[nmchick]

Hi there. I have an adobe garage with metal roof and wood rafters. Want to insulate under the roof (interior) with eco-friendly easy to use material (batts but not fiberglass?). Should I put something (water barrier) against the metal roof first before laying in insulation? Any suggestions on kind of R38 insulation to use. Rafters are 4" so lots of the insulation seems like it would be thicker than the rafters. Then need to put drywall over that? Want to finish off with rolls of bamboo poles for an island feel. Thanks for any suggestions, including 'just get a contractor'.

 

[Just Bill]

Sounds like foam would work well here. But have a pro do it. Depending on the climate, you might need open or closed cell foam.

 

[Paragon]

nmchick,

Just get a contractor!

Okay not so funny I know.

I responded fairly extensively to a posting regarding attic insulation a while back and here is the link http://www.diychatroom.com/f19/furring-rafter-bonus-room-47199/. So check it out if you get a chance.

If you only have 2x4's for framing then you are at a further loss as you only have 3.5 inches of framing and will only achieve an r value at most of R. You will have to add framing to the structure to get a deeper cavity and achieve the r value of 30 or more (depending on where you are at here is a link for you to identify the r value for your specific geographical location http://www.ornl.gov/sci/roofs+walls/insulation/fig2.html )

If I were you I would contact a contractor and have them take a look at the project and talk you through the project unless you are looking to tackle this project yourself however there are a couple factors there that may be a challenge for a homeowner to tackle themselves.

Good luck and be safe and I didn't mean to pull the contractor card but if you can handle it yourself go for it.