What to Put on a Windowsill That Is Cracked?

Materials

• One of the most common solutions used for cracked windowsills is epoxy consolidant or primer and epoxy paste filler. Epoxy primer consists of equal parts liquid resin and hardener. The solution penetrates wood and hardens to provide a primed surface for epoxy wood filler. While epoxy consolidant is liquid, epoxy filler has a consistency similar to cookie dough or putty. This allows it to stick and mold itself to the wood so it will adhere to the surface rather than split and crack after drying.

Tools

• Epoxy and consolidant are available at large home repair stores or can be purchased online. In addition to a hammer, putty knife, rasp, drill and wood chisel, you will need sandpaper and a squeeze bottle for dispersing the epoxy solution. Gloves should be worn while applying the epoxy and primer.

Preparation

• Before repairing your damaged windowsill, it needs to be prepped for the epoxy solvents. Remove rotten or decayed wood and old paint using a scraper or fiber brush. Drill holes into the wood to release excess moisture, allowing the wood to breathe and dry. These holes will allow the primer to fill and soak into the wood’s surface. Cover the sill with epoxy consolidant and allow it to sit for a minimum of one week. Cover the sill with loose plastic during rainy weather and uncover during sunny days to quicken the drying process.

Application

• Follow the instructions when mixing the epoxy wood filler. Apply the filler with the putty knife into the sill. Work quickly if the weather is 70 degrees Fahrenheit or warmer since heat hardens epoxy filler quicker. Likewise, cold slows down the hardening process. Use rasps, sandpaper and other sharp tools to smooth and shape the epoxy along the windowsill after it hardens.

Considerations

• Typically, one coat of epoxy filler is sufficient for light repairs. The filler is thick and easily fills cracks if the wood is properly prepped and primed. However, two coats of epoxy filler may be needed to repair large areas. Allow enough time for the first coat to dry before sanding and applying a second coat. To prevent further decay after repairs, maintain the paint and caulk around your windowsills to prevent moisture from saturating the wood. For more serious damage, contact a local building contractor to help pinpoint the issue.