I have a 4x8 + single garage built 10 years ago and was persuaded to the GRP route for the roofing based on a 25 year guarantee. Unfortunately, when I had a new stove burner installed last Thursday, when the installer cut a hole in the roof to fit the flue he showed me the OSB offcut which turned out to be saturated. Fortunately, the insulation blocks were preventing water ingress inside but I have no way of knowing the full extent of the leak except the underside of the adjoining garage appears to be dry whilst the whole area around the hole is kind of soft suggesting it is equally wet. The joists may be wet as well but again I don't know how badly. I have no idea where the water could have come from except maybe the lead flashing around an existing 6x2.5 ft (approx) roof light.
Naturally enough I panicked, called a roofer and he suggested replacing the whole lot with felt which carries 18 warranty. He told me GRP present no end of problems with leaks if it has not been done properly which is obviously the case here. Anyway, the quote comes to £4.800 including replacing all the OSB. It didn't strike me as horrendous although I have not signed any agreement yet. I contacted the original GRP roofer and he is coming round tomorrow to have a look . He may well try to fob me off or suggest a cheap patch up job but my instincts tell me the whole lot needs to go.
The felt roofer said the water tends to seep sideways and even though the OSB may look dry from underneath there is no way of knowing how far the water has gone above Anyway I told him I'd let him know Monday whether I wish to go ahead with him but I suspect that is what I'll do. I don't want to mess him around as hee seemed very helpful and came at a moments notice
The supplier of the GDP was Topseal and apparently, some roofers won't touch it with a barge pole whilst others think it is repairable
If I could get some kind of compensation from the GRP roofer assuming he has liability insurance that would be ideal
Anyway, I welcome whatever advice you could give me .Thanks
I just done some research and it appears there are severalon reasons why the roof leaked and all of them point to poor installation. What i have noticed particularly during the early years was loud cracking during the morning and evenings spring and autumn mainly. I put it down to teething problems but it may well have been caused by incorrect OSB being used. It should be T&G OSB to allow for expansion.
Naturally enough I panicked, called a roofer and he suggested replacing the whole lot with felt which carries 18 warranty. He told me GRP present no end of problems with leaks if it has not been done properly which is obviously the case here. Anyway, the quote comes to £4.800 including replacing all the OSB. It didn't strike me as horrendous although I have not signed any agreement yet. I contacted the original GRP roofer and he is coming round tomorrow to have a look . He may well try to fob me off or suggest a cheap patch up job but my instincts tell me the whole lot needs to go.
The felt roofer said the water tends to seep sideways and even though the OSB may look dry from underneath there is no way of knowing how far the water has gone above Anyway I told him I'd let him know Monday whether I wish to go ahead with him but I suspect that is what I'll do. I don't want to mess him around as hee seemed very helpful and came at a moments notice
The supplier of the GDP was Topseal and apparently, some roofers won't touch it with a barge pole whilst others think it is repairable
If I could get some kind of compensation from the GRP roofer assuming he has liability insurance that would be ideal
Anyway, I welcome whatever advice you could give me .Thanks
I just done some research and it appears there are severalon reasons why the roof leaked and all of them point to poor installation. What i have noticed particularly during the early years was loud cracking during the morning and evenings spring and autumn mainly. I put it down to teething problems but it may well have been caused by incorrect OSB being used. It should be T&G OSB to allow for expansion.
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