Insulating garage with open celing

[ssntmre]

Hello, I am working on a total remodel of my garage this year. I was wondering how difficult it would be to insulate the open rafters of my garage. I do not want to build a celing because I plan on installing a lift and need the height. I have basically an open celing to the peak of the roof, the same as a barn instead of having a metal roof i have a regular shingle celing. Is there an easy way to get some kind of insulation up there and not run the risk of rotting the roof or cooking the shingles? Not looking to make it airtight just a little more comfrontable. I saw some insulation board at Lowes and was wondering if i could just screw it to the bottom of the trusses. It would leave an airspace if i did that. would that be okay? I am really a novice in construction and insulation, However I could post picks if that would help... thank you

 

[buzz4041]

Insulation board of 3/4" will give you R5. That stuff is supposed to be covered by fire rated drywall so you have some protection for it. It will help but make sure you don't block off the air flow from the soffit to exhaust. I actualy have used this exact material under my roof on my whole house along with full soffit venting and the temperatures dropped around 20 degrees in the attic. Airflow is a key element though.

 

[headwrench]

just use 2in thick styrofoam on the trusses. a little more R value plus its white so no painting & it will reflect the light. used it in my shop & it works great. my .o2

 

[svtrichie]

I have the same problem. I talked to a company that told me to to spray foam on the underside of the roof. I didn't get a price yet since I am a little unsure on it.

 

[marcello7x]

After i have my roofing redone i will be looking into this as well. Im in the same exact situation being that my garage is an old barn converted over. I want to keep as much loft space as possible.

 

[The J]

ssntmre: Is the roof portion vented or is the whole garage non-vented?

I just started a very similar thread, so we may be looking for the same info. Mine's an unvented garage that I'm looking to insulate.
http://www.garagejournal.com/forum/showthread.php?t=138130