Insulation in joist cavity with limited access
I just moved into a house built in 2003. I’m in the process of removing the fiberglass insulation placed in the basement by the builder, to be replaced by foam (tbd sheets vs closed cell spray). This is in anticipation of finishing the basement. I’m in a northern Canadian metropolitan area, Zone 7A.
My question is regarding one area of the basement, where an engineered joist placed lengthwise along the interior edge of the concrete wall is blocking access to the rim joist cavity — Cross sectional attached. From a few holes through this joist for utilities (gas line, AC, plumbing and drain into exterior wall above), it appears that the cavity was pre-filled with fiberglass insulation during construction.
I’m not sure how to approach this with regards to sealing it off properly to prevent condensation and mold growth.
I’m waiting to hear back from Weyerhauser regarding spacing of holes; maybe I punch some holes and remove the fiberglass to provide access for spray foam, but I don’t know if they can be spaced close enough.
Would appreciate all thoughts and advice.
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