Christian McArdle wrote:

However, the room you describe will be costing you a fortune if you ever
turn that radiator on. You should, perhaps, think about insulating and
draught proofing anyway.

Eventually, I'd like to turn the garage, which is quite large, into
self-contained living quarters for visiting family - so it _will_ be
insulated and draught-proofed someday.

I think the radiator was put there by the previous owner to keep his dogs
comfortable - they were working dogs, not pampered pets. He was a
gamekeeper, and also kept a few sheep (not in the garage!).

Sheila