I am following Building Science for finishing my basement (16' X 40', 3 outside walls). For my walls, I am using 2" XPS and 2x4 Stud walls with mineral wool insulation, and then drywall.
For the floor, I am putting 1" XPS on the concrete, and Advantech 3/4" T&G OSB subfloor. Not decided about finished floor, but leaning inexpensive laminate.
Two questions on the flooring:
- The laminate says to put a 6mil vapor barrier under it, but the approach for building science is to dry to the inside, so no vapor barrier. What to do there?
- With the 1" XPS directly on the concrete floor, if there is any moisture, there is no where for it to go. Looking at dricore design, they have
the 'normal' product (a membrane panel under osb), it leaves airflow to allow release of the moisture... and the R+ product (with XPS under the osb), but the XPS is 'slotted' on the bottom, I suppose also similarly for airflow.
Should I also cut slots in the bottom of my 1" XPS, both directions as they did, to allow for breathing?
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