PPS 15 Planning and Flood Risk (Revised)·Page 77·E6
Tanking of internal floors and basement walls
Waterproof membranes and sheets seal solid concrete walls and floors to prevent flood water or high groundwater from entering. Solid floors provide added weight to resist uplift pressures from flood water.
This measure may be used to prevent flood water or high groundwater entering the building. It involves the use of solid concrete walls and floors, which are then sealed with waterproof membranes / sheets. Solid floors have the added advantage that with their extra weight they are able to cope better with the uplift pressures from the flood water.
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