Page 1 of 1

Insulating Cantilever

Posted: Sat Oct 14, 2017 2:15 am
by mikeyitis
I had previously made a post about insulating my unconditioned garage ceiling. Now I have one more question before I get started and it involves insulating a cantilever with a conditioned space above and the unconditioned garage space that is below. I attached pictures for reference.

2.png (508.4 KiB) Viewed 184 times
garage_insulation.jpg (54.44 KiB) Viewed 184 times
As you can see in picture 1, there is no plywood or barrier between the joists and the aluminum soffit, it is just the aluminum soffit by itself. Is this ok or does there absolutely need to be a wood board or other barrier in-between the aluminum and the joists? Can I just insulate it by using the method in picture 2 or is there a better method that you would recommend? Would I seal off the joist area directly above the stud wall with insulation board like it is shown in picture 2 or would I leave that open since the garage space is unconditioned and I am only insulating the garage ceiling for the space above?

Re: Insulating Cantilever

Posted: Sat Oct 14, 2017 6:20 am
by Shannon
My first instinct is that it needs plywood to keep critters out (small bugs and such) but it is likely not really any different then a normal vented soffit which gives access to critters to the insulated attic ? So I guess really it does not need any plywood.
I would do it just like picture #2

Re: Insulating Cantilever

Posted: Sat Oct 14, 2017 8:21 am
by mikeyitis
Thanks for the advice.