To start your calculation please select which criteria from the list below you want your project to meet.
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Click on the small icons by the installation type to add data for that product to your calculation
Project Name*New buildings must have at least a toilet, washroom taps, a bath or shower, and kitchen taps.
Please select your Single flush Toilets from the drop-down lists on the left.
Once you have made your selections, click the 'Add to calculation' button to add the data into the main calculation table.
Please select your Dual flush toilets from the drop-down lists on the left.
Once you have made your selections, click the 'Add to calculation' button to add the data into the main calculation table.
Please select your Taps (excluding kitchen/utility room taps, bath/shower taps, and external taps) from the drop-down lists on the left.
Once you have made your selections, click the 'Add to calculation' button to add the data into the main calculation table.
Please select your Bath from the drop-down lists on the left.
Once you have made your selections, click the 'Add to calculation' button to add the data into the main calculation table.
Please select your Shower from the drop-down lists on the left.
Once you have made your selections, click the 'Add to calculation' button to add the data into the main calculation table.
Please select your Kitchen taps from the drop-down lists on the left.
Once you have made your selections, click the 'Add to calculation' button to add the data into the main calculation table.
* BS 8515 intermediate approach.
Your target maximum consumption of potable water is 110 litres per person per day.