Water Calculations
Water calculations are crucial for determining a building’s water usage and demand. Furthermore, they help design efficient systems that comply with Part G of the Building Regulations, aiming to reduce consumption and promote sustainability. In addition, these calculations are especially important for new residential buildings to minimize environmental impact and meet water efficiency standards.
What are Water Efficiency Calculations?
A water efficiency calculation is required under Part G of the Building Regulations for all new builds and conversions. Part G mandates that a dwelling must not exceed 125 liters of water use per person per day. Stricter targets, like 110 liters per person per day, may apply in some areas, particularly those following the London Plan.
Water calculations consider the efficiency of various fixtures and systems, including toilets, baths, showers, taps, dishwashers, and washing machines, along with flow rates, fixture capacity, and water-saving technologies.
What Impacts Water Calculations?
Several factors affect a water calculation, such as the flow rates of taps and showers, bath capacity, and toilet flush volumes. The presence of systems like rainwater harvesting or water softeners also influences the result. Each factor contributes to the total water usage, helping ensure the building meets efficiency standards
When Should I Get a Water Calculation?
The best time to conduct a water calculation is during the design stage. This allows time to choose compliant fixtures and fittings, and gives us the opportunity to guide you in meeting your water efficiency target. Completing the calculation early also helps speed up the building control approval process, reducing delays and keeping the project on schedule.
What Information is Needed?
In order to conduct a water calculation, we require detailed information on the following:
- A list of all water-using fixtures and appliances, such as showers, baths, sinks, toilets, dishwashers, and washing machines.
- Specifications for any products you plan to install, including flow rates and capacities, to ensure they meet efficiency goals.
- Information on flow rate and water pressure within the system, as these factors impact overall efficiency.
With this information, we can accurately calculate your expected water consumption and provide recommendations to meet efficiency targets.
Summary
Water calculations are key to designing efficient and sustainable water systems in new buildings. By assessing water demand, optimizing usage, and meeting regulatory requirements, builders can reduce waste and support responsible water management.
Conducting water calculations early allows UK builders and developers to lower costs, reduce environmental impact, and promote sustainability. Contact us today our team is here to help ensure your project meets all water efficiency standards for a more sustainable future.
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