Weeks and Day was an American architectural firm founded in 1916 by architect Charles Peter Weeks (1870–1928) and engineer William Peyton Day (1886–1966). Weeks was born in Copley, Ohio, educated in the atelier of Victor Laloux at the École des Beaux-Arts from 1892 to 1895, and briefly partnered with John Galen Howard. (Weeks is unrelated to the Canadian-American architect W. H. Weeks, also practicing in San Francisco in these years, and is also unrelated to William E. Weeks, architect in Southern California. ) Day had been in partnership with pioneering San Francisco reinforced concrete engineer John B. Leonard. With Weeks as designer and Day as engineer, the firm specialized in theaters and cinemas, including several exuberant movie palaces and hotels in the San Francisco Bay Area, extending to Los Angeles and San Diego. The firm was most active immediately before Weeks' death in 1928. Day continued the firm for 25 more years, closing the firm in 1953.

Architectural work