Insulating a hutch

ive got a double wall on my hutch so to leave a space between to insulate... i was told i could put foil in and then bubble wrap rather than buying the proper stuff, but is that right?

I wouldn't advise using bubble wrap in the cavity as it will stop the wood from "breathing" and lead to condensation and mould. If you hutch is doubleskinned, like mine, then the samll space between has an insulating effect any. You're better just to cram the hutch full of hay.