Insulating a basement that HAD a moisture problem
1910’s Colonial in Climate Zone 5….
I am dealing with a basement that HAD a moisture problem. This past September, perimeter basement trench (French) drains and new sumps were installed. We have gone through several rounds of significant rain and snow melt, and the basement is dry as a bone. The moisture issue has been dealt with.
What, now, is the preferred method of insulating the basement walls? Closed cell spray foam?
XPS? Poly-iso boards? Do I want some sort of drainage mat against the wall behind the insulation?
It must be noted that we will also be insulating exterior balloon framed walls and properly air sealing/insulating the attic in the process of this home performance retrofit. We are expecting to significantly tighten the envelope through the course of this project.
My inclination is CCSF in the basement, but I wonder if it is too vapor impermeable and if that will too drastically inhibit drying to the inside.
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