Repairing a rotted window sill is a common home maintenance task that can prevent thousands of dollars in structural damage if caught early. While it may seem daunting, most localized rot can be fixed with a few specialized tools and materials like high-performance epoxy or wood hardeners. Before starting, determine if the sill is salvageable. How to Repair Dry Rot in a Window Sill
Brush a penetrating wood hardener onto the exposed solid wood. This strengthens the remaining fibers and helps the filler bond. Let it cure per manufacturer instructions (usually 2–4 hours). repairing a rotted window sill