DIY Doctor UK DIY Forums

I had an extension built 2 years ago and opted for fibre glass instead of felt roofing because it has a longer life span.Trouble is i am getting the most unbelievably loud banging noises coming from it.The manufacturers ,Topseal, have been of little help and I cant find much on the net.
Apparently its to do with different expansion and contraction between the wooden structure and the fibre glass as it heats and cools down.Now i dont know whether my roof is at risk but what i do know is that if i ever choose to sell this house i may have problem doing so because of the noise.I just wonder if anyone has any experience of this kind of roofing and any suggestions?

I'm afraid what your experiencing is totally normal for GRP / Fibreglass roofs, and it's why they crack so often.

The reasons given are correct. The contractor should have put suitable expansion joints in to prevent this, but 99.99999% of fibreglass roofers don't bother because it's more hassle and more work, and more cost.

You need to inspect this roof regularly, because if you're getting the loud cracking noises, the fibreglass will delaminate away from the substrate and then actual cracks won't be more than a year or two away.

When it finally goes, if you can't get it sorted under the "guarantee" I would not recommend you replace with fibreglass.

We fit a fibre reinforced EPDM rubber roof - and in 52 years and over 1 billion square meters laid worldwide they have not had a product failure - no fibreglass roof system I know can claim that.....

About 1/3rd of our works per year is replacing failed GRP roofs - most of which are about 2-5 years old.

Where are you based - I am sure someone local could come and have a look....