Cavity Wall Insulation

Fisherman

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1980s Bungalow, Block Cavity Wall construction, cavity fitted with the old 2" white aeroboard, as used back then. Can additional cavity-fill be pumped in against the aeroboard?
 
I have a 2000s house with cavity wall construction, 50mm polystyrene and 50mm gap in the cavity. I intend to get it pumped later this year, lots of companies doing it and there’s a grant for it. Curious if others will chip in with caveats etc.
 
All bonded bead used in cavity wall insulation should be certified. The certificates are readily available to inspect online. Here is an example of one. The home owner should ask the installer for a copy of the certificate for the product being proposed. Before agreeing to proceed, these should be read and understood by the home owner to understand if the house is suitable or not. Just because there's a grant and your house qualifies doesn't mean it is a good idea!
 
Good!.... From what I can see around the meter box, it doesn't look like the aeroboard was installed with delicate precision... looks as if it was droped in sheet by sheet as the wall was built...... Don't want to get a contractor involved yet..... just looking for some feedback on it first...
 
Good!.... From what I can see around the meter box, it doesn't look like the aeroboard was installed with delicate precision... looks as if it was droped in sheet by sheet as the wall was built...... Don't want to get a contractor involved yet..... just looking for some feedback on it first...
I have a 1990 bungalow, same cavity walls and aeroboard. This is what always stops me getting that pumped in extra beads stuff, the aeroboard is definitely not stuck solidly against one wall so I think you'd be doing well to fill all gaps when there could be numerous blockages and of course it's impossible to see in and know how well it was filled.

I had a small extension built couple of years ago and they used the pumped in stuff to do that cavity but it was an empty cavity to start with so easy to ensure it's all filled properly, can't say it behaves any differently to original house walls either.

A friend of mine who had an even newer house had it done expecting great things and zero noticeable effect on the heating of the house. I know it's a huge difference in cost but if I'm doing anything I'll wait until I can afford to externally wrap house, after I win the lotto!
 
Answer is yes, once there is a cavity, you can pump, I had my house done recently, some walls about 50mm others around 100mm with a mix of aeroboard, fixed insulation boards (Kingspan stuff) and nothing in some walls (original house I use, newer part and an extension)

How effective it might be is another question, depends mostly on how diligent the installer is.

If the aerobaord is loose may be less effective
 
@Fisherman

Had similar set up in previous home - '80s bungalow and got the walls pumped. At the time, they drilled a lot of external small holes in the wall & pumped the beads though, forcing the white aeroboard back against the inner leaf wall. I have to assume that it was not uniform all the way around the house, with missing aeroboard / broken areoboard / something between the aeroboard and the wall etc but it did make a difference .

You also need to make sure that the house is not too airtight - you will need ventilation within the house. Have you external vents / window trickle vents for air flow already in place? Any issues with condensation on the windows / mould in the corners of walls at the moment ?

I THINK that as part of the bead insulation, there is a requirement to add ventilation, so that the installers were also drilling through the walls and putting in vents (which kinda negated the heat retention saving of the bead insulation as they were just big holes in the walls). These changes came in after I got my previous home done, but check the recent regulations anyway. I know @Micks'r has posted some great posts on such within AAM, so might be worth a search through the older posts, and get a list of what the company does as part of the bead installation. If you can get your attic insulated - then go for that too (there should also be a grant available for that).
 
Any issues with condensation on the windows / mould in the corners of walls at the moment ?
Walls only thing remaining. Attic, windows, cylinder, all done. Trickle vents in windows . Experience a bit of mould in corner of one bed room, but I know what causes that.... HAIRDRYER..... ( not going down that road!!)
 
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