Part G · England · Free to use
Water efficiency calculator: 110 litres per person per day
The Appendix A calculator: litres per person per day from fittings, against the 125 or 110 l/p/d target.
Approved Document G (2015, including 2016 and 2024 amendments)
Your inputs
Results update as you type.
This calculation assumes a dwelling with both a bath and a shower. The bath-only and shower-only methods are not included.
Part G · Result
106.3 litres per person per day
Within the 110 l/p/d target with 3.7 l to spare.
Checks passed- WC (dual flush): Calculated result13.5 l
- Basin taps: Calculated result9.5 l
- Shower: Calculated result35 l
- Bath: Calculated result18.7 l
- Kitchen sink taps: Calculated result13 l
- Washing machine: Calculated result17.2 l
- Dishwasher: Calculated result4.5 l
- Sum of fittings: Calculated result111.3 l
- × 0.91 normalisation + 5 l external use: Checks passedmax 110 l/p/d106.3 l
- Fittings approach shortcut (Table 2.2): if every fitting is at or below the table value, no calculation is needed.
- Shower flow is the biggest lever: 8 to 6 l/min saves about 8 l/p/d.
Clauses this relies on
Source edition and scope
Approved Document G (2015, including 2016 and 2024 amendments).
This calculation assumes a dwelling with both a bath and a shower. The bath-only and shower-only methods are not included.
This is a preliminary check of the conditions shown. Confirm the edition, project circumstances and any additional requirements with your architect or building control.
A design aid, not legal advice. Checked against the Building Regulations 2010 for England; confirm with building control.