Installing recessed cabinets in knee wall. How to insulate?

[Chris S]

I am planning on installing recessed cabinets in my knee wall above my garage. The room is heated/cooled by HVAC. Currently, the knee wall has insulation bats in it. After installing the boxes, I was going to crawl in behind the knee wall and try to attach bats to the cabinets. Any other suggestions? Should I even worry about doing this? I am doing two cabinets approx. 4'x4'. Just to add, I'm a little freaky about heat loss and keeping my utility bill down.

[Stytooner]

I would just get a couple sheets of the rigid foam and stick them to the back and sides of the box. Top too. That would be much simpler. They have it in two" thick sheets. Not sure the R value at that thickness, but you could double it up.
It would be like an ice chest of sorts.

[pelligrini]

+1 on the rigid sheets. I think it would be the easier route. It comes in many thicknesses, and stacking thinner sheets is doable. Most of the pink & blue stuff delivers an R value of ~5.3 per inch