How do I plasterboard and insulate my conservatory roof..?
Discussion
Hi, many thanks to the previous posters and apologies if I have missed something already answered, but here goes....
I have a timber frame lean-to style conservatory with polycarb roof and have been looking at ways to make it more habitable. Given the size and spacing of the beams, it feels like this is a simple enough project, however famous last words and all that. My biggest concern is opening a can of worms with Building Control as I'm not sure the existing structure built by the previous owners is compliant. I thought there was something about needing a segregation from the house by a door and requiring a separate heating system? Neither of which this has.
I want to basically insulate between the beams and then plaster the underside. Intention is for rooflights (non opening) at 3No. of the 5No. spacings where the beams are straight/parallel. Apart from these rooflights I planned to leave the remaining polycarb as is. I'm presuming the rooflight frames would need to be sat on builders kerbs built on top of the beams. But then I'm a little confused what I'd need to do with the kerb trims? Glue these over the adjacent polycarb panels? The existing poly roof is water tight, but I was also thinking maybe a generous application of mastic underside of the existing panels?!
My initial thoughts for the insulation was just to use foil backed insulation, cut to fill the gap between each beam, wedged straight up against the polycarb underside, with the insulation the depth of the beam. Then just plasterboard fixed to the beam undersides.
I'm a little unsure of the science around the ventilation requirements to prevent condensation sorry....does there need to be no air gap on the underside of the polycab? In which case wedging up the insulation to fill the entire void under the plastic sheet and between the beams would work? Or does the foil vapour barrier need to be a continuous piece? In which case my proposal wouldn't work due to only having foil between the beams?
Apologies for the information overload and for too many questions! Any and all suggestions of what to do with the space are welcome. Thanks in advance.
I have a timber frame lean-to style conservatory with polycarb roof and have been looking at ways to make it more habitable. Given the size and spacing of the beams, it feels like this is a simple enough project, however famous last words and all that. My biggest concern is opening a can of worms with Building Control as I'm not sure the existing structure built by the previous owners is compliant. I thought there was something about needing a segregation from the house by a door and requiring a separate heating system? Neither of which this has.
I want to basically insulate between the beams and then plaster the underside. Intention is for rooflights (non opening) at 3No. of the 5No. spacings where the beams are straight/parallel. Apart from these rooflights I planned to leave the remaining polycarb as is. I'm presuming the rooflight frames would need to be sat on builders kerbs built on top of the beams. But then I'm a little confused what I'd need to do with the kerb trims? Glue these over the adjacent polycarb panels? The existing poly roof is water tight, but I was also thinking maybe a generous application of mastic underside of the existing panels?!
My initial thoughts for the insulation was just to use foil backed insulation, cut to fill the gap between each beam, wedged straight up against the polycarb underside, with the insulation the depth of the beam. Then just plasterboard fixed to the beam undersides.
I'm a little unsure of the science around the ventilation requirements to prevent condensation sorry....does there need to be no air gap on the underside of the polycab? In which case wedging up the insulation to fill the entire void under the plastic sheet and between the beams would work? Or does the foil vapour barrier need to be a continuous piece? In which case my proposal wouldn't work due to only having foil between the beams?
Apologies for the information overload and for too many questions! Any and all suggestions of what to do with the space are welcome. Thanks in advance.
Edited by marshac on Friday 1st October 20:33
There is no proper way to add any roof lights to that. Anything is going to be a total bodge and probably leak. If you frame up under the rafters and insulate properly before you plasterboard then you should get a lot warmer room for not a huge amount of money. Don’t mention anything to building control since as you all ready know your conservatory is not up current regs.
Edited by J6542 on Friday 1st October 21:17
Eye, thought as much cheers. Other option if we really wanted rooflights was to rip the whole polycarb off, membrane, batten, and superlight tiles or similar... I could then frame-out properly for the rooflights.
When you say 'insulate properly'...I’ve never done it pal sorry...is foil backed insulation hard-up against the underside of the polycarb correct?
Cheers
When you say 'insulate properly'...I’ve never done it pal sorry...is foil backed insulation hard-up against the underside of the polycarb correct?
Cheers
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