How To Repair Stone Window Sills [better] May 2026

Stone window sills are the unsung heroes of a building’s façade. They bear the brunt of rain runoff, UV exposure, and physical impact. When they crack, spall (flake), or erode, water penetrates the wall cavity below, leading to rot, mold, and structural damage. Repairing them promptly is not cosmetic—it’s protective.