Rain Water Coming Through Expansion Gap in OSB
Unit : Detached garage
Location of problem : exterior wall
Current project : insulating garage
Scenario: ok so hopefully you have an idea of the setting I want to use a combo of fiberglass wall batts and for smaller areas in the framing use canned spray foam. So for starters there is some type of lining between the framing and the sheathing similar to the thickness and flexibility of sand paper that was not affixed to the osb overlapping in the cavities in some areas allowing wind to come through so I Applied dynafles 230 sealing/caulk and applied flashing tape to try and make it a continuous barrier. I did this while I was inside the garage and not knowing any better I also filled the expansion gap between the osb which now I know is not a good idea but thats where all the outside wind was coming through. I let that sit and cure over night the next day I put up about (9) wall fiberglass batts and filled in 2 other narrower cavities with some expanding foam and again let that cure over night. And that brings us to today. It rained for the majority of the day and after work I came back to the garage to finish the insulation and found that the majority of the wall batts I installed were wet at the bottom and notice water around the footboard. Now, luckily the batts are not completely ruined but it just sucks knowing that all that progress was for nothing.
So I begin drying the wet area and will have a fan run over night to hopefully take care of the rest of the water.
Where I think I went wrong was filling the expansion gap of the osb
with the spray foam and the tape. I did notice water dripping from the tape in some areas.. what do i do? Should I undo everything ? Won’t water rot out the osb and footboard if more water continues to seep through? Do I have to take off siding and replace weather barrier? Can I just apply caulking to cracks on the outside siding to stop the rain from getting in. This darn garage getting pretty drafty. I probably have enough material to do this project 4 times but I’d rather not do that and at this point I rather just finish and hire outside help. thanks again for taking on this question and I hope to get this project done soon. Probaky bes t to maybe do. Video call so I can show you. Let me knownand happy new year!
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