When wood furniture is damaged by water, it requires restorative care to ensure that it remains strong and functional. Not only does water stain wood, but it also sometimes leaves behind toxic mold and mildew that needs to be removed promptly. Clean the mold off the furniture first, then repair and restore it.
Put on disposable plastic gloves. If the furniture has mold and mildew, take it outside to clean. Mix two caps full of bleach with half a bucket of warm water. Add 3 caps full of mild liquid dish-washing detergent. Stir the liquid with a stick. Dip a scrub brush into the bucket. Scrub the furniture thoroughly. Wash off the soap with a garden hose, and repeat if necessary. Let the furniture air dry.
Try to remove water stains with wood furniture cleaner. Apply the cleaner to a soft white cloth. Mix a few drops of orange oil in with the cleaner, and rub it onto the furniture in a circular motion. Repeat this until the stain lifts. If the wood cleaner and orange oil don't work, try mayonnaise or salad oil dressing in place of them. Clean the wood with a soft cloth. Remove any excess mayonnaise or salad oil with wood cleaner.
Sand the furniture with an electric sander if the stain is not easily removed. Use a sander with 220-grit sandpaper. Open the windows for proper ventilation, and seal off air-conditioning ducts. Put on a dust mask to keep yourself from inhaling wood dust.
Sand the furniture in the direction of the grain. Sand the water-damaged areas first. Remove wood dust with a clean paintbrush, and continue sanding the remainder of the furniture to even out the finish. Again remove wood dust with the paintbrush.
Strip the furniture with a chemical stripping agent. Stripping is the easiest way to remove deep-set stains without removing layers of wood. Dip a clean paintbrush into the chemical stripping agent, and apply it to the surface of the furniture in smooth strokes. Wait for the chemical agent to oxidize, or begin to bubble.
Take a scraping tool such as a putty knife and scrape the surface of the furniture. After stripping it, sand the furniture with 100- to 150- grit sandpaper to remove excess stripping agent. Remove wood dust with a paintbrush.
Glue loose joints on the furniture with wood glue. Remove old glue by sanding inside the joints with rolled-up 150-grit sandpaper. Remove wood dust with a paintbrush. Place glue inside the joint, and reattach the table or chair leg. Put a clamp on the joint and let the glue dry overnight. Use epoxy wood glue for hard-to-glue sections such as the corners of dresser drawers, or decorative sections that require reattachment of intricate, raised wood.
Stain or paint the wood furniture once it is repaired. Use a waterproof stain, and apply it in even strokes with a clean paintbrush. If you're painting the furniture, use latex enamel-based paint in the color of your choice. Apply two coats of stain or paint. Let the first coat dry before applying the second.
Choose a clear varnish that is both waterproof and insect repellent. After the furniture is dry, apply two coats of varnish with a clean paintbrush, letting the first coat dry before applying the second one.