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Flat roof problems

Discussion in 'Roofing and Guttering' started by andrewlato81, 4 Feb 2015.

  1. andrewlato81

    andrewlato81

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    Hi All,
    i am having issues with flat roof . we've had 'roofers' round twice and problem still exist so im here to see what else can be done with it.
    roof is covered with metal sheet (antidrip) at angle of 3.5 deg and it seems not to drain quickly enough at the bottom. water drips into house (see pics). we had sheets lifted and it looks like water is being pushed back under sheet up to second row of battens where it stops and sips through insulation and down the walls. roof built with 225 rafters, 120mm insulation, one set of 25mm battens so plenty of air to dry bottom of sheet however it's just not happening. as per pics there are seals and drip strips at the bottom to prevent water going back. it appears problem is worse when light rain or snow melting as water not flowing fast enough???i dont know anymore. red circle indicates where problem is worst . it is happening on both bottoms(short and long run of the roof). please help....Andre
     
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  3. Alastairreid

    Alastairreid

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    Did they fit a vcl?

    Bad idea to screw through the troughs.

    The gutter looks too low as well.

    Is the insulation between the rafters?.
     
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  4. Alastairreid

    Alastairreid

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    Duplicate.
     
  5. catlad

    catlad

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    Its possible the water is coming back through capillary action, You can tap the ends of the sheets with a block of wood to create a drip edge.
     
  6. andrewlato81

    andrewlato81

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    120mm non foil kingspan between rafters(at the bottom).20mm foil faced (both side) kingspan under rafters-across rafters.then plasterboard .been told those bottom 20mm insulation should act as vcl.above insulation air gap in excess of 50mm.problem only appears during wet weather hence my theory of rain being pushed back under sheet to the 2nd row of battens. I'm thinking of lifting sheets at the bottom and sliding membrane between battens (past 2row of battens)and sheet so water drips onto it and back to the gutter?or any other ideas pls...
     
  7. andrewlato81

    andrewlato81

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    Yes was thinking even to cut half inch into valleys and bend edge down? Would this work???
     
  8. catlad

    catlad

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    You don't need to cut it you will find it will bend easily with a piece of 2x1" baton, start at about 20 degrees across the flat bit. Don't hit it to hard just keep tapping it.
     
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