Footprint: The entire area of ground covered by the structure(s) on a lot, including but not limited to cantilevered or similar overhanging extensions, as well as attached structures such as garages, decks, porches or steps.
The terms "expansion," "enlargement," and "extension" shall, for the purposes of these standards, be synonymous and shall mean any increase in the footprint covered by an existing nonconforming use or any increase in any dimension of a nonconforming structure, including height.
94-412 C.M.R. ch. 107, § 2