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Will insulating my basement cinder block wall cause freeze thaw crack/ issues in the foundation

MikeSG | Posted in Energy Efficiency and Durability on

Hi All,

My name is mike and I live in detroit, Michigan (Zone 6a). I am currently planning on remodeling my basement and would like some advice regarding insulation. My house was built in 1951 and I believe it is a cinder block foundation (though it seems pretty solid when I drill through it) My plan was to put 2in rigid foam insulation then wood studs on top of that and finally drywall. The top 15in or so of the cinder block foundation is above ground behind bricks. I am debating if I should put insulation at all. I am worried that insulating the inside of the basement will cause the cinder block to freeze and then crack during freeze thaw cycles. It can get below zero here in the winter. I am also worried that capillary action may get moisture up to the rim joist if I insulate since it cannot dry to the inside. My contractor is advising me not to insulatefor moisture and freeze thaw issues. Can I get some help with the following questions as I am unsure and do not want to create more issues than solving (in panic mode). I have included images of my cinder blocks wall. Despite what the photo shows, the walls are dry. I am not sure what those dark areas are but the wall feels very dry.. Also, from the top view of the qall it seems there are no voids in the block so not sure of it is cinder block. I have also included the unpainted block for clarity. Thanks in advance.

1. Can anyone help me verify that this is cinder block from the images provided or is it possible that it’s  concrete block (top view of wall looks solid so not sure)?
2. Will insulating the basement cause foundation cracks due to freeze thaw cycles?

3. Will I get any issues with capillary action from the cinder block foundation to rim joist (I do jot have a capillary break in between)?
4.  Since it is cost prohibitive to insulate from the exterior, would you recommend water proofing (dry lock or ames rubber paint) from the inside prior to insulating?
4. Any advice would be appreciated.

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