Mold is a general term used for fungal growth. It will grow on just about any exterior surface including decks. Wood is not naturally resistant to mold infiltration. Even pressure treated pine will get mold on it if the conditions are right. Most decks have seen their fair share of mold depending on climate, humidity, and sun exposure. Shaded areas of decks are typically more prone than sunny areas. Even some deck stains can be more prone to mold than others.
Mold and wood do not mix. Mold will win every time. Spore infiltration may be surface mold or it could go deeper into the wood fibers. Damage can range from unsightly appearance to major structural damage. The good news is that mold on decks can be removed safely before damage is done. Most decks should be cleaned and re-stained every year or two to keep a maintained appearance. Regular maintenance will increase the deck’s longevity. Knowing how to remove mold on decks does not include any big secrets. If you follow a general cleaning method you will remove mold in the process.
A deck should be cleaned using a quality wood cleaner. Most cleaners will have specific cleaning directions. Most commonly a wood cleaner is used with a pressure washer or scrub brush to remove common dirt, grime, graying, and yes MOLD! After removing mold on decks it is then best to apply a deck stain that has mold and mildew resistant properties. Most of the deck stains that fight off mold and fungal growth are formulated with zinc oxide pigments and mildewcides. Do your research before settling on a particle deck stain.
NOTE: The mold that grows on decks is different than the mold that you may hear about growing in walls or basements that can be very dangerous to humans. Those types of black mold spores usually need to be professionally removed by a certified remediation company and differ from the mold that grows on a deck or the north side of a tree. It is not suggested to touch or handle the mold on a deck but washing it off with a pressure washer will not cause you harm. It will, however, harm the wood if left alone.
