The requirements, guidelines, and standards set forth in this chapter shall apply to any development or redevelopment of property within the zoning districts listed and within the City of Norwalk. Single-family and two-family dwellings are exempted from this chapter, except that all single-family and two-family dwellings, including manufactured homes and factory-built homes, and accessory structures including detached garages and sheds over 120 square feet in size, shall be residential in character and must incorporate Class 1, Class 2, Class 3, or Class 4 materials on 100% of their façade area.