Bees nest in shed...I think.

I think I have a bees nest in my shed. They seem to be going into a crack between the roof and the front of shed above the door. They may be wasps but I don't think so.
If they are bees I don't mind but wonder how long they will be active. I didn't have the nerve to stick my head in the door and look up and wonder how big the nest will be?
I usually just lean in and grab tools so I can live with them being there.
Any info appreciated.