Are you up to Fire Code on that building? Since it is connected to your home.
Code specifications would be great if given. And what code specs did you go by or did you overkill on the codes? Overkill on codes is a great thing.
Thats a good question.... probably not up to code exactly. The shed sits on an external slab backed up to the exterior of the house which is cement board (deem as a non-combustible material). We also have a nest protect in there for fire/smoke warnings. In fact it went off last night I think because there was a fire somewhere outside (you could smell it) and the fresh air intake brought some in.
Just a warning, google recalled a lot of nest. Becareful, man. Hope you live by yourself and not with children, wife & pets or putting someones life at risk including yours.
http://www.informationweek.com/cloud/software-as-a-service/googles-nest-recalls-smoke-detector/d/d-id/1269110Only recalled because of the wave to dismiss option.