Preventing mold and mildew growth on composite decking

Thursday, October 29, 2009 by Chris Fox

Mold and mildew can be a nuisance on any exterior building surface, regardless of the material. If the conditions are right, they will spawn on wood, plastic, concrete, metal and other surfaces. Mold formation is most prevalent in consistently wet, shaded areas. Spores from the natural environment are carried by the wind and commonly land on decks surfaces. It is important to note that the appearance of mold and mildew is a function of nature, not necessarily a deficiency with any of the material on which it grows.

Deck Cleaning
Periodic washing with soap/detergent and water will help remove surface dirt. This will also help prevent the buildup of pollen, debris and spores that can cause and accelerate mold/mildew growth (it also helps to remove deck mold). Caution: A pressure washer should not be used to “blast” mold/mildew or soils from a deck surface. The abrasive nature of the water stream can potentially damage the material by driving the spores into the material, which may create a moreMold on composite deck before/after cleaningchallenging problem to remediate. A pressure washer with a fan-tipped nozzle should be used only to lightly wet or rinse wood or composite deck surfaces. 

There are many deck wash and exterior cleaning products available at retail. It is important to make sure you use a cleaner specifically intended for your application. After selecting a product, be certain to read, understand and follow all instructions supplied by the manufacturer. Some cleaning products and inhibitors may be more effective than others, depending on the environmental conditions your deck is subjected to. Additionally, it is always a good idea to test the cleaner in a small, inconspicuous area prior to applying it to the entire deck.

Mold Inhibitors
As with deck washes, there are several mold-inhibitor products available from paint stores, hardware stores, online outlets and home centers to help prevent long-term mold/mildew growth. For any product selected, be certain to read, understand and follow all instructions provided by the manufacturer. Depending upon the environmental factors affecting your composite lumber or treated wood deck, some preventive cleaning products may be more effective than others. It may be necessary to try more than one product. For ongoing preventive maintenance, follow the manufacturer’s recommendation.

Common deck cleaning chemicals

Friday, May 1, 2009 by Chris Fox
Whether cleaning pressure treated wood decking or synthetic / composite decking material, many of the same cleaning agents are effective on both surface types.

Many deck wash/cleaners contain sodium percarbonate and a detergent, which works well on normal dirt and grime and bleaches out mold and mildew stains. An oxygen bleach-based formula is another great alternative. It's effective in removing mildew stains and the weathered grey residue from UV (sunlight) degradation. Both cleaners are environmentally safe and will not harm plants or animals, damage wood's cell structure or leave a bleached-out look.

Oxalic acid cleaners are effective on rust stains left from metal furniture.

Commercial degreasers contain propylene glycol, sodium hydroxide, and various detergents for removing grease and oil stains.

Spot removers/thinners can be used sparingly on particularly stubborn grease or oil stains, but should be washed off quickly with water as they will attack the grain pattern. These normally include petroleum distillates, xylene, methanol, acetone, or other organic solvents.

Maintain your deck with periodic washing

Friday, April 17, 2009 by Chris Fox
Decks are a wonderful place to entertain family and friends. They provide added 
outdoor living space
and can increase the value of your Periodic washing helps maintain pressure treated deckingproperty. Maintaining your treated wood deck will save you money in the long run. And having your deck cleaned periodically is very impoProWood Micro pressure-treated lumberrtant to its beauty and longevity.

Some wood decks need to be cleaned more often than others. If your treated deck is in a shady area under trees, where mildew and mold are know to thrive, you’ll probably need to clean it once a year. If you do encounter excessive mildew or mold on your deck, be sure to apply an inhibitor to help alleviate buildup.