How to install insulation

[FarmerSid]

Hey all! I'm about to start insulating my shop I built this summer. I have a full second story above the shop for storage and such. The second floor is made up of 5/8" T&G plywood on top of 2X10 floor joists. I plan on heating the down stairs but not upstairs. So when I insulate the ceiling in the shop should I completely fill the space between the joists or do I need an air space? I plan on using batts of insulation. I was thinking of putting in a layer of 2X6 insulation and then another layer of 2X4 insulation to fill the space. What should I do?

Cheers!

Sid

 

[cw_racefan]

Rather than "2x6" then "2x4" insulation, simply use R-30, which is already 9 1/2 inches, will fit perfectly with your 2x10 joists.

 

[FarmerSid]

Ahhhhhhhh! Didn't realize I could get insulation that size. None of my suppliers even suggested that. Thanks for the info!

Cheers!

Sid

 

[cw_racefan]

No problem! Only reason I knew is because I'm getting ready to insulate mine also! And ouch, is that stuff $$ to do 1100 sq ft!