In our area, any addition that doubles the ft2 of the building, or remodel of more than 50% requires an update of the existing structure.

Requiring a structure to be upgraded after a vacancy? If that's the law, it's only because nobody's retained a lawyer and gone before the building and zoning board yet...

Where most of the upgrades of structures like the one in question come up is actually from banks / mortgagers, who'll refuse to finance a house that isn't at least 100A.

[This message has been edited by DougW (edited 04-03-2005).]