Wall vapor barrier for new construction in zone 3A
I’m getting ready to build a 28×40 garage/workshop in Hot Springs Village, AR, climate zone 3A.
Walls will be traditional 2×4 framing with 7/16″ OSB sheathing. Siding will be vinyl to match the house (required by the POA restrictions).
I plan to insulate the walls and ceiling, and also intend to heat/cool the workshop portion of the building with a mini split heat pump.
I plan an underslab vapor barrier ( monolithic slab on grade), but I am unsure about the vapor barrier in the walls.
My questions are, should I use a vapor barrier, or just a traditional permeable air barrier (i.e. tyvek) on the walls? Do I place the vapor barrier on the outside of the sheathing, and use unfaced fiberglass in the walls to allow it to dry to the indoor conditioned space?
Thank you for your help on this.
GBA Detail Library
A collection of one thousand construction details organized by climate and house part