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
Once fully cured (usually overnight), sand the repair flush with the original wood. Start with 80-grit to shape, finish with 150–220 grit for a smooth surface. repairing a rotted window sill