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Correcting WRB and Sheathing Issue

pico_project | Posted in General Questions on

Two issues I noticed today on our remodel. 

When clearing out some plants on the north side of the house I noticed one corner was not fully covered by the WRB (Siga Mavjest 500 SA).

This brought up another issue. The previous sheathing was 3/4″ Celotex. The replacement sheathing is 1/2″ plywood — so we currently have a 1/4″ lip where the sheathing meets the block.

90% of the house the WRB is set correctly and kicks out a little over the top of the block, so I haven’t given it much thought. However, this exposed area got me thinking that we should definitely seal this connection better.

Would liquid flash be appropriate to use here on top of the WRB and onto the block? We also have Siga Fentrim tape we used for the windows. The issue I had with the tape is that it couldn’t be easily counter-flashed. Any other ideas on how to address this?

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  1. Expert Member

    Those surfaces look fairly smooth. I’d think you would be fine installing the finetrim and having a reverse lap joint. So long as you roll it well and don’t have any fish mouths, I don’t see a water problem happening.

    1. pico_project | | #2

      Thank you for the feedback. For future reference do you know if liquid flashings can be applied over a SA WRB like Mavjest?

      1. Expert Member

        I'm uncertain, but the words fluid, liquid, and flashing never appear in any combination in their data sheets / tech docs that I could find. Maybe if you sent them an email they'd have more advice.

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