Eric, welcome aboard the good ship VAF
There aint no such things as "big enough" when talking hangars.
45X35....... try to keep from from building a "T" hangar. The corners come in very handy
My advice is build as big as you can afford as I've never heard anyone complain their hangar was too big.
Regarding BCs and such. I forget dimensions but in jurisdiction I was looking (rural VA County) above a certain size (maybe 50x50 or so) you were required to have commercial sprinkler system installed, etc.
My advice is build as big as you can afford as I've never heard anyone complain their hangar was too big. If your plane gets lonely I'm sure it can invite friends over for sleepovers.
We negotiated a 3600 sq ft limit that can have a reduced residential sprinkler system, any larger and a full commercial sprinkler system is needed.
The discussions went on for a long time...
If you have a full flow fire hydrant nearby you probably don't need sprinklers.
The fire hydrant is on my lot, less than 300' from the proposed house and hangar.