I don't get the logic of warm roofs. Is it just to convince people to completely change their roof design and make a lot of money ?!! (that's a joke okay)
If you put a vapour barrier down above the ceiling ... okay where is the vapour in the dwelling gonna go? Anybody think about this? It's a roof project but now you made it a problem for the dwelling itself. People breathe, shower, cook ... every day, more vapour ... where does it go? Are you going to drill holes in the wall?
Especially with the vinyl paint etc... I would say a roof that vents even more vapour than normal is what you want these days. Sealing yourself in with plastic is insanity. What will you do install extractors in every bedroom? Okay I have no idea if this is actually a problem in real life.
Is fresh air bad for your cholesterol these days?
Warm roofs with all their layers of insulation do have small air spaces between layers, just under the deck ... is the deck not going to be cold? Of course it is. So a warm roof isn't actually a warm roof, it is mostly warm apart from at the edges were its cold and you'll get condensation. Seems like an impossible dream. Maybe one of Greta's dreams? Another EU regulation?
Anyway, seems to me that accepting that people breathe and cook and letting the roof breathe is fault tolerant and superior, and not full of strange ideology, of course as long as you vent it properly.
Or is the whole point of warm roofs to remove the need for ugly vents? You could do a trench vent against the wall like Steve Roofer does on youtube, or sofits, if mushrooms too ugly.
Underside of plywood can be waterproofed for longevity, and as regards cold bridging glueing sheet rubber on the top of the joist before ply is screwed through will prevent most of it I imagine.
Then you can vapour all your like in a cold roof and you don't have unrealistic expectations of having no vapour. Nor do you try to change the fundamentals of vapour flow that the dwelling has always been designed for. Nor do you require venting changes in the dwelling itself. Nor do you have kingspan underneath the roof covering which doesn't take ladders well.
- Ah mate it's Friday, I can't be bothered to do this roof. Let's just stick the insulation on top and cover it.
- Are you crazy, that'll never work, what about condensation.
- er ... there ... won't be any because ... hmm ... it's a warm roof, very special and high tech.
- High tech eh, well alright but how will we do the venting.
- What time is ? er ... no vents. We don't need them. It's high tech I told you. From the future.
- Oh yeah ....
- But, let's take the plasterboards off downstairs and stick a bit of plastic up there ... just in case, nudge nudge wink wink, to prevent the moisture going up.
- Moisture going up, or moisture going down?
- ... look it's 1:30, we haven't time for questions, just get the roller out.
- er Hello Sir, we gonna do a special roof for you, brand new, Warm Roof, just like on the Internal Space Station, no moisture at all not like the old days, the science has changed ... makes your roof look very proud, a bit taller and ... only costs 20% extra. Be ready by 5pm.
If you put a vapour barrier down above the ceiling ... okay where is the vapour in the dwelling gonna go? Anybody think about this? It's a roof project but now you made it a problem for the dwelling itself. People breathe, shower, cook ... every day, more vapour ... where does it go? Are you going to drill holes in the wall?
Especially with the vinyl paint etc... I would say a roof that vents even more vapour than normal is what you want these days. Sealing yourself in with plastic is insanity. What will you do install extractors in every bedroom? Okay I have no idea if this is actually a problem in real life.
Is fresh air bad for your cholesterol these days?
Warm roofs with all their layers of insulation do have small air spaces between layers, just under the deck ... is the deck not going to be cold? Of course it is. So a warm roof isn't actually a warm roof, it is mostly warm apart from at the edges were its cold and you'll get condensation. Seems like an impossible dream. Maybe one of Greta's dreams? Another EU regulation?
Anyway, seems to me that accepting that people breathe and cook and letting the roof breathe is fault tolerant and superior, and not full of strange ideology, of course as long as you vent it properly.
Or is the whole point of warm roofs to remove the need for ugly vents? You could do a trench vent against the wall like Steve Roofer does on youtube, or sofits, if mushrooms too ugly.
Underside of plywood can be waterproofed for longevity, and as regards cold bridging glueing sheet rubber on the top of the joist before ply is screwed through will prevent most of it I imagine.
Then you can vapour all your like in a cold roof and you don't have unrealistic expectations of having no vapour. Nor do you try to change the fundamentals of vapour flow that the dwelling has always been designed for. Nor do you require venting changes in the dwelling itself. Nor do you have kingspan underneath the roof covering which doesn't take ladders well.
- Ah mate it's Friday, I can't be bothered to do this roof. Let's just stick the insulation on top and cover it.
- Are you crazy, that'll never work, what about condensation.
- er ... there ... won't be any because ... hmm ... it's a warm roof, very special and high tech.
- High tech eh, well alright but how will we do the venting.
- What time is ? er ... no vents. We don't need them. It's high tech I told you. From the future.
- Oh yeah ....
- But, let's take the plasterboards off downstairs and stick a bit of plastic up there ... just in case, nudge nudge wink wink, to prevent the moisture going up.
- Moisture going up, or moisture going down?
- ... look it's 1:30, we haven't time for questions, just get the roller out.
- er Hello Sir, we gonna do a special roof for you, brand new, Warm Roof, just like on the Internal Space Station, no moisture at all not like the old days, the science has changed ... makes your roof look very proud, a bit taller and ... only costs 20% extra. Be ready by 5pm.
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