Hope for help! Untreated wood on concrete at doors’ rough openings
Slab on grade shop with those doors’ rough opening framed and untreated (UT) wood extending all the way down (covered by Tyvek in pics) to interface with concrete slab, which will be used for our finished floor with epoxy coating (only seal sill between UT wood and concrete. With water coming in/out from foot/vehicle traffic as well as if floor is hosed down, I am concerned that with no pressure treated (PT) wood between concrete and UT wood that mold and/or rot will occur. During one rain before roofed, staining did occur on one of the bottoms. Two options I am wondering if you can help with and/or any other ideas, we just aren’t going to redo framing completely.
1) Replace last 1 1/2″ with PT wood pieces and somehow squeeze some new sill seal in with it underneath. (someone suggested just replace sill seal with felt roofing paper like they used to instead of replacing last 1 1/2″ with PT wood; however, I’m concerned that won’t really work to keep waterproof and/or water off if it)
2) Extend a waterproof vapor open tape down exterior (as well as interior) side at Tyvek/concrete stem wall interface and then around bottom floor location where UT wood/concrete slab interface.
(For man door sills, will be applying Dupont’s Flexwrap NF from back of sill down over face 2-3″ but that still won’t address interior UT wood/concrete slab floor interface. And I am not seeing this as a good option for large garage door opening sill.)
* Also, any ideas how to do this entirely differently from the start on the new slab on grade house we will be building.
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