I'd like to insulate my wall cavity, and there is a lot of talk about dampness problems. So I want to hear opinions, see if anyone had problems after insulating the cavity. My house is 1996 built, has solid brickwork, no cracks. I wouldn't say there is much sideway rain. Insulation to be done is polystyrene beads.
Cavity wall insulation. To do or not to do?
- Thread starter michmike
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If you read up, you're damned if you do, damned if you don't do it.
You'll either blow loads on gas for the foreseeable future... or ants may climb over the bonded polystyrene balls in your cavity and convey damp to the inner skin.
How for 1996 has it got no insulation already?
I'd risk it.
You'll either blow loads on gas for the foreseeable future... or ants may climb over the bonded polystyrene balls in your cavity and convey damp to the inner skin.
How for 1996 has it got no insulation already?
I'd risk it.
Thermal blocks, clear cavity
As for "all this talk" about dampness, it depends on who's doing the talking as to whether you should be listening. And if you do listen, what are these philosophers actually saying?
And yet poly beads have already been decided on for some reason.
And yet poly beads have already been decided on for some reason.
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Apart from having no damp, the heat loss from the house dropped dramatically after it was installed, and the rooms became more comfortable because there were not cold patches by the walls.
Bathroom became drier from lack of condensation on walls.
Bathroom became drier from lack of condensation on walls.
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I think every situation is different. When we internally insulated our 1902, I had discussions with our (old school) BC guy about interstitial condensation and also read-up as much as possible. All helped by the fact that I have a fair bit of training on condensation and humidity control from my merchant navy training (where condensation damage to cargo - before we had containers - must be avoided - it is still a problem with containers but you can't ventilate them the same as you can cargo holds). The conclusion we came to is that internal insulation would be OK because we had a well ventilated and clear cavity - lots of airbricks on external skin.
The theory being that if water gets in to the brick skins either through penetration from external or through condensation on the cooler inner skin (caused by insulation), then the well ventilated cavity would evaporate it. So far 3-4 years in I have seen nothing to contradict this - all seems good.
Cavity insulation in my house I think would be a disaster.
BTW, I am not so old that containers didn't exist when I did my training, but back in the late 70's we still had to learn stuff that hadn't really been used since the 40's and 50's....
The theory being that if water gets in to the brick skins either through penetration from external or through condensation on the cooler inner skin (caused by insulation), then the well ventilated cavity would evaporate it. So far 3-4 years in I have seen nothing to contradict this - all seems good.
Cavity insulation in my house I think would be a disaster.
BTW, I am not so old that containers didn't exist when I did my training, but back in the late 70's we still had to learn stuff that hadn't really been used since the 40's and 50's....
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If you read up, you're damned if you do, damned if you don't do it.
You'll either blow loads on gas for the foreseeable future... or ants may climb over the bonded polystyrene balls in your cavity and convey damp to the inner skin.
How for 1996 has it got no insulation already?
I'd risk it.
Yes, thermal blocks, clear cavity. If the inner thermal block skin was done properly, that is airtight, the house would be warm enough. The problem is that the builders never care and do ****ty job. When we moved in, the same winter I have found drafts almost everywhere from under the skirting board on the ground floor. It means that the cold air from the cavity gets inside the house through holes in the inner leaf, so the efficiency of thermal blocks is zero.
Mine was done with the fluffy stuff and cut the gas bill by a lot.
Never suffered any side effects.
Mind you, we ventilate our house every day, even in winter.
Our back door is usually open during the day, unless it's raining.
Never suffered any side effects.
Mind you, we ventilate our house every day, even in winter.
Our back door is usually open during the day, unless it's raining.
Well, all this talk is from the internet. These are real people, who say that they had dampness issues afterwards. But you don't know the details: maybe it was an old house with cracks in the walls, maybe they used mineral wool insulation, etc.
There are only 3 alternatives: mineral wool, poly beads, and foam. Mineral wool is a no obviously. I am hesitant between the last two.
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