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Effective flood testing for locating roof leaks

Updated: Mar 21

Flood testing is a widely recognised and effective method for roof leak detection and offers a comprehensive and efficient solution for identifying leaks in flat roofs.

This technique involves temporarily creating an artificial ponding of water on the roof surface to simulate heavy rainfall conditions.

By observing the behaviour of the water and identifying any signs of internal leakage, professional testers can establish the integrity of the waterproofing membrane. Thornton Consulting has a team of highly professional Consultants and Field Testers who with skill and expertise, will always ensure the right testing procedure is carried out to locate any breaches in the roof waterproofing membrane.

The process of flood testing begins with an assessment and moisture profile of internal surfaces to determine any existing areas of damp. Externally, rainwater outlets are bunged and areas bunded if necessary to form a boundary for the test. Then, a controlled amount of water is distributed evenly across the roof surface, gradually increasing the water level to simulate a significant rainfall event. During the testing, the roof will be closely monitored and the internal and external areas examined for signs of leakage or an increase in moisture.

This flood testing method has several advantages over alternative leak detection methods. It provides a comprehensive evaluation of the entire roof surface, including laps, penetrations, and other vulnerable areas.

The test can be carried out to buried membranes, beneath paving or green roofs for example, which can prove problematic for electronic leak detection test methods and can eliminate the need to remove finishes to expose the waterproofing if it proves to be watertight.

Flood testing can be conducted on both new and existing roofs, making it suitable for construction projects as well as routine maintenance inspections and leak investigations and trace dyes can be incorporated into the test water to positively establish the source of a leak where necessary.

It is important to note that flood testing should only be performed by experienced professionals to ensure accurate results and minimise any potential risks, as there are some situations where the test is not appropriate. Thornton Consulting are always happy to offer advise to ensure we provide the most appropriate test for each situation.

By employing this method, Building Owners, Facility Managers and Main Contractors can identify and address leaks in a timely manner, ultimately protecting their assets and extending the lifespan of their roofs. Thornton Consulting offers a comprehensive and cost-effective property leak detection and analysis for clients throughout the UK and the Republic of Ireland, with all work carried out under the company’s core values. Call us today on 01342 410508 or use the Contact Form to get in touch


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