Distinguished for its architectural diversity, aesthetically pleasing hues and durability, wood is prevalent in home interiors and exteriors. Whether indoors or outdoors, wood inevitably becomes dingy with dust and grime. Besides appearing unsightly, dirty wood trim and woodwork require thorough cleaning before painting, staining or varnishing. Washing wood with trisodium phosphate allows paint, stain or varnish to adhere to wood. Unlike furniture sprays, TSP is a powerful cleaner and degreaser formulated to detach stubborn gunk, grease and mildew from painted and unpainted wood.

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Well-maintained woodwork lasts for decades.

Step 1

Don goggles and rubber gloves for protection from the TSP. Cover any nearby flooring, if indoors, with plastic sheeting. Provide the same protection for vegetation if you'll be cleaning outdoors.

Step 2

Mix 1 gallon of warm water with 1/4 cup of TSP in a bucket using a wood stir stick. Fill another bucket with warm water.

Step 3

Dip a soft sponge in the TSP solution. Slowly wipe a 2-by-2-foot area of the wood with the sponge to detach ground-in grime. Clean from the bottom of the wooden surface upward.

Step 4

Drench another soft sponge in the warm water. Squeeze the wet sponge and wipe it over the 2-by-2-foot area of wood in one pass, fully rinsing the wood.

Step 5

Clean additional 2-by-2-foot sections until all of the wood is clean. Refill the buckets as the solution and water become dirty.

Step 6

Dry the wood with a microfiber towel.