Closet over garage insulation and air flow problem?
I have a house that was built in the early 70s, and there is a long roof run (first picture) that goes from the first level over the garage up to a peak over a second story bedroom. The closet I am building is over the garage (I installed R30 insulation in space between garage ceiling and floor of closet) and the bedroom is over a family room that sits behind the garage on the first floor. The closet is built into unheated storage area with sheetrock covering walls and sloped ceiling with R13 insulation everywhere outside of new closet.
I basically split the store room in half with a wall, removed the sheetrock and r13 from the half section of the store room and built a closet area (second picture) that does have a heat vent. The roof Rafters are 9in and I installed r-30 kraft faced insulation with baffles (third picture) to allow air flow. I also built a 54in knee wall with 6in studs and added are 19 insulation. The house is in Maryland and during my recent work the temperature went down to the single digits during which I had completed the work and install drywall on the sloped ceiling.
The problem is that condensation built up in the area between the insulation/baffles and the roof sheathing and I found it when I pulled down some of the insulation to do a bit of work. The unique property of the roof Rafters going from the first floor garage up over the second-story bedroom in the back presents a challenge. I could have spray foam, closed-cell, sprayed in but I'm not sure if that would work because I would be essentially stopping air flow from the soffit over the garage up to and out the Attic. I would assume the condensation came from a combination of the bedroom and the rest of the storeroom that, well unheated is probably getting some transfer of heat and moisture both from the garage below and the door from the bedroom to the store room.
My question is if there is a way to adequately insulate the new closet ceiling that I can prevent condensation buildup? Moisture can come from three different places, the bedroom, the store room and from what it naturally would pull from the soffit over the garage. And as I stated earlier, I am concerned about stopping the flow of air from the soffit over the garage up past the closet to the attic over the bedroom and vent out. I am not sure if I'm fighting a losing battle here. Thank you in advance for any assistance.