I have to replace my roof due to a hail storm that came through last year & I thought it would be a cut & dry deal, but it has turned into a headache!
My living room has a vaulted ceiling and the moron that built the house used 2X6 rafters and packed rolled insulation between the sheetrock & the roof decking.
From what I have read I need at least 2" of air space between the decking or I run the risk of moisture build-up and rotten wood.
I first thought about having a roofing contractor pull the decking off during the roof install and put baffles on top up the insulation but then I would have to go with a R-13 because I will only have about 3" of space to work with - I want at least R-30…
I thought that I had a plan but now I’m not sure. Please give advise on the following (other recommendations welcome):
1.) Pull down the drwwall and add a 2X8 to the bottom of the existing rafters to give more room for thicker insulation.(easier said than done).
2.) Remove the drywall and insert baffles to give the 2" air space & then use closed-cell spray foam to fill the remaining 3.5" of space left (I read that closed-cell foam gives a better R value and acts as a vapor barrier) the only problem with this is the spray foam contractor wants $1500 and only wants to spray 1.5" of foam (he say’s 1.5" of foam is better than R-30??? - I don’t buy that???
I hate to be so long with this but I need to make a choice before I get a new roof & I still have not made up my mind what shingles and ridge vent to use! My house currently does not have a ridge vent and it was built in 95 ( another dumb move on the builders part).
Thanks for any help.