Tape beats sandbags at keeping floodwater out of homes, lab tests show
In flood tests at the University of Hull, synthetic rubber tape on the outside of a front door cut leaks by 99% and duct tape by 97-98%. Sandbags managed 70%. These were lab tests with up to 60 cm of water, and tape is no substitute for permanent flood protection or for leaving when told to.
Sandbags are the classic image of a flood. A roll of tape works far better. In tests at the University of Hull’s flood lab, sealing the gaps of a front door from the outside with synthetic rubber tape cut leaks by 99% compared with an unprotected door. Duct tape cut them by 97-98%. Sandbags managed 70%.
The tests, commissioned by Flood Re, the UK’s flood reinsurance scheme, were done in a lab with still water up to 60 centimetres deep. They protect the door, not the whole house, and they don’t replace leaving home when the authorities say so.
Six doors, up to 60 centimetres of water
Researchers at the Property Flood Resilience lab (PFRlab) tried six common door types against water up to 600 mm deep, similar to the 2007 floods in Hull, which damaged more than 8,600 homes. Aluminium tape and yellow plastic tape also beat sandbags; even the weakest tape cut leaks by 80%.
Two details made a big difference: taping the outside of the door worked much better than the inside, and an outward-opening door let in 74% less water than an inward-opening one before anything was added.
Cheaper, lighter and easier to store
“Sandbags remain a symbol of flood protection, but these tests turn that assumption on its head,” said Jonathan Kassian, Head of Flood Resilience at Flood Re. Tape is cheaper, lighter and easier to keep ready than sandbags, which rot and can become contaminated.
Temporary flood barriers gave mixed results, from full protection to complete failure, depending on how well they were fitted. “Through challenging established assumptions our research can deliver immediate benefits to householders,” said Professor Stuart McLelland, Professor of Water Science at the University of Hull.
The Environment Agency estimates that 4.6 million people in England are at risk of surface water flooding. The results will feed into Flood Performance Certificates, designed to help homeowners understand their flood risk. Where permanent protection is needed, the researchers stress, tape is not a substitute.
Photo: Don Lodge / Unsplash.
