We recently purchased a ~50 years old house in the SF bay area. The roof is >20 years old, wood shake, we expect to replace it in a couple years. There is minimal attic ventilation: a few holes drilled in the eaves and gables. There is also minimal insulation: 2-3 inches of loose cellulose. I'd like to do what I can to improve these for energy efficiency and to keep the house cooler in summer.
I've talked to two roofers; one suggested installing additional inlet vents between the rafters (we have open eaves), plus a couple outlet turbines; the other said the shake roof will breathe so he didn't see the point in doing anything now. Any opinions on who is right?
I'd like to bump up the insulation to R30. We have a few old recessed can lights, I can't easily determine if they are IC rated hence they probably are not. Would it be wise for me to replace these with IC rated cans, or just ensure that the insulation doesn't contact them?
For insulation material, we've gotten quotes for blown fiberglass. Once you've installed a thick layer of this, it seems to me that attic access is going to be a huge pain in the ass, right? I'm thinking that we should do any other attic work -- like installing bathroom vents -- first, for this reason. Or, is it not a big deal to move the stuff around after it is in place?
It seems to me that the insulation is the first priority; ventilation won't prolong the life of the roof, and the insulation will make the biggest difference in keeping the house warm/cool. Am I right? On the other hand, if it will be much easier to do the eave vents before the insulation is installed, that would be a good reason to do that now, if we'll need them later (say if we get a composite roof).
-- Dave