Mystery Structure in Basement
In the process of airsealing/insulating my rim joists and basement. I have one room with a finished Ceiling which I’ve been taking down to access the rim joists. I’ve also had a cement structure outside the house that I didn’t know was actually the roof to to a small part of the entry way to the semi finished (also the 1950s addition) part of my basement. I took down the ceiling and realized there was only 1 inch thick boards. The cement can be seen between these boards when looking up. Any clue as to why it was built like this? The back part of the house is an addition. There did appear to be a small but present water mark on some of the wood trim in that area. I have never seen water on the wall in that area however. Will plan to insulate that but what else should I do? There is flashing present at the siding.
zone 5, 1600sq ft bungalow.
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