Profiled metal roofing tearing at fixing points
Listed under: metal, Roof, cladding, fixings and hardware, fixings, roof cladding, profiled metal
Cause
The use of rivets instead of screws does not allow thermal movement to occur
Repair
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it is important to make repairs because metal tearing or other deformation at fixing points may result in leaks through the roof
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replace rivets with roofing screws. (Nails are not recommended – they have a higher risk of coming out and a poorer seal under the head)
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where profiled metal sheet is a dark colour or a long span, allow for thermal expansion. Pre-drill 9 mm holes in the sheet roofing and install roofing screws in the hole centres with profiled EPDM sealing washers (see drawing) to allow for expansion
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screw fasteners should go through the crests (the high part of the profile) and at least 30 mm into timber purlins
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always tell someone else when you plan to work on a roof and take the appropriate safety precautions. You can find details here