To be patentable, the object must be new, useful and non-obvious. The newness standard requires that the invention has not have been publicly disclosed prior to the filing date of the patent application (with limited exceptions). The usefulness standard requires that it has a use, which should not be a problem with architectural designs (except for certain “post-modern” designs). The non-obviousness standard requires that one of ordinary skill in the art (architecture in this case) would not have been motivated to combine prior art references (e.g. existing buildings and publications) to achieve the claimed building. The question of non-obviousness involves a complex legal analysis, which requires the advice of a patent attorney.
For example, US Patent 8,371,073 protects a building with integrated systems that reduce dependency on external resources; US Patent 2,172,838 protects a slanted building with an offset arrangement of successive stories; and US Patent 3,866,363 protects a wind energy dissipating building.
Similarly, utility patents can protect functional elements associated with a building, such as lighting systems (e.g., US Patent 8,172,435), bio-retention basins (e.g., US Patent 8,834,066) and window covering head rail cornices (e.g., US Patent 5,042,548). US Patent 8,336,261 protects an entire revolving roof for a stadium.