Asked by: Kennedy Faulwasser
home and garden home improvement

What causes mold on decks?

Last Updated: 13th April, 2020

Mold may also be called mildew. It is caused by microorganisms that float through the air daily. Mold can be first identified on a deck when the spores that float in the air land on the deck, find a suitable living environment, and produce more spores, changing colors as they do so.

Click to see full answer.

Similarly, how do I stop mold growing on my deck?

Deck mildew can be prevented if you wash the deck regularly with a special homemade solution. Mix together a bucket of water with one cup of bleach per gallon. To that add vinegar and baking soda. Use a mop to clean the deck with the solution.

Secondly, how do I keep my deck from turning green? The Spruce also recommends cleaning green patios with a homemade solution of vinegar and Borax. After hosing down your patio — either with a pressure washer or garden hose — combine 1/2 cup part distilled white vinegar and 1/2 cup Borax in warm water and place the mixture into a spray bottle.

Just so, why is my deck molding?

Mold that appears on the ground below the deck is a sign one of thing only: too much moisture. It is possible for mold and mildew to accumulate below the deck because it was built too close to the ground, but it's more likely that water and moisture are accumulating there because of improper drainage or faulty grading.

Does Thompson Water Seal prevent mold?

This protection includes: Water repellency, prevents water damage, maintains natural wood grain, all while resisting mold growth. Thompson's® WaterSeal® claim to fame is the ability to waterproof your exterior wood.

Related Question Answers

Amatallah Opgenvorth


Is bleach or vinegar better to kill mold?

Bleach and vinegar can both kill mold, but vinegar is much more effective for removing mold from porous materials. This is because bleach only kills mold spores on the surface of affected materials. Vinegar will penetrate porous materials and kill the mold at the roots.

Yerson Arcaute


Will vinegar kill mold?

White vinegar is a mild acid that is known to kill roughly 82 percent of mold species, and it can even help prevent mold outbreaks in the future. Pour plain, white distilled vinegar into a spray bottle. Because mold is such a resilient force, it's best not to dilute the vinegar.

Nelli Gasymov


Will bleach stop wood rot?

To treat decay fungi, first eliminate the source of moisture (unless its dry rot). A dilute bleach spray will kill molds and mildew. If decay is extensive, replace the decayed wood. However, if lumber is allowed to soak in the wood preservative, it works even better.

Yazara Slater


What kills mold on wood?

Scrub the surface mold stains from walls and wood trim with a mixture of 1 qt. water and 1/2 cup bleach mold cleaner to kill the mold. Use a soft brush and work until signs of the mold disappear. After scrubbing the surfaces, simply allow the bleach solution to continue to penetrate the surfaces and dry.

Mahjoub Berecoechea


How do I stop algae on my deck?

After cleaning a wood deck, the surface should be recoated with a protective deck stain. Composite decks can also be protected with the proper sealer. To prevent mold from reoccurring you can use a product called Wet and Forget. This product can prevent mold, mildew, lichen, and algae from appearing.

Gessami Ward


How do you get rid of mold on a wood deck?

Oxygen bleach is a blend of hydrogen peroxide and soda-ash. It's one of the "greenest" products you can use to clean mold spores. Just mix up the magic formula as per the manufacturer's directions and put it on the deck using a scrubbing brush. Finish up by rinsing your deck with a hose.

Connie Bosmans


Can I use bleach on my deck?

Unfortunately, decks are often susceptible to dirt and algae because they're outside. Contrary to popular belief, chlorine bleach is not a great cleaner for a wood deck. Luckily, you can use powdered oxygen bleach to scrub down and clean your deck without damaging the deck's wood or any surrounding plantlife.

Ibon Glenn


Should I pressure wash my deck?

Often a pressure-washer can effectively clean a deck with just plain water. But a pressure washer can ruin your deck if it's not used properly. If you use it with too much jet pressure or place the tip too close to the surface of your deck, you can deeply etch the wood and cause the fibers to splinter.

Nafisa Krischer


Can you paint over mold?

Painting over mold is one of the most common methods to hide mold. But that is the problem – you are only hiding the mold temporarily. Painting over mold does not remediate the problem. The paint will not kill the mold, and it will only hide it for a short period of time.

Ruthe Sechtling


What do you put under moisture on a deck?

Sloping Bricks or Cement. The soil under your deck will soak up as much water as it can, but when it becomes saturated, the water pools. Prevent this by laying bricks or pouring cement under the deck. This area should slope away from your home, allowing the water to easily run off into the rest of your yard.

Zhonghua Bezruchenkov


How do you get rid of fungus on a deck?

Scrub and Rinse the Deck
Then, using the scrub brush and bleach solution that you just made, scrub the surface of the deck thoroughly. Allow the bleach solution to set in for about 15 to 30 minutes. This will begin to kill the algae and fungus that have developed on your decks surface.

Mingliang Nappo


How do you get rid of a musty smell under a deck?

A few solutions:
  1. Baking soda: Sprinkle it over the areas, then sweep with a broom, making sure it fills in grooves of wood and in between deck boards.
  2. Vinegar mixed with water: Spray or dip a rag or brush in a bucket of the solution and scrub the deck.

Humberta Koukal


Do you have to stain a deck after power washing?

It is not recommended to stain a wet deck. You should remove the old stain before pressure washing the decking to ensure the new one has a good surface to stick to. Puddles of detergent can damage and discolour the wood. Let the deck dry for at least 48-72 hours before staining.

Liselotte Haggiag


Does Trex decking get mold?

Trex, a popular manufacturer of composite decking, says mold will not damage the deck boards.

Randee Cenitagoia


Does vinegar kill algae on decks?

Vinegar is a good option as it will remove mildew, mold, and dirt on the wood. Combine 1 cup vinegar with 1 gallon water. Then, pour it in a bucket with a wide top. You can also use wood cleaner or professional deck cleaner.

Ermita Rubias


Will bleach kill algae on decking?

The affects of bleach on wood decks and fences
On wood, however, the chlorine kills algae, moss and mildew. As a cleaner, bleach provides minimal results.

Parminder Boleu


Can I use OxiClean to clean my deck?

OxiClean is safe to use on decks. When cleaning your outdoor deck, the oxygen bleach is a much better alternative than chlorine bleach as it cleans any deck surface without causing discoloration or damage to plants, shrubs, soil and similar surroundings.

Elizbeth Verdier


How do you remove green mold from wood?

Steps to Remove the Mildew and Mold:
  1. Begin by mixing three parts water with one part bleach in the bucket.
  2. Fill a second bucket with plain, clean water.
  3. Moisten a sponge with the solution and gently scrub the mold and mildew until it is gone.
  4. When all of the mold and mildew is gone, rinse completely with clean water.

Modestas Manota


What kills algae on decking?

Clean your wooden deck at least once a year to help prevent moss and algae growth.
  1. Fill a bucket with 1 gallon of warm water and add 3/4 cup of chlorine bleach.
  2. Pour the bleach solution onto the wooden deck.
  3. Scrub the deck thoroughly with a scrub brush to remove all of the moss and algae.