Radiant and slab insulation
I have 8″ of structural floor depth to play with in my new addition. The engineer specd 6″ slab leaving me 2″.
So essentially I can do:
2″ insulation then 6″ slab with embedded pex
OR
No insulation, 6″ slab, thermal break then 2″ gypcrete.
I am leaning towards option 2 since the area I live in is cool but mild (never below freezing) and I like the idea of having a responsive system where I can turn down a few degrees at night. However gas is also very expensive where I live, so my primary concern is overall efficiency. What’s the better setup for my use case and are there other factors I’m forgetting?
What insulation/thermal breaks should I be looking at to maximize efficiency?
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Replies
What thermal break do you have in mind? Does a basement slab need to be responsive?
I assume you are talking about a structural slab? Not sure what climate zone you are in, but your slab should be insulated from the earth below, and insulated at the exposed sides. Some engineers will insulate below the footing portion, some will not.