Foam Board Insulation Under Slab
Hi there, we’re working on a remodel (Climate zone 4-marine) and will be leveling our basement floor by primarily pouring new concrete over existing concrete. In some areas of the basement we’ll have 4″ of new concrete.
Are we able to meaningfully improve the heat loss of our basement by installing some rigid foam insulation in between the two concrete layers (above existing and at base of new concrete)?
Architect says its only worth doing if we were to cover the full floor with foam board (which isn’t an option if we don’t demo the whole bacement floor) – is that accurate?
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