Drywall Gap At Concrete Basement Floor – Caulk Or Other ?
stuartd
| Posted in General Questions on
Climate Zone 6 House
Prior to baseboard installation, is there anything that should or can be installed for air, sound, or other reasons at the 1″ or so gap between the bottom edge of the 5/8″ drywall, and the insulated concrete walk out basement floor? The finished floor will probably be vinyl planks. The bottom plate already has the foam sill sealer sandwich, and the three exterior above-grade walls have CONTEGA SOLIDO IQ tape (exterior / mud sill joint).
Attached photo is of an area in a bathroom, thus the purple drywall)
Thanks
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Replies
You could vacuum out the drywall dirt in that gap and fill the cap with canned foam, or just let the baseboard cover it. It's not super critical unless you need to seal that gap as part of your air sealing.
Bill
Deleted
Thanks
Coincidentally, Matt Risinger just posted that he uses Sashco Lexel in this gap.
https://www.youtube.com/watch?v=IMpbafn_55g
I do have a large leftover supply of Siga Fentrim IS 20 tape, which was also way less expensive than tubes of Lexel. What do you think about using it to bridge the gap (it normally connects concrete to wood mudsill, but since I now have drywall, my application would be concrete to drywall (and of course there would be air space remaining, as opposed to caulk or foam which would fill that void.
stuartd,
If the primary air-barrier is the exterior, sealing the gap is perhaps good practice, but not particularly important. Tape will work fine. The gap itself is of no consequence.
I think the gap between the concrete and the drywall is a desirable feature.
The gap prevents moisture from wicking up into the drywall lowering the risk of rot and mold.
The gap between the drywall and the basement floor does not seem like the prime location to focus your air sealing efforts.
Walta
In situations where the wall does NOT contain framing with a sealed bottom plate, such as a foundation/rigid foam/drywall sandwich , this would be a critical air-sealing (or radon-sealing) crack. Here, I agree it's a waste of time and material to fill it.