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totoblue
8th June 2007, 04:29 PM
Anyone know an easy way to retrofit wall insulation to a weatherboard house?

We have a weatherboard house, some of which has foil insulation and some of which doesn't. The foil that is there is pretty daggy and probably doesn't keep out the moisture reliably.

Short of pulling off all the plaster inside the exterior walls, or pulling off weatherboards, the only way I can see of insulating the walls is to use something that can be injected via a small hole.

Having used expanding foam for other purposes, that would seem dodgey and likely to bow the walls and/or leave gaps. So is there a non expanding foam that can be used? It would need to be a reasonable price, not wick moisture, and be electrically ok.

I suppose some of the blow-in products might be an alternative, if the hole required is not very large. My guess is that they'd be more likely to wick moisture if there was no foil.

I know you can access some of the inside of exterior walls by removing roof tiles and blowing in insulation, but that only gets you down to the noggin. Which is probably better than nothing, as the top half of the wall would likely lose more heat than the bottom half, because hot air rises. However the lower half of the outside of the wall probably gets colder so it might balance out.

rhancock
9th June 2007, 10:47 PM
Back home in the uk, they used to drill a hole in double skin brick cavity walls and blow in polystyrene beads. They'd use a gadget to find cold spots and just drill another hole where the beads haven't filled.

totoblue
11th June 2007, 02:27 PM
Back home in the uk, they used to drill a hole in double skin brick cavity walls and blow in polystyrene beads.

Thanks. I did some research and the use of beads is discussed here (along with other methods for retrofitting).

http://www.greenhouse.gov.au/yourhome/technical/fs16a.htm

totoblue
12th June 2007, 04:09 AM
This week's episode of "This Old House" on Lifestyle channel (paytv) showed them using slow-pour foam to insulate inside the walls of a stucco house (quite similar construction to a weatherboard house).

http://www.thisoldhouse.com/toh/knowhow/heatingcooling/article/0,16417,1575422,00.html

Lozza
18th July 2007, 07:17 PM
the company that is able to supply a pump-in foam for retrofit applications just like this is Foamed Insulations Pty Ltd. Contact them on 02-9898-0751. The product is called RetroFoam and you can also go the the manufacturers website www.retrofoam.com (http://www.retrofoam.com) for more info.

MarkWags
2nd August 2007, 11:52 AM
Thanks for ther advice. Do you think this will have any effect on the timber boards. I saw another post that was saying you should use foil bats with holes in otherwise you could damage the weatherboards (sweating perhaps?). Surely, this foam would have the same effect or perhaps worse?

thanks

Lozza
6th August 2007, 10:27 AM
Hi,

the foam should have no effect on the timber boards. once the walls are insulated, you should not have any sweating on the inside of the rooms as the wall surface temp should remain above dew point. is that what you meant?

cheers
loz

Amb
13th August 2007, 10:31 PM
With any of these prodcuts, where you pump/inject/spray some sort of insulation into your stud wall cavity, I'd be concerned about any effects on the electrical wiring, particularly in an old weatherboard house. Maybe nothing to worry about, but I'd check with some of the experts on this site.

totoblue
20th August 2007, 05:09 PM
the company that is able to supply a pump-in foam for retrofit applications just like this is Foamed Insulations Pty Ltd. Contact them on 02-9898-0751

They've got a website at
http://www.foamedinsulations.com.au/