Construction Guide · Charleston Metro, SC

Wind- and Impact-Rated Windows: South Carolina Coastal Building Code Requirements

Glazing on a coastal build is a code question before it's a design one. Homes in a wind-borne debris region must protect every opening, and fixing that late costs more than planning ahead. A few points are worth clarifying before specs go out.

Confirm which code edition governs your permit

South Carolina currently builds on the 2021 IBC and IRC family, adopted statewide by the LLR Building Codes Council. A 2024 cycle update has already cleared public comment, so the edition governing your permit may differ from last year's. Confirm the currently adopted edition in writing with your architect or official.

Design wind speed is a site question, not a metro number

Industry sources often place Charleston-area jurisdictions in a 130 to 150 mph range, but the actual figure shifts with distance from the coast, risk category, and the ASCE 7 edition in effect. Charleston County keeps its own wind-zone map for that reason. Pull the applicable number from current LLR maps or a site study, and confirm with whichever municipality holds jurisdiction, since local amendments vary.

Impact glazing and shutters solve it differently

Openings need impact-resistant glazing or an approved covering, tested to ASTM E1996 and E1886, with large-missile performance below 30 feet and small-missile above it. Impact windows ask nothing of the homeowner once a storm nears; shutters require deployment every time. Costs vary widely by size and installer, so price both against your opening schedule.

Weighing impact glazing against shutter systems for your next coastal build? Contact Chris Eller directly.