Understanding Rim Joists
I hope these are appropriate questions for this forum.
1) Is it okay to use pressure treated lumber for rim joists? I’ve seen mixed recommendations and comments about shrinkage. But, all else the same, I’d sure like the extra protection.
2) My floor joists extend completely on top of the foundation walls such that the rim joist (nailed or structurally screwed to the outside edges of the floor joists) would not be supported underneath (and not be supporting anything on top of them). My understanding is that rim joists are solely for the purpose of providing lateral support for the floor joists (so they don’t tip over or move closer/farther from each other). If that is correct, then unsupported rim joists are fine, right?
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