attached garage vapor barrier

[ducter]

have a new house in NC ,2car attached garage with just the walls that are connected to the living area finished with sheetrock and vapor barrier towards the interior rooms sides...pretty standard.

I want to sheetrock and insulate the rest of the garage to make it more pleasing and comfortable. I will only use a small portable heater once in a and maybe a protable AC unit. This will be an occasinal handyman workshop and garage. Should I use a vapor barrier toward the inside of the garage on the rest of the bare walls or none at all since I will only use heat and AC once in a while? This would mean that the vapor barrier is on the garage side on some walls and towards the room side on the existing finished wall.

I also have a large closet /room off a bedroom on the second floor that is also unfinished (attic above) that I would like to do the same with. It is 9*15 and just studs with insulation and vapor barrier on the wall that is connected to the bedroom. Dont know if I would /should heat&cool it but want sheetrock. should I just move the insulation adn VB to the walls in the closet and sheetrock? I know that typically a closet isnt heat and cooled but this is a large closet / room and dont want any mold issues. I could run a duct there to just temper the air.

[homebild]

Moisture and mold is not a problem for unconditioned spaces.

As long as the area remains at the ambient outdoor temperature most of the time, there is no temperature differential, and therfore no potential for condensation and moisture/mold to occur.

For temporarily heated or cooled areas, do nothing.

Especially if they are vented to the outside as are attics or some crawlspaces.

[ducter]

I guess that I will instulate it with the batts that are faced because it sounds like it cant hurt. I already have the insulation with kraft paper so I am only worried that using a vapor barrier would cause some harm?

Also the garage ceiing was insulated and sheetrocked because a bonus room is above, except for 2 ft on the right and left of the garage ceiling, that was not insulated (but is rocked) because that is actually small areas of the attic. do you think that instead of ripping out some of the garage ceiing to insulate, I would be able to just lay blankets on the osb floor where the small attic areas are above? Is having the insulation here just as good?

[Under_Miner]

I guess that I will instulate it with the batts that are faced because it sounds like it cant hurt. I already have the insulation with kraft paper so I am only worried that using a vapor barrier would cause some harm?

Also the garage ceiing was insulated and sheetrocked because a bonus room is above, except for 2 ft on the right and left of the garage ceiling, that was not insulated (but is rocked) because that is actually small areas of the attic. do you think that instead of ripping out some of the garage ceiing to insulate, I would be able to just lay blankets on the osb floor where the small attic areas are above? Is having the insulation here just as good?
Yes this would work just fine, keep in mind, though that you must maintain ventilation as you would with any other attic space. As far as vapor barrier, it is not required if the adjacent space is heated. Moisture will tend to form on the warm side of the wall when the moisture in the warm air condensates on the cool wall, In this case the garage will be cooler than the adjacent space, thus making any vapor barrier on the garage side useless.