5 posts / 0 new
Last post
tzfbird
Insulating attached garage

The walls in my attached garage are finished. Uninsulated but finished. However I would like to insulate the ceiling/roof. I have the large spacing in what I could call trusses which is somewhere in the 32" range. I contemplated adding unfaced bats of insulation to the underside of the roof(directly against roof since the rafters have 16" spacing) but that will only result in being a bad idea.

Do I plan on adding additional trusses so I can finish the ceiling and add insulation since that seems like the correct way to go about it? The final issue I run into is that I have no ventilation in my soffits or roof vent so any summer ventilation is strictly what leaks past the overhead door. I'm not opposed to adding soffit vents, but cutting a hole in a new roof is not high on my list of favorite things to do. Can I add a ridge vent to existing shingles without replacing any?

I'll try to get my technical names for everything corrected so everything makes more sense.

jkirk
Re: Insulating attached garage

for the soffit vents, this is easily solved, you just need a large hole saw to use in a corded drill, drill some holes in the closed soffit in between rafters (look for the nails trough the plywood or boards)from there install perforated vinyl soffit.

for the roof you wont have to remove any shingles but you will have to remove the ridge cap. once thats done snap a chalkin line 2" down from the peak all the way along the roof on both sides stopping 2 ft in from the ends. now cut out the sheathing and shingles with a circular saw along the chalk line but set the depth of the saw blade to the equivalant of the thickness of the shingles and the roof sheathing so to not overcut into the rafters. from there remove the waste sheathing and install the ridge vent.. next put down new ridge cap and your good to go

dj1
Re: Insulating attached garage

Regarding the ridge vent, which jkirk explained correctly, you must follow the instructions precisely, or you'll end up with leaks.

jkirk
Re: Insulating attached garage

i forgot to mention when your finish the new ridge cap there will be one tab which the nails are exposed, pick up a tube of roofing patch which can dab over the exposed nails to seal them

tzfbird
Re: Insulating attached garage

So there's no way around it. I should do it the correct way then. Thanks for the help. I'm going to start picking up my materials as things go on sale and hopefully get this all done in the spring. I am a bit concerned as far as finding tab shingles of the same color. Maybe if I'm extra careful I can take the cap off without much damage since they are new. Just a though but I'm going to try and locate the correct ones first.

I'll be glad when I don't have to wear cover-alls just to change oil in the winter.

I had asked the "roofer" about adding ridge vent and he said it's whatever the "roofers" do. He was just a storm chasing contractor that hires out cheap labor. I could have done a better job on the roof myself with a bit of help, but I could not have got the whole job done in 8 hours as they did(start to finish).

TV Listings

Find TV listings for This Old House and Ask This Old House in your area.