Interior or exterior insulation for concrete panel walls?
AussieAdrian
| Posted in Green Building Techniques on
I live in Melbourne in 1930s house which is built out of 70mm (2 1/2 inch) thick concrete panels. I could do interior with studs insulation then plaster or exterior with insulation boards that can be rendered over. I’m finding it hard to decide as insulating the exterior I save space inside and have more thermal mass inside, but insulating inside might be better at keeping the heat in in Winter which is more important in my climate. So my question is it better to insulate inside or the outside of the wall?
Thanks, Adrian
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Replies
Adrian,
Exterior insulation is better in all respects. You are much less likely to have thermal bridges with an exterior insulation approach than an interior approach.
That said, you need to pay attention to insulation continuity with either approach. If you install exterior insulation, think about your floor insulation and your ceiling insulation, and strive to connect your wall insulation with the other insulation planes, without any thermal bridges.
And even concrete panel buildings need a continuous air barrier.
Peter
Thanks for the quick and helpful replies.
Now I just have to get the planning permit thru the heritage department.