GRP Roof Internal Down Pipe Leaking or Condensation

[GrantMcscott]

Hi

I have a flat roof which I did myself using CureIt GRP system not finished yet as no applied the top coat.  I decided to make an internal drainage for the roof as I did not weant to put a gutter on it.

 

After it rains for a while I start to get water dripping from offset part of the down pipe but I am not sure if the roof is leaking or the pipe is sweating.

 

I did put some wool insulation in to try and keep the room air away from the pipe but it just got wet.  I do not want to spray in PU foam as incase it hides the issue of the roof leaking and the water goes else where.

 

I have been upon the roof and ran a hose and do not seem to be able to recreat the problem.

 

Any advise on what to try next?

 

Edited May 9, 2023 by GrantMcscott

[SteamyTea]

9 minutes ago, GrantMcscott said:

not finished yet as no applied the top coat

That may be your problem.

Water can easily find a path though the matrix, especially if there are some dry patches i.e. too much mat, not enough resin.

 

Sand well and get the top/flow coat on.  Then see what happens.

 

Edited May 9, 2023 by SteamyTea

[GrantMcscott]

5 minutes ago, SteamyTea said:

That may be your problem.

Water can easily find a path though the matrix, especially if there are some dry patches i.e. too much mat, not enough resin.

 

Sand well and get the top/flow coat on.  Then see what happens.

 

I was informed that the top coat was not a waterproffing coat by cureit and was worried if I put the top coat on and it was still leaking then I would not beable to fix it.   

 

The roof looks OK and enough resin and can not seem to recreat the issue with a hose unless I am not hitting the right part to make it happen.  I was going to put some more matting on in any supspect areas 

[SteamyTea]

Just now, GrantMcscott said:

The roof looks OK and enough resin and can not seem to recreat the issue with a hose unless I am not hitting the right part to make it happen.  I was going to put some more matting on in any supspect areas 

Looks a little dry in places to me.

1 minute ago, GrantMcscott said:

I was informed that the top coat was not a waterproffing coat by cureit

Really, then why do they sell it, what do they claim it is for?

 

[Conor]

Your fibreglass isn't rolled down enough into the resin and / or you've not enough on- it should look transparent, not white / milky. Put a generous topcoat on. Two layers.

Edited May 9, 2023 by Conor

[GrantMcscott]

18 minutes ago, Conor said:

Your fibreglass isn't rolled down enough into the resin and / or you've not enough on- it should look transparent, not white / milky. Put a generous topcoat on. Two layers.

What happens if that does not work what options do I have after that?

[Conor]

28 minutes ago, GrantMcscott said:

What happens if that does not work what options do I have after that?

 

I've only done the one roof so not an expert. Topcoat should do the trick, it's much more than a paint. If it doesn't, it would mean another layer of fibreglass.

[Dave Jones]

think again. 

 

get the gutter external and use edpm if you want it to last. Seen loads of horror stories with fibreglass, moves, cracks, leaks etc. None of that hassle with edpm.

 

If your making a warm room make sure you seal it from the room below to stop it sweating.

[GrantMcscott]

4 hours ago, Dave Jones said:

think again. 

 

get the gutter external and use edpm if you want it to last. Seen loads of horror stories with fibreglass, moves, cracks, leaks etc. None of that hassle with edpm.

 

If your making a warm room make sure you seal it from the room below to stop it sweating.

Going to try and find someone to put EPDM over the top as I think it needs to be all re-done and probably better to get domeone to do it

[Dave Jones]

good idea, its also a massive cold bridge running rainwater internally. its a small flat roof so less than a days work i would have thought.