Best Way to Clean Composite Deck

by Paul Bianchina

landlord helpQ: Any suggestions on cleaning a composite deck material? I have two decks finished with composite decking and I have notice black dots forming after only one year. Also, can composite decks be sealed or need to be sealed? –John M.

A: For routine cleaning of a composite deck, just use soap and water. I would suggest a powdered detergent with a degreaser, such as Spic and Span, mixed with warm water, and applied with a nylon scrub brush or push broom. Rinse with cold water.

You can also apply the soap and then do the rinsing with a pressure washer set on a wide fan spray. Stubborn spots should come clean by mixing up a paste of water and detergent and scrubbing with a nylon brush.

The tiny black dots you are seeing are probably mildew, which is not uncommon. There are now several deck cleaners formulated specifically for use on composite decks, and many of them say that they’ll take care of mildew problems.

Before doing that, however, if you know the manufacturer of the decking material I would either check out their website or give them a call and ask for their specific recommendations for dealing with mildew.

And no, composite decks should not be sealed.

Remodeling and repair questions? E-mail Paul at [email protected]. All product reviews are based on the author’s actual testing of free review samples provided by the manufacturers.
Copyright 2010 Inman News

See Paul Bianchina’s feature, Common Heating Systems Compared.

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