower and wash hand basin usage. Enter this value into column (a).
- Calculate the non-potable demand for grey water of the fittings in the ‘Water Calculator’. This can include WCs and washing machines depending on the quality of the treated water.
- Calculate the percentage of used water to be recycled (greywater available divided by grey water demand) based upon manufacturer or system designer details of the system specified. Enter this percentage into column (b).
- Press ‘Calculate’ to calculate the volume of greywater used.
Notes:
Where a communal greywater system is to be provided supplying more than one home, this table can be used in the same way however the figures entered need to be apportioned down to an individual dwelling basis.