u/SGP_MikeF

I have return vents in these walls which is between the garage and the living room. Sheet metal is in both sides of the current drywall where return cavities are. I already had an HVAC guy make sure the whole thing is air sealed from the garage. Obviously since the area is being used as an open cavity, there’s no insulation in the circled area.

My current plan is to frame out a second wall on top of the existing wall from the garage side then add 5/drywall on top of that.

The main concern I have is mold that could form between garage wall and new second set of garage drywall. Does anyone have recommendations on best type of insulation?

Do I need a vapor barrier on either existing or new garage drywall? It does look like the current living room side has one. (Cold climate - Nebraska)

Termites? Carpenter Ants? Pavement Ants?

This is in an unconditioned sunroom on a slab. Behind it is the living room, where I’m not seeing anything. Below the living room is a utility room, with some exposure to the backside of the CBU right here (behind the wood trim is a wood panel, behind that is CBU/cinderblock). I’m not seeing anything there either.

I’ve been reading alot of these posts. The most recent got me a bit worried on mine.

It goes up about two feet, then extends 4-5 feet, then combines into the HVAC vent. The near horizontal slope has me worried. Is it okay?

It looks like a permit was pulled in 2022 with the old homeowners by a licensed plumber. It’s unclear if it was ultimately issued.

Thoughts? Okay? Not okay?