Part G water calculations made simple.
Calculate your property's water consumption online and produce a professional Building Control report without the complicated spreadsheets.
Your water calculation
Your calculation in three simple steps
Answer a few straightforward questions about the property and its water fittings. We handle the calculation and report.
Tell us about the property
Choose a single dwelling or multi-plot development and enter the basic project details.
Add the water fittings
Enter the quantities, flow rates and capacities using our simple guided questions.
Get your result and report
See whether the property passes and download your professional Building Control report.
Calculate for free. Pay only for the report.
Check whether your specification passes Part G before spending anything. Purchase the professional report only when you’re ready.
Use the complete calculator and check your result without payment.
- Single and multiple dwellings
- Instant PASS or FAIL result
- Guidance for improving failed results
- No account required to start
£24 including VAT
- Professional PDF report
- Detailed calculation schedule
- Ready for Building Control submission
- Instant download after purchase
You’ll see your calculated result before being asked to purchase a report.
Everything you need to know
Straightforward answers about using the calculator and purchasing your Building Control report.
Is the water calculation genuinely free?
Yes. You can complete the calculator, see your estimated litres-per-person-per-day result and check whether the property passes without making a payment. You only pay if you choose to purchase the professional Building Control report.
What information will I need?
You’ll need basic information about the property’s toilets, wash-hand basins, kitchen and utility sinks, showers and baths. The calculator explains exactly what figures to enter at each step.
What happens if my property fails?
You can change the proposed fitting specifications and recalculate as many times as required for free. The calculator highlights the areas affecting the result and provides practical improvement suggestions.
Can I calculate multiple dwellings or plots?
Yes. You can set up multiple plots and different house types within the same development. The first report costs £20 + VAT, with each additional plot report costing £10 + VAT.
Is the report suitable for Building Control?
The report follows the Approved Document G water-efficiency calculation methodology and includes a detailed calculation schedule suitable for submission to Building Control. Final acceptance remains with the relevant Building Control body.
Do I need to create an account?
You don’t need an account to start or complete the free calculation. Account details are only required when purchasing a report, allowing you to securely access your completed reports afterwards.
Ready to check your property?
Get an instant Part G result without payment. Only purchase the Building Control report if you need it.
Start Your Free Calculation No account or payment required to start