Had a GRP garage roof job done, pooling. Is this normal?

[billyboy1234]

Had a roof replaced on our garages, and to be fair to the fitter, there was never really a sufficient run on the original roof. He had increased the run when he did the work. However last night we had our first substantial rainfall, and whilst everything is dry inside (which is a vast improvement on before), there is some pooling on the roof.

He did say this is to be expected on a roof of this size, is he correct? Should we be concerned?

Thanks.

Pic

 

[honda]

Were the boards done at the same time as the old ones can sag hence the pooling. Had my garage done 14 years and rain pools just in one corner but with no problems. The house across the road has pooling like yours every time it rains with no problems or leaks so if it was me I wouldn't be concerned.

 

[billyboy1234]

The boards and most of the joists were replaced too. He used 18mm OSB board and did 3 layers of GRP.

 

[freddiemercurystwin]

Pooling is caused because of lack of fall, even if the joists are sagging a bit the fall should be enough to cope with that issue. Your roofer simple did not add enough fall, this could have been done with firings on top of the existing joists. The size of the roof is irrelevant. Anyway, provided the GRP has been installed correctly it won't be a problem, apart from aesthetic and winding you up every time you see it pooling for ever more!

 

[honda]

Just to add to Freddy's post what does wind me up (only a little) is the fact that when the pool eventually evaporates it leaves over time a sediment of dirt etc which I scrub off once a yearish for the sake of appearances.