should i install vapor barrier between attic living space and garage?

A vapor barrier in the wrong place will create condensation, moisture and mold problems, which is much more serious than a seasonal heat differential. Make sure that the vapor barrier is on the side of the insulation that is TOWARD the living space, which is where the water vapor comes from. That way, the moisture will not penetrate the insulation. If the barrier is on the cold side of the insulation, then water vapor gets into the insulation and finds the dew point somewhere on the way to the cold side and condenses.

Feels like you could have obtained more going on than only a somewhat bigger humidity stage within the crawl area..... A normal vapor barrier is only a layer of plastic which prevents moisture from visiting through it. 6 mil plastic works simply satisfactory, and can be discovered at any hardware store. Seal or overlap the joints (by means of a couple of foot), and penetrations. There are merchandise made for instances the place you need a stiffer plastic membrane, like if you find yourself pouring a concrete flooring, or basis/wall. One such product is called "Plenom". This product just isn't wanted over a traditional crawlspace ground.... That is what you possibly can put below the concrete before it's poured. There are some other considerations right here too.... Do you've a principal air drain, or clothes dryer vent that run into the crawlspace? If so, strolling those to the oustide of the crawlspace will support relatively slightly. You would be amazed how so much moisture is created through just those two. Cross air flow is also primary to prevent moisture construct up. Consider free to electronic mail me, with details, and might be i will present some more distinct recommendation. Just right luck

A vapor barrier goes between a climate-controlled area and one that is not. A vapor barrier has no effect on heating costs (the insulation does).

Nick's right. A vapor barrier will keep out condensation and inhibit mold growth to the floor joists, insulation, and subfloor, and water damage to the garage ceiling, especially if you have plumbing or ductwork running through that space.