My "she-shed" was labeled "the workroom". Same thing, We enclosed the double car garage and installed a wall unit A/C. Loved the space, but one downside was that it was detached from the house. I had to walk outside to get there, and it grew to be inconvenient! It didn't bother me at first, just when the "newness" wore off. My advice would be to attach your workroom to the house; it would also solve the isolation feeling.