Rotten windowsills may cause damage to the interior of your home by allowing rainwater to enter the home. If an exterior windowsill on your home contains rotten wood, you may wish to repair the wood. Repairing a rotten windowsill enhances the curb appeal of your home. A windowsill is located on the exterior of your home on the bottom of your window frame. When selecting your paint for the windowsill replacement select paint color matching the existing color other windowsills. Here’s how to repair window rot.
Galvanized finishing nails
Remove the rotted windowsill with your hammer and chisel. If the windowsill does not remove, gently separate it from the rest of the window with your pry bar. You may wish to cut the nails holding your windowsill in place with a hacksaw blade.
Place the old windowsill on top of the new windowsill wood and trace the cutout from the old stock with your pencil.
Cut out the traced wood on the new windowsill stock with your jig saw.
Sand the new sill with your sandpaper, rounding the cut edges. Apply a wood sealer to the new seal with your paintbrush. This helps preserve the new sill from water and weather.
Place the new windowsill on the bottom of your window in its designated area. Secure the new windowsill with galvanized finishing nails and your hammer.
Countersink the nails heads with your nail punch. Place the nail punch over a nail head and gently tap the nail punch with your hammer until the nail head sinks into the wood of the windowsill. Repeat for each nail.
Fill the nail holes with wood putty according to the manufacturer’s instructions. Select wood putty close to the color of your wood. Allow wood putty to dry and sand with sand paper.
Fill any gaps on your wooden windowsill with paintable exterior caulking and your caulking gun. Allow the caulking to dry according to the manufacturer’s instructions.
Prime and paint the wooden windowsill with primer, exterior paint and your paintbrush.