Composite decks require minimal maintenance. They’re built for long-lasting beauty and durability. But like any product that is exposed to the elements, mold and mildew can begin to grow on your composite deck boards.  This can be especially true if a box or planter is placed directly on the deck.


Prevention is key.


Keep your deck clean with proper care including seasonal washings using mild dish soap, hot water, and a soft-bristled brush.  Lift planters off the deck using metal plant stands.  Remove cardboard boxes from deck as soon as possible.


If mold does form on your Trex or TimberTech deck, you’ll just need to put in a little work to get it looking great again.


If mold develops, a solution of baking soda, vinegar, and water can take care of the problem.

1.  Mix two parts vinegar and one part water in a bucket.

2. Pour the solution on the mold.

3. Then sprinkle a little baking soda over the area.

4. Let it set for 20 minutes. This will help to break up the mold and make it easier to remove.

5. Scrub the area with a soft-bristled brush and rinse well with water.


You can also use a mild commercial deck wash. But be careful. Always read the labels and follow the manufacturer’s instructions. It is always recommended to spot-check an area first



Do NOT use harsh chemicals or bleach to clean your composite deck. Although bleach will kill mold and mildew, these chemicals will lighten your deck boards and leave permanent discolorations.



Pressure washing is also NOT recommended. Composite decking is softer than natural wood. Too much pressure or applying the pressure too close to the boards can damage your decking.


For more on how to keep your composite deck or siding clean and looking new, check out our other blog posts or give us a call. We’re always here to answer any questions you may have.

Looking to install a new composite deck?  Contact ALLIED CONSTRUCTION AND RESTORATION at 248-238-8132 for a no-obligation quote.

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Allied Construction and Restoration is located in Highland, MI and serves South East Michigan.