GRP flat roofing

[DAVID barnish]

I have just had a new small extension built with a GRP flat roof. The day after completion it rained and there was a lot of ponding. I asked the builder why it wasn't falling to the gutters and his response was that it is a GRP flat roof so there are no falls. Is this correct, what is the point of having guttering if it doesn't run into it, I appreciate it should be watertight but is he right, and could it be remedied or indeed does it need to be remedied

 

[bobasd]

all flat roofs need to fall so that they can discharge ther water. so all flat roofs are built with a slope to the gutters.ponding is always bad news esp on a new roof. not that its immediately goin to leak but it shouldnt be ther.

some roofs with ponding can last while others will develop a weak spot and eventuly begin to leak.

unless you are goin to rebuild the roof then thers not much you can do about it.

 

[DAVID barnish]

Yes I think his main point was that as it was a GRP roof so there is no need for it to fall, as you say doubt anything can be done

 

[bobasd]

grp nothin, it should be built with falls.

 

[Buck_68]

It should fall and the sides should have raised edges to prevent the rain water spilling over the sides.

Ours falls to the front edge (i think it is about a 5 degree slope to accommodate the velux flat roof lights) into the guttering and each side is raised as above. No pooling of water.