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I am currently in the process of building shed dormers on my bungalow.
I have now run into a snag and wondered if anyone can offer advice/opinons.
Its a flat roof and the drawing says "use celotex xr120 50mm cavity between joists with 1000gauge visqueen.
I did this but when the inspector came out he said there should be vents.
The drawing doesnt show nor mention any venting.
He noticed some condensation and we pulled some back down and there was damp on the underside of the deck in the void.
He checked the drawing and it says its a warm roof construction but according to the inspector the insulation goes above the deck on that type of construction.
The inspector agrees with me that the info is not clear and the drawing appears to be incorrect.
I dried some areas of the underside and fitted some of the insulation tight up against it and taped the edges.When I checked again in this cold weather there was condensation on the bare deck,I took down the bits of insulation I fitted and the roof above was dry.
Is it possible to to do this all over the roof kind of a warm roof in reverse ie working from the top deck down then cover in visqueen
http://www.rooferilkley.com/pdf/Poly_185_-_Warm_Roof_Timber_Joists.pdf
or else it will mean stripping the roof off again.
I know I wont have much of a void underneath for lights etc but Im sure I can work round that.
Ive tried to get hold of the architect and have emailed him explaining the problem but hes not getting in contact.
I have now run into a snag and wondered if anyone can offer advice/opinons.
Its a flat roof and the drawing says "use celotex xr120 50mm cavity between joists with 1000gauge visqueen.
I did this but when the inspector came out he said there should be vents.
The drawing doesnt show nor mention any venting.
He noticed some condensation and we pulled some back down and there was damp on the underside of the deck in the void.
He checked the drawing and it says its a warm roof construction but according to the inspector the insulation goes above the deck on that type of construction.
The inspector agrees with me that the info is not clear and the drawing appears to be incorrect.
I dried some areas of the underside and fitted some of the insulation tight up against it and taped the edges.When I checked again in this cold weather there was condensation on the bare deck,I took down the bits of insulation I fitted and the roof above was dry.
Is it possible to to do this all over the roof kind of a warm roof in reverse ie working from the top deck down then cover in visqueen
http://www.rooferilkley.com/pdf/Poly_185_-_Warm_Roof_Timber_Joists.pdf
or else it will mean stripping the roof off again.
I know I wont have much of a void underneath for lights etc but Im sure I can work round that.
Ive tried to get hold of the architect and have emailed him explaining the problem but hes not getting in contact.
