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GRP roof leaking and holds water

Discussion in 'Roofing and Guttering' started by paulc8888, 7 Jul 2019.

  1. paulc8888

    paulc8888

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    Hi all

    I have recently had a new GRP roof installed. New joists were installed to provide a fall for rainwater. The roof seems to retain water due to the roof rising just before the guttering. Is this correct? Also, should the skylight have some kind of flashing rather than the silicone pictured? We have also had two leaks. The first one the roofer accepted responsibilty, a hairline crack in the fibreglass, the second he is less accepting.

    Any advice would be most welcome.

    Regards, Paul
     

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  2. foxhole

    foxhole

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    Can’t see much but should not be able to see any bare timber on a roof .
     
  3. Rufus Raintight

    Rufus Raintight

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    Can you share some more photos of the roof?
     
  4. paulc8888

    paulc8888

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  5. paulc8888

    paulc8888

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  6. paulc8888

    paulc8888

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    Sorry, not the greatest pictures
     
  7. ajstoneservices

    ajstoneservices

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    That is a pi55 poor job.
     
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  8. paulc8888

    paulc8888

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    Yes, I'm not a roofer, but that sums up my thoughts. Standard throughout is low. Is there anything in particular that catches your eye?
     
  9. Mw Roofline

    Mw Roofline

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    A little pooling is acceptable on a grp roof but they need to come back and finish the job around the skylight.
     
  10. paulc8888

    paulc8888

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    OK, thanks for your advice
     
  11. Notch7

    Notch7

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    I find the mesh tends to get doubled up near the edge which creates a bit of a ridge.

    Ponding should be more than 2 or 3mm deep though and should only be localised.

    When falls are as shallow as 1 in 60 it only takes a bent joist or a bit of uneven grp to create some ponding.

    Shallow ponding doesnt cause a problem, its just not ideal.
     
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  12. Leofric

    Leofric

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    I think it warrants a WTF for most of what is going on there .
     
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  13. bobasd

    bobasd

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    as most have said above, there's a number of things just plain wrong or that could have been done much better.




    its irrelevant who did your roof - the thing is it should all come off and be re-done by a Roofer.
    not least there doesn't seem to be any fall to the rafters resulting in the the ponding not even reaching the drip edge (is there a drip edge?).
    i'd go for a fall of about 1:48.
    how does water discharge from the skylight glass - or does it just build-up and spill over?
     
  14. noseall

    noseall

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    The pictures are rubbish, although it looks like the detailing under the roof tiles looks poor, even from what I can see.
     
  15. oldbutnotdead

    oldbutnotdead

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    If the resin has cracked it indicates that your 'roofer' hasn't created a solid deck. GRP is strong but brittle- if the deck sheets are floating about then you'll get more cracks. What did he use for the deck?- 18mm t & g OSB is favourite.
    The ponding is a combination of lack of fall and raised edge trims- no good to you now but you do get a neater job if you rout the trims into the deck.
     
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