What is the 80% rule for insurance?

The 80% rule means you must insure your home for at least 80% of its replacement cost, or claims get prorated. Waterfront rebuild cost runs 20-40% above the Horry County assessed value. A Pawleys Island house assessed at $600K can carry a $900K rebuild once you factor wind-rated framing, impact-rated shingles, and coastal labor. If dwelling coverage sits below 80% of that number, a $40K roof claim might pay $28K. Reprice replacement cost every two years. Your South Carolina coastal wind insurer (SCWHUA) policy must match the homeowners replacement value, or you create a gap on the highest-risk peril.