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Vapour Control - Flat roof

  • 29-10-2012 09:01PM
    #1
    jimmytom
    Registered Users, Registered Users 2 Posts: 31 ✭


    Hi All,

    I have recently a flat roof constructed as part of new build, however i am not sure as to whether a vapour control layer has been installed under the insulation, most likely not. Can i do anything to ensure there is no future problems with condensation etc. I have yet to slab under the roof joists. Also would the introduction of insulation between the roof joists as well as the insulation which has already been installed above the roof deck cause any issue?

    Any info much appreciated.

    Regards

    Jimmytom


Comments

  • #2
    bdoo
    Closed Accounts Posts: 574 ✭✭✭bdoo


    jimmytom wrote: »
    Hi All,

    I have recently a flat roof constructed as part of new build, however i am not sure as to whether a vapour control layer has been installed under the insulation, most likely not. Can i do anything to ensure there is no future problems with condensation etc. I have yet to slab under the roof joists. Also would the introduction of insulation between the roof joists as well as the insulation which has already been installed above the roof deck cause any issue?

    Any info much appreciated.

    Regards

    Jimmytom

    If the insulation is above the deck there should be little fear of condensation as there won't be a cold surface where moisture can condense. Foil backed plasterboard could be used as a vapour barrier.

    What kind of a room is the roof over? Will there be much moisture produced in it.


  • #3
    jimmytom
    Registered Users, Registered Users 2 Posts: 31 ✭jimmytom


    bdoo wrote: »
    If the insulation is above the deck there should be little fear of condensation as there won't be a cold surface where moisture can condense. Foil backed plasterboard could be used as a vapour barrier.

    What kind of a room is the roof over? Will there be much moisture produced in it.

    Thanks for the speedy reply - the roof will be over a hallway porch and utility. I'll use foil backed plasterboard. from my research a vapour control layer is noticed as a must under the insulation above the roof deck. i suppose my fear would be that the roof deck becoming damaged due to condensation. would the introduction of insulation in between the joists of the roof deck cause issues?

    many thanks for your help to date


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