Home Forums General Discussion What is the best way to insulate walls without removing the wall panels? Reply To: What is the best way to insulate walls without removing the wall panels?

Paul Hansen

Kia ora people,

In my experiance in the trade, when asked to look at doing walls as part of a complete package for people in a retrofit scenario I always stressed the following.

The ceiling and under floor will make the biggest differnce. So therefore tackle these areas first and do them well and upgrade the ceiling by as high an R-value as the budget allows (ie by several points over the minimum standard).

Then sit the first winter out and judge the difference made in house warmth. The cost of retro fitting walls, unless part of a general make over/maintenance where the wall lining will be coming off anyway, is probably similar or higher than doing both the ceiling & under floor combined. Once the key hole install is finished then you still need to make good the holes in the wall linings , paint etc.

It will be hit and miss to a degree as you won’t get a keyhole into every stud/nog space.

Yes, polystyrene does react with the white outer coating on your electrical wiring and you are meant to use a purple coated electrical cable to negate this issue (this has been around in the NZ market for some time, guessing at 10-15 years) so most retro fitting will not be into this type of cable coating.

90% plus clients were happy with the result from the under floor and HIGH R-VALUE CEILING to not bother with getting into the walls until a general reno was about to occur.

I would also contend that the next area to tackle at a cheaper budget cost would be air ingress from leaking joinery and interior/exterior claddings, disused open fire place chimney’s (a virtual high pressure vacuum of house warmth!) and the lovely topic of down lights also sucking out heated air.

ka kite

Paul Hansen