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Can Base of Wall Flashing Trap Water

Nat_T | Posted in General Questions on

In construction, new build, zip-r sheathing on concrete basement walls.

I’m sheathed and plan on liquid flashing the base of my sheathing to the basement wall soon. We had a bit of rain the other day and I see areas on the exterior basement wall concrete where water that landed on my deck made it’s way under the wall plate, down the rim joist, and outside. It got me thinking that eventually when I have some big spill inside (washing machine failure, kids science experiment gone wrong, etc) that water would follow a similar path but get trapped in the rim joist/sheathing/flashing pocket and live there.

Unreasonable concern? caulk all of my interior wall plates well and hope it forms a dam against future spills?

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  1. Expert Member
    Peter Engle | | #1

    You should caulk the interiors of the wall plates anyhow as an enhancement to your air barrier. Beyond that, don't worry about it, and clean up spills when they happen.

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