Publication date: 06/26/2004

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The right chemicals will help safely brighten your deck

It's not your fault if your deck looks a little ratty. It was too wet to take care of the deck last summer and we had a tough winter.

No matter how eager you are, be sure the deck is dry at least three continuous days before cleaning, brightening and sealing. Wet wood is weak wood. Washing a wet deck with a pressure washer can severely damage the already weakened wood.

Since chemicals do most of the work, pressure washing isn't required to clean, brighten and strip a deck. All that is needed are the proper chemicals, a good deck brush, and a garden hose.

If you are perplexed about what to do, you are not alone. Deck care is such an "easy" task that Wolman Wood Care Products has 125 pages of instructions and technical information on their Web site. The Flood Co., another organization that takes its job seriously, has 96 pages of instructions.

I know the numbers because my staff printed them out and counted them. In total, we printed out more than a ream of paper doing research for these deck-care articles (so much for the paperless society).

General cleaning

If the deck is just dirty, use a simple organic cleaning solution such as Sunshine Makers Simple Green or Westley's Clear Magic by Pennzoil-Quaker State. For light dirt, use 1 part cleaner to 10 parts water. Medium dirty requires 1 part of cleaner to 4 parts of water. Very dirty decks require 1/2 gallon of cleaner to 1 gallon of water.

Dull gray and mildewed decks

Wood left out in the sun turns gray as the UV (ultra violet) rays kill the outer layer of cells. For years, the standard way to "brighten" the deck was to add 1/2 gallon of household bleach to a solution of 4 ounces of TSP and 2 gallons of water. This mixture cleaned, brightened and killed off mold and mildew.

Unfortunately, bleach is hazardous to plants, animals and people. Bleach is used in the paper industry to break down lignin, the natural component that holds wood together. It does the same thing on your deck. In fact, it does so much damage to the outer layer of wood that it can no longer absorb stain evenly.

Common household bleach is a 3 to 6 percent solution of sodium hypochlorite in water. The same ingredient is in many deck cleaners including Cabot Problem Solver Wood Cleaner, Behr No. 62- Multi-Surface Deck-Prep & Mildew Stain Remover, Thompsons Deck Wash and Armor-All EZ Deck Wash.

If you do not want to use a bleach-based product, use a mild acid such as oxalic, phosphate or citric acid, or disodium percarbonate (often advertised as oxygen bleach). Both cleaners are also good at removing tannin and rust stains.

Found naturally in asparagus, broccoli, cabbage and carrots, oxalic acid (wood bleach) is the most commonly used acid on deck wood. You will find it in BEHR Wood Brightener Conditioner No. 63, Flood Dekswood, Cabot Problem-Solver Wood Brightener No. 8003, and Wolman Deck & Fence Brightener for Cedar & Redwood. You can also buy it in granular form at many hardware stores or on the Web at www.chemistrystore.com.

Phosphoric acid is used as an antioxidant in food and as a flavor agent in jellies. Products based on this very gentle ingredient are Bio-Wash Simple Wash and Penofin Weatherblaster.

Citric acid was first isolated in lemon juice and is found in most plants. Probably the gentlest of the wood brighteners, it is used on fine cedar, redwood and hardwood decks. Coronado Maxum-Prep Wood Brightener contains citric acid. You also could buy it in concentrated form at www.chemistrystore.com.

Disodium percarbonate (oxygen bleach) is a very environmentally friendly cleaning/brightening agent. It comes as a powder and has to be mixed fresh each time it is used. Oxygen bleach is especially good on pressure-treated pine, hemlock and fir. It is also recommended for hardwoods such as oak, maple and poplar. Wolman Deck & Fence Brightener and Expert Cleaning Solutions, (800) 262-5710, and Wood Brightener Plus are based on disodium percarbonate.

According to Al Abruzzese, a home improvement contractor who hosts Al's home improvement center on the Web, you already might have disodium percarbonate. It is the active ingredient in laundry cleaners such as SC Johnson's Shout Oxy Power, OrangeGlow International Oxiclean, Clorox Oxygen Action, and Lever Brothers All Oxi-active.

If you wanted to make your deck cleaner, you could use the product you probably already have in the laundry room or buy disodium percarbonate on the web at Al's Home Improvement Center, http://alsnet biz.com/homeimprovement/oxybleach.html or at www.chemistrystore.com.

After reading Abruzzese's article on oxygen bleach, my publisher used 3 ounces of TSP and 3 ounces of Oxiclean in a gallon of hot water to clean a heavily mildewed portion of our test deck on Memorial Day. It took some scrubbing, but the wood, which had turned green with mildew, went back to its natural color. I'm not willing to make this combination a deck cleaning recommendation, but it worked on our test deck. If you have the time, you might want to experiment, develop your own secret deck cleaning formula, and brag about the result.

If you have a question, call Glenn Haege's Handyman radio shows at (866) ASK GLENN. The shows run noon-2 p.m. Monday through Friday on WXDX-AM (1310) and 8 a.m. to noon Saturday and Sunday on WDFN-AM (1130) and on 150 other stations nationwide. To suggest a question for his Thursday "Ask Glenn" column, write: Ask Glenn, Master Handyman Press, P.O. Box 1498, Royal Oak, MI 48068-1498 or e-mail: askglenn@masterhandy man.com.

Note: This article was accurate at the date of publication. However, information contained in it may have changed. If you plan to use the information contained herein for any purpose, verification of its continued accuracy is your responsibility.

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