Scope of Protection
An original design of a building embodied in any tangible medium of expression, including a building, architectural plans, or drawings, is subject to copyright protection as an “architectural work” under Section 102 of the Copyright Act, 17 USC, as amended on December 1, 1990. The work includes the overall form as well as the arrangement and composition of spaces and elements in the design but does not include individual standard features or design elements that are functionally required.
The term building means structures that are habitable by humans and intended to be both permanent and stationary, such as houses and office buildings, and other permanent and stationary structures designed for human occupancy, including but not limited to churches, museums, gazebos, and garden pavilions.
Eligible Works
Architectural works created on or after December 1, 1990, and any architectural works that were unconstructed and embodied in unpublished plans or drawings on that date are eligible for protection.
http://www.copyright.gov/circs/circ41.html