In early 2003, we used a company to install airflex on rafters with existing insulation (glass wool) under flat concrete roof tiles of our house built in 1994. Noting recently the appearance of foam on the roof, we have just discovered the absence of counter-battens allowing the space of obligatory air circulation. Can the roofer be required to remedy this malfunction within the framework of the ten-year guarantee?
No, since the defect does not render your property "unsuitable for its purpose". You can however blame him for having posed a product having no technical advice from CSTB, according to any DTU and the effect of which may degrade your framework without, furthermore, nothing isolate.
Refer to the website under Thermal Regulation.
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