Are you building, extending, or converting a property in Luton? UK law has required a Part G water efficiency calculation since 2010. It applies to new dwellings, most conversions, and some extensions.
Part G limits how much drinking-quality water, known as potable water, a home can use. The standard mandatory limit is 125 litres per person per day. Some local planning authorities set a stricter optional target of 110 litres per person per day. We’ll confirm which target applies to your Luton project before you start.
Part G of the Building Regulations covers sanitation, hot water safety, and water efficiency in buildings. The water efficiency element sets a maximum daily water use per person, measured using an approved calculation method.
Water outflow is one of the main factors behind unnecessary energy use in a home. A Part G water calculation makes sure a new build in Luton wastes as little water, and the energy needed to heat it, as possible.
Get a water efficiency calculation done before construction starts. This lets you find out whether your plans comply before you spend money on fixtures and appliances. If your design falls short of the target, you can adjust the plans rather than the finished structure. Sorting this at the design stage, not after building work, saves both time and cost.
The standard method is the Water Efficiency Calculator for New Dwellings. It takes flow rates and volumes for every water-using fitting in the property, including toilets, taps, showers, and appliances. Occupancy levels, the number and type of fittings, and how often they’re used all feed into the result.
We take the flow-rate and consumption data straight from manufacturer specifications when we run the calculation for you. You’ll need to submit the finished calculation as part of the building control process, to demonstrate compliance with Part G.
The government has consulted on tightening the Part G limits further, to 105 litres per person per day mandatory and 100 litres per person per day optional, with implementation targeted for 2026. If this affects your build timeline, ask us for the latest position when you book — we’ll confirm the current requirement before your calculation goes ahead.
You need this calculation for all new build dwellings and for many conversions in Luton. Some extensions need one too, depending on the scope of work. If you’re unsure whether your project qualifies, get in touch and we’ll check for you.
Contact us on 07500300909 or info@theepccertificatelondon.co.uk to book your Part G water calculation, or to check whether your Luton project needs one.
Call us on 07500300909 to see how we can help with your Part G water calculation in Luton.
We also offer a range of other expert services, including SAP EPC, EPC Certificate, Property Photography, Floor Plans, Fire Risk Assessment, Asbestos Survey, and Legionella Risk Assessment.