Md. Code, Pub. Util. § 7-401

(a) In this subtitle the following words have the meanings indicated. (b) “B.T.U.” means a British Thermal Unit which is the quantity of heat required to raise the temperature of 1 pound of water 1 degree Fahrenheit. (c) “Builder” means: (1) the person with whom the owner of a building enters into a contract or agreement to be principally responsible for the construction of the building, either individually or as a general contractor; or (2) the owner of a building, if the owner constructs the building or serves as the owner’s own general contractor. (d) (1) “Building” means any new structure that: (i) is designed for human use or occupancy; (ii) provides a method of controlling energy usage within its exterior envelope; and (iii) as designed, does not have a peak design rate of energy usage per square foot of floor area of less than 3.5 B.T.U. per hour or 1 watt. (2) “Building” includes any portion of an otherwise excluded new structure if that portion of the structure is primarily for human use or occupancy because the exterior envelopes, heating, venting and air conditioning systems, service water heating, and electrical distribution and illuminating systems are designed for that portion of the structure that is primarily for human use or occupancy. (3) “Building” does not include: (i) an addition to an existing structure or a single-family dwelling that is to constitute the principal residence of the builder; (ii) a structure with a permanent heating and cooling system that utilizes a source other than natural gas, a petroleum product, or electricity; (iii) an industrialized building as defined in § 12-301 of the Public Safety Article that bears an insignia furnished by the Department of Housing and Community Development under Title 12, Subtitle 3 of the Public Safety Article; and (iv) a manufactured home as defined in § 12-301 of the Public Safety Article that bears an insignia issued by the Department of Housing and Community Development under Title 12, Subtitle 3 of the Public Safety Article. (e) “Energy Code” means energy conservation standards adopted under COMAR 05.02.07.04 Maryland Building Performance Standards (MBPS) under the authority of Title 12, Subtitle 5 of the Public Safety Article. (f) “Political subdivision” means a county, Baltimore City, or a municipal corporation.