Things You'll Need
Baking soda
Toothpaste
Cup
Rag
Furniture polish
Utility knife
Small flathead screwdriver
Medium and fine sandpaper
Epoxy primer
Brush
Wood epoxy filler
Putty knife
Primer and paint
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Over time, if a windowsill is not correctly shielded from the natural elements, or if a wet mug is simply set down without a coaster, the sill will deteriorate or rot. A water-damaged window sill can, however, be brought back to its best with a minimum of knowledge or know-how. Restoring a sill ranges from the application of toothpaste and baking soda for water stains to the more labor-intensive process of repairing rotting wood with epoxy primer and wood filler.
Water Marks
Step 1
Mix together in a cup a 50/50 solution of baking soda and toothpaste.
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Step 2
Rub the mixture gently over the water mark with a rag. Wait a few minutes before rubbing in more of the solution. Do this as many times as needed until the water mark disappears.
Step 3
Remove all solution, wait for the area to thoroughly dry, and apply furniture polish.
Severe Damage, Including Rotting Wood
Step 1
Scrape off all paint and damaged wood from the area--use a utility knife and small flathead screwdriver. Thoroughly sand the area as well as the edges of any holes. Remove all dust and wood particles.
Step 2
Apply a thin layer of wood epoxy primer to the damaged area with a brush. Wait 10 minutes for it to dry.
Step 3
Stir the wood epoxy filler and apply it to the damaged area, using a putty knife. Wait for it to dry and sand the area with medium and fine sandpaper until smooth to the touch.
Step 4
Prime and paint the sill to seal it from any future weather/water damage.
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