Services · Energy Design
Part G water efficiency calculations
Design-stage water calculations that satisfy Building Control and hold up on site, backed by the public health engineers who specify the fittings.
Part G of the Building Regulations covers sanitation, hot water safety and water efficiency, limiting how much wholesome water new buildings may consume. AMF MEP provides expert water efficiency calculations at design stage to demonstrate compliance, including against the tighter water targets that many planning authorities impose. By optimising water use and designing practical water conservation solutions, we help clients reduce environmental impact and operational costs across the life of the building.
A Part G calculation is only as reliable as the fittings schedule behind it, and that is where sitting inside an MEP practice matters. Our public health engineers specify the sanitaryware flow rates and appliances the calculation depends on, so the compliant design and the installed design stay aligned through construction. At Uxbridge Town Centre West the Part G water calculations sit within the complete compliance workscope we deliver alongside the full MEP design, covering 267 apartments across three blocks.
What we deliver
Discuss your project →- Part G water efficiency calculations for each dwelling type
- Fittings and flow-rate schedules aligned to the public health design
- Compliance evidence for Building Control submission
- Advice on meeting tighter planning-imposed water consumption targets
- Water conservation measures appraisal
What are Part G water efficiency calculations?
They are the design-stage calculations that demonstrate a new dwelling will not exceed the water consumption limits set by Part G of the Building Regulations. The calculation totals the consumption of every water-using fitting and appliance in the home against the applicable target, and Building Control relies on it as compliance evidence.
When should Part G calculations be carried out?
At design stage, before sanitaryware and appliances are procured. The calculation fixes the flow rates and fittings the building must be finished with, so completing it early prevents a late substitution quietly breaking compliance. We keep the calculation and the public health specification in step as the design develops.
Can you help if planning conditions demand a tighter water target than Part G?
Yes. Many local plans require new homes to meet a tighter consumption standard than the Building Regulations baseline, and we design to whichever target governs the scheme. Because we select the fittings as part of the MEP design, we can hit tighter targets through specification rather than compromise.
Need part g water efficiency calculations?
Tell us about your development and we will show you how it fits.
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