Hello!
We are about to lay flooring in the newly expanded part of our house. I've planned the following construction:
Tiles
Self-leveling compound
Underfloor heating
Chipboard
Wood fiber insulation
XPS
Outdoor air-ventilated crawl space/ventilated foundation
Ground plastic
This felt obvious until I realized that there might be double vapor barriers. My idea is that the XPS boards should be installed completely tight and thus act as a vapor and diffusion barrier, keeping the rest of the floor structure warm and dry with the underfloor heating.
The question is whether the self-leveling compound is too dense? I've tried googling but found nothing interesting. Will the self-leveling compound and tiles let through enough to avoid moisture problems?
This expansion also includes a bathroom and laundry room. How about there? Are the waterproofing layers open enough for diffusion?
