Why spend so much (any) effort insulating the building slab?
I have just enjoyed reading 2-3 years’ worth of blog posts on the site and (Living in Australia) I am intrigued by how much effort and resources (foam) is used to insulate a home’s slab/basement from the ground in some of the high performance builds.
Surely doing this just introduces complexity and opportunity for movement of the slab? Should houses even have basements anymore? They seem like they make it much harder to insulate your building envelope. The only advantage would seem to be if you wanted to utilise the thermal mass of the slab.
Wouldn’t it require less resources and be cheaper to build like in my included diagram? (insulating the building from the slab). This design would allow you to use much cheaper and more environmentally friendly insulation.
Look forward to hearing your thoughts.
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