In England, we put the vapour control layer the warm side of the roof we also don’t vent our warm roofs.
I have watched a few of your videos in regards to flat ‘warm roofs’ on YouTube and have found them to be of great guidance with my current new build extension. Accordingly, I would be most grateful if you would answer a couple of questions that I have regarding your video posted on YouTube entitled ‘Thermal Bridging of a insulated flat roof through the front fascia’.
I want to put a second layer of ply sheet on top of the insulation board, I can screw that down around the edges, but want to put a line of fixings down the middle, but this would mean going through the board until I get to the ply underneath.
I currently have a flat roof extension for my bathroom and kitchen, this is how I bought the house, but it has no insulation and it leaks also. My walls are cavity on the extension but they are not insulated, my question is, would I be better fixing the roof with a warm roof or filling the walls with insulation?
In this video I explain problems with insulating a roof using the warm and cold roof construction methods. Whatever new flat roof covering you choose, e.g. EPDM rubber, Kemper, Liquid Rubber Triflex, if the specification of the insulation is not correct you could have problems which could include rotting joists.
New flat roofs using the warm and cold flat roof methods. New flat roofs in London and the UK need to come up to the new building regulations. In this video I try to explain the difference between the two methods of construction for a new warm flat roof and a new cold flat roof.
Hopefully this video will help explain the difference between cold flat roof construction and warm flat roof construction, this video shows detailed drawings on how a cold flat roof is constructed. I link to two other videos, one on warm flat roof construction and one that’s an in depth comparison between cold and warm flat roofs also showing thermal imaging of poorly performing, insulated flat roofs. The animation program used was Sketch Up with lots of section cuts.