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Insulating behind fascia board in between joists

Discussion in 'Roofing and Guttering' started by Thepenetrator1, 30 Dec 2016.

  1. Thepenetrator1

    Thepenetrator1

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    Hi all,
    I've just done my first flat roof and I've left noggins to pick up the Fascia's where the joists run parallel to the wall. The joists overhang at the front also for the fascia. The brickwork is two course higher on the outside so I could have a smaller fascia board by the time the warm roof is finished. I have put insulation in between where the cavity should run up to the deck but should I back fill above the bricks also behind the fascia board instead of bricking in between the joists. I am a bit bothered by condensation.
    Please see photos,
    Thanks all
     

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  2. vinn

    vinn

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    Usually, you would fill the projecting joist bays with insulation.

    The flat roof framing in the photos is confusing -why have you framed like that? Do you intend to have wall plates?
    There are some other things that seem odd.
    Perhaps, you need a joiner on site to sort things out?

    Referring to your question about insulation: why not look on youtube for the steve roofer "flat roof thermal bridging" vid?
    I recommend this vid because I dont know how you intend to finish the roof.


    FWIW: rippings of 18mm or 22mm ply will act as deep fascias.
     
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  3. Thepenetrator1

    Thepenetrator1

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    Thanks vin,

    What do you mean by looks confusing?

    The outrigger joists / noggins were intended to pick up the fascia boards.

    Which part have I done wrong do you think?

    Thanks
     
  4. Thepenetrator1

    Thepenetrator1

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    Any one else out there to help?
    Thanks.

    Happy new year!
     
  5. gonch69

    gonch69

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    the only thing i will ad is you cant have your joists touching the outside (bridging the cavity)like that they will act like wicks drawing in the damp
     
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  6. Thepenetrator1

    Thepenetrator1

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    Thanks gonch.

    How would you pick up the fascia boards then from the joists then?

    I thought that's how Fascia's and soffits were fitted to joists left over hanging?
    I found these examples on the internet...
    Thanks
     

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  7. ^woody^

    ^woody^

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    Yes he can, that's a pretty standard detail.
     
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  8. ^woody^

    ^woody^

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    What you have done is standard. There are now condensation or damp issues with that.
     
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  9. Thepenetrator1

    Thepenetrator1

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    Thanks woody.

    Should I have bricked in between the outrigger joists (or whatever they're called)

    I added two course higher to the outside and notched the ends so I can have a smaller fascia.

    Thanks all, really appreciate your help as I have the rubber man coming tomorrow!
     
  10. gonch69

    gonch69

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    yes its a standard detail but touching the out side skin isnt you will draw any moisture into the timber
     
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  11. Thepenetrator1

    Thepenetrator1

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    Gonch,

    Wrap the ends in dpm?

    Cheers
     
  12. ^woody^

    ^woody^

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    Moisture from where exactly?
     
  13. ^woody^

    ^woody^

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    No, it all looks firmly constructed, and that external timber is keeping all the noggins secure and they wont be twisting.

    You've even thought about the fascia depth and will avoid those excessively deep fascias that almost all professional designers don' give a second thought about.

    Don't worry about any damp as mentioned above, the roof is covering the wall and as long as the fascia has a drip, then the top of the wall wont be getting wet.
     
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  14. chappers

    chappers

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    yep and nothing wrong with how you have notched them either, but as vinn said earlier insulate to prevent cold bridging as cold air in your roof void could cause the warm air from the building to condense as the two meet.
     
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  15. Thepenetrator1

    Thepenetrator1

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    Thanks everyone. Roof all done and covered. Filled all voids with the leftover drytherm cavity slabs.

    Thanks again.
     

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