Water Efficiency Calculations
We assess water consumption for new residential developments to ensure compliance with Part G of the UK Building Regulations, helping you meet sustainability goals and reduce costs.
Get a QuoteWhy Water Efficiency Calculations Matter
Water efficiency calculations estimate how much water a new development will use per person per day. They ensure compliance with Part G of the Building Regulations, help conserve resources, and reduce operational costs for occupants.
Key Factors Considered
- Flow Rates of Taps & Showers – Measures water usage from kitchen and bathroom taps.
- Toilet Flush Volume – Assesses water per flush (dual flush preferred).
- Bath & Shower Usage – Calculates typical water consumption per use.
- Dishwashers & Washing Machines – Standard consumption values if installed.
- Greywater & Rainwater Harvesting – Accounts for any water-saving technologies.
Water Efficiency Targets
Standard Requirement: ≤ 125 litres per person per day (L/p/d).
Optional Tighter Target: ≤ 110 L/p/d (some local authorities may require this).
How Calculations Are Done
Calculations follow Government-approved methodology based on installed fittings. If targets are not met, practical water-saving measures are recommended, including:
- ✅ Low-flow taps and showers
- ✅ Dual-flush toilets
- ✅ Water-efficient dishwashers/washing machines
- ✅ Greywater or rainwater harvesting systems