Window replacement costs in Charleston

Charleston has a written policy for replacement windows. In December 2025, both panels of the city's Board of Architectural Review adopted it for the Old and Historic District, the Old City District, the Landmark Overlay Zone and the Historic Corridor District. It applies to work visible from a public right-of-way, and it bans vinyl and vinyl components. Wholesale replacement needs the board's approval. If you want to replace rather than repair, you have to show why, with photos and a window schedule that labels every window on all four sides of the house.

For a house 50 or more years old in the Old and Historic or Old City districts, the policy points to wood windows with true divided lites, matched to what's there. Newer houses in those districts get more choices, including aluminum-clad wood and steel. Preservation staff make the final call case by case.

The building permit asks its own questions. If your permit runs through Charleston County's Building Inspection Services, its window form asks for four things: the design pressure rating, the type of windborne debris protection and how it's fastened, the U-factor and the solar heat gain coefficient. Under the 2009 energy code the county cites, that means a U-factor no higher than 0.50 and a solar rating no higher than 0.30. The county's form says that rule applies when some or all of a window is replaced, sash and glass included.