Garage Insulation

DIYguy2000

We live in a town house with attached garage (sandwiched between two other houses). The garage is always very cold compared to the rest of the house and I wanted to add insulation to maybe help with inside heating costs, but also for doing some handy work in there. The walls between the inside of our house and the garage are insulated, but the garage door and exterior walls are not insulated. Most of the drywalled ceiling is insulated (bedroom above), but the front 4' or so are not as there is a roof above it (2nd floor bedroom is setback 4' from front of garage face). When I saw this I decided to cut a few small holes in the wall that I share with the neighbors garage. All I see is my drywall, 2 rows of 2x4 stud wall, and the back face of his drywall. Considering his garage will also not be insulated either, what are my options here?

I already put up insulation on the exterior walls (front of garage [around door]) and put on vapor barrier.

I'm also putting up rigid foam insulation on the garage door itself, and weather stripping, likely the main source for the cold.

Will all this work make a difference, or will that 20' un-insulated wall between our two garages and the 4' of un-insulated ceiling come back and bite me?

I know you can rent (or hire pros to do the work) the insulation blowing machines from Home Depot, but is it worth it to fill 20' of 2x8 wall shared between me and my neighbor? What about the 4' section of ceiling?

Is that even to code (Ontario, Canada) not to have more of a fire barrier between the two units other than two sheets of drywall?

On a side note, when taping vapor barrier, do you only tape cut seams, or do you have to do edges as well (i.e., when the vapor barrier reaches the 2x6's the garage door rails and garage door opener are mounted to? I plan on putting up drywall once I figure this question out.


Thanks for all your help!

Scuba_Dave

If drywall is the only thing between your garage & your neighbors I would insulate
Same thing with the 4' space - it will let cold air in
Myself I'd be a little concerned that there is only drywall between the garages
I'd want some plywood sheathing to prevent someone from breaking into your garage from the neighbors
Probably not a big deal as long as neighbors leave the garage door closed

DIYguy2000

I never thought about security, thanks for the tip. They are an older couple, usually at home, and leave their door shut all the time. We always keep the inside door between the garage and house locked. I'm not too concerned, buy definitely worthwhile knowing about! Thanks for the tip!

Do you require vapor barrier on blown insulation?

What prep work is required for blown insulation into the attic space? (no access, unless I cut a hole in my ceiling)

Anyone know how much it would cost (roughly) to rent a blowing machine and the cost of the insulation? ceiling to be insulated 4' by 9', wall to be insulated 20' x 8' x 7" (double 2x4 stud wall).

Thanks for the help!