Best exterior insulation options for solid block walls
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I’m looking for a suggestion on the best exterior insulation options. My house is built with poroton blocks (aka porotherm), similar to aerated blocks, the standard here in Italy.
For exterior insulation on this type of wall on a two-storey 2500 sq ft house (foundation is slab on grade) in zone equivalent 3a or 4a (house uninsulated, it’s just got the poroton blocks (30cm) with render and plaster), what material would you recommend in terms of a good value insulation for cost without moisture problems?
I’d prefer to go with a natural option like wood fibre or hemp.
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Replies
If you can get rigid wood fiber and can detail it to be protected from moisture, that would be my first choice. Second choice would be a dense grade of mineral wool, and third choice would be a rigid foam product.