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Community and Q&A

Basement Finishing

KLBe | Posted in Building Code Questions on

Hi there, I am finishing my basement as a DYI. I don’t have a lot of money for the project, so I can’t hire anyone to help and I can’t pull a permit for the task. I need to know if the following will be an acceptable build.

1. I have glued up .5 inch polyiso board insulation
2. I have 2×2 furring strips that I intent to install on top of the polyiso board by drilling through the wood, foam board, and poured concrete then fastening with 2.5-inch masonry screws (fasteners)
3. Thereafter, I will be putting up wood paneling

I do not have a hammer drill so I purchased rotary drill masonry bits for the job. I do have a construction nail gun with 2.5″ nails.

My other questions:
1. I intend to glue down a 2×2 strip to the floor using construction glue. There is already one on the top attached to the joists. Then I intend to nail the vertical strips to the floor strip to secure them. Should I instead fasten them to the concrete floor?

2. I just had waterproofing done due to footing leakage and there is white corrugated plastic running along the base of the wall to allow any wall moisture to drain into the newly installed foot drains. Can I put the polyiso board right over the top of those?

3. Can I just use my nail gun to attach the furring strips to the concrete? Will that work? Do I need special nails?

4. Does all of this meet regulation for Michigan and if not, what else do I need to do?

I’ve recently had beams put up because one wall is bowing and they put some sort of roll sheet insulation/water vapor over the cracks that they repaired. Is this polyiso sheeting? I’ve attached a few photos of it and I’ve attached a photo of the wall that I put up the polyiso .5-inch boards. 

Thank you so much for your time and answers.

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  1. user-2310254 | | #1


    Insulation requirements are climate dependent. You should read this article before starting your project:

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