Finding insulation advice
Discussion
As the cold days draw in we’re discovering that our newly bought 80s house needs to have its insulation sorted.
We have a quite specific issue however where one of the upstairs rooms sits above the roofline, so the floor is in line with the eaves. We had the floorboards up recently for some plumbing work and you could feel cold gushing in from the eve. If you walk in the room despite new carpet/underlay, the floor is freezing and the room is very cold. There is some floor insulation (the stuff that comes in what looks like red bags), but is not packed in I assume to allow for ventilation.
We need advice on how to sort this issue as well as renew the insulation in the rest of the house. There are plenty of companies out there but we obviously want someone reputable who can offer the best advice and not charge us for stuff we don’t need, installs something that will causes damp etc. And unfortunately we’ve missed the boat on any government grants.
So, with all that, any company recommendations and/or advice much appreciated.
We have a quite specific issue however where one of the upstairs rooms sits above the roofline, so the floor is in line with the eaves. We had the floorboards up recently for some plumbing work and you could feel cold gushing in from the eve. If you walk in the room despite new carpet/underlay, the floor is freezing and the room is very cold. There is some floor insulation (the stuff that comes in what looks like red bags), but is not packed in I assume to allow for ventilation.
We need advice on how to sort this issue as well as renew the insulation in the rest of the house. There are plenty of companies out there but we obviously want someone reputable who can offer the best advice and not charge us for stuff we don’t need, installs something that will causes damp etc. And unfortunately we’ve missed the boat on any government grants.
So, with all that, any company recommendations and/or advice much appreciated.
Sounds like a pretty standard room-in-roof scenario.
Any competent Architect or Architectural Technologist will be able to advise.
There shouldn't be any insulation under the floor usable part of the floor: the room itself should lie within the insulated envelope of the building.
Are there any knee walls? If there are, then the bottom of the following images would be the normal way to do it (ie. you insulate only the part of the floor that lies beyond the knee wall).
If there are no knee walls, then there should be no insulation in the floor (or at least only around the very perimeter, if necessary) and the insulation at roof rafter level should link to that in the main external walls; but you do need to design this bit right to prevent interstitial condensation: you need either a 50mm. air gap over the rafter level insulation, or a breathable roofing membrane. In both cases, you'll probably want both insualtion between the rafters and a layer of insulated plasterboard beneath them, to give sufficient total insulation and to minimise thermal bridging caused by the rafters themselves.
Any competent Architect or Architectural Technologist will be able to advise.
There shouldn't be any insulation under the floor usable part of the floor: the room itself should lie within the insulated envelope of the building.
Are there any knee walls? If there are, then the bottom of the following images would be the normal way to do it (ie. you insulate only the part of the floor that lies beyond the knee wall).
If there are no knee walls, then there should be no insulation in the floor (or at least only around the very perimeter, if necessary) and the insulation at roof rafter level should link to that in the main external walls; but you do need to design this bit right to prevent interstitial condensation: you need either a 50mm. air gap over the rafter level insulation, or a breathable roofing membrane. In both cases, you'll probably want both insualtion between the rafters and a layer of insulated plasterboard beneath them, to give sufficient total insulation and to minimise thermal bridging caused by the rafters themselves.
Equus said:
Sounds like a pretty standard room-in-roof scenario.
Thanks Equus, that diagram describes what’s going on perfectly. I have no idea what’s in the wall at the moment, but underneath it’s just a void between the eaves and the room, hence the problem. I guess the question to your point is finding someone who knows what they’re doing to retrofit the best solution. It will probably need investigation to ensure adequate air flow etc. do you have any advice how I go about finding someone? I really want to go on recommendation, but the local groups haven’t turned up anything, and it’s impossible to tell if anyone is going to do a proper job through googling etc.
juggsy said:
Thanks Equus, that diagram describes what’s going on perfectly. I have no idea what’s in the wall at the moment, but underneath it’s just a void between the eaves and the room, hence the problem.
I guess the question to your point is finding someone who knows what they’re doing to retrofit the best solution. It will probably need investigation to ensure adequate air flow etc. do you have any advice how I go about finding someone? I really want to go on recommendation, but the local groups haven’t turned up anything, and it’s impossible to tell if anyone is going to do a proper job through googling etc.
Interested in this too as I think I may have to go down the route of getting a professional in rather than trying to DIY, mainly because I can't actually bring myself to go into the loft as I'm terrified of the spiders. Pathetic I know, but I just can't do it! I guess the question to your point is finding someone who knows what they’re doing to retrofit the best solution. It will probably need investigation to ensure adequate air flow etc. do you have any advice how I go about finding someone? I really want to go on recommendation, but the local groups haven’t turned up anything, and it’s impossible to tell if anyone is going to do a proper job through googling etc.
I'm also looking at this, as some of this house is uninsulated (above my bedroom, annoyingly) and some of it has old, thin insulation. The knee walls aren't insulated at all, and when the upstairs toilet was installed, the installers didn't feel the need to seal around the hole in the back wall that the pipe goes through.
Trouble is, the crawl spaces are also used for storage, so I'm trying to balance out insulation with still being able to use the space. I'd planned to board over some of the top space above the rooms in the roof, but where there is insulation, there isn't a 50mm gap to the top of the joists. If I use spacers, there will be a much smaller space above them. And I can't do that in the centre, because the water tanks are there. I may well just up with making it "better" rather than "best", though it may be difficult to find the thin insulation material.
Trouble is, the crawl spaces are also used for storage, so I'm trying to balance out insulation with still being able to use the space. I'd planned to board over some of the top space above the rooms in the roof, but where there is insulation, there isn't a 50mm gap to the top of the joists. If I use spacers, there will be a much smaller space above them. And I can't do that in the centre, because the water tanks are there. I may well just up with making it "better" rather than "best", though it may be difficult to find the thin insulation material.
We definitely want a professional in as not only do we not want to deal with all the horrible old insulation in the loft, the main issue is getting the cavity walls sorted as well as the knee wall as mentioned above. Still struggling to find someone suitable on recommendation though, and I fear finding any old person may bring the snake oil salespeople...
If it's someone to actually install it you're after, then it would be nice to think that anyone who specialises in loft conversions would understand the principles involved.
Sadly, I'm not sure that this is the case... but unfortunately you're just going to have to take your chances, as employing a separate professional (Architect, Chartered Architectural Technologist or Chartered Building Surveyor) just to specify and supervise someone else to do the work is likely to be prohibitively expensive.
Your best bet might be to try to gain an understanding of the issues yourself, so that you can have an informed conversation with whoever you ask to quote for the work, in order to judge their competence directly.
Sadly, I'm not sure that this is the case... but unfortunately you're just going to have to take your chances, as employing a separate professional (Architect, Chartered Architectural Technologist or Chartered Building Surveyor) just to specify and supervise someone else to do the work is likely to be prohibitively expensive.
Your best bet might be to try to gain an understanding of the issues yourself, so that you can have an informed conversation with whoever you ask to quote for the work, in order to judge their competence directly.
Equus said:
If it's someone to actually install it you're after, then it would be nice to think that anyone who specialises in loft conversions would understand the principles involved.
Sadly, I'm not sure that this is the case... but unfortunately you're just going to have to take your chances, as employing a separate professional (Architect, Chartered Architectural Technologist or Chartered Building Surveyor) just to specify and supervise someone else to do the work is likely to be prohibitively expensive.
Your best bet might be to try to gain an understanding of the issues yourself, so that you can have an informed conversation with whoever you ask to quote for the work, in order to judge their competence directly.
Agreed, we definitely don't want to go down the route of a surveyor (already bad experience with one on another matter), so will have to get a few people in for some quotes I think. Thanks!Sadly, I'm not sure that this is the case... but unfortunately you're just going to have to take your chances, as employing a separate professional (Architect, Chartered Architectural Technologist or Chartered Building Surveyor) just to specify and supervise someone else to do the work is likely to be prohibitively expensive.
Your best bet might be to try to gain an understanding of the issues yourself, so that you can have an informed conversation with whoever you ask to quote for the work, in order to judge their competence directly.
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