Categories: Hardwood Decking

How To Remove Mold Off Decking

If you’re the proud owner of decking and are frustrated at the build up of green algae that seems to keep spoiling its look, help is at hand.  In this article, we want to propose a few ways to help you remove mold off your decking.  The first thing to say about mold or green algae is that it’s a very common problem on decking and isn’t something to be overly worried about.  The bad news is that there appears to be no way of stopping it happening.  All of that said, there’s no getting away from the fact that mold and algae does spoil the look of your decking at the same time as making it slippery to walk on, so action must be taken to remove it!

No matter which method of cleaning you choose, you need to make sure your deck is clear of all furnishing and pots as well as surface dirt and debris.  The best way to do this is to clear your decking entirely of furnishings and pots and sweep the deck thoroughly with a stiff brush, making sure you get right into the corners where mold and algae have a tendency to build up.

Thereafter, the first option is to buy an algae removing product from your decking supplier, which has been designed and developed with the sole purpose of removing mold from your decking.  Available in “green” or “eco” (and some not so green options), essentially what these cleaners do is attack the moss, algae and lichens that cause your decking to look a bit tired.

Many varieties of algae remover come in a concentrated format that you need to dilute, but if you’re unsure of this type of option, it’s best to choose a pre-mixed solution.  Most decking suppliers will be able to recommend an algae removing product that is suited to your particular decking, so do take the opportunity to seek advice if you’re in any doubt.  The way these products normally work is that you apply them to a clean surface and leave them to react with the algae or mold for a specified amount of time.  Thereafter, it’s a case of rinsing the deck, or in some cases, brushing the product away with a stiff brush.

If you prefer a more homemade approach, then you’ll need to arm yourself with a garden hose or power washer (set on a gentle setting), a bucket, a sponge and an oxygen-based bleach and water solution.  If you are worried about the effects of using bleach on your decking, check with either your decking supplier or any reputed supplier beforehand that a bleach-based solution won’t harm your finish.

What you need to do is cover the entire deck area with the bleach solution and leave it for about 15 minutes.  During this time, the solution will start to break up the mold and algae that’s visible and will also be working away to kill off at any traces that have yet to appear.  Once the bleach solution has had the chance to take effect, either power wash the solution away (on a gentle power setting) or simply hose it away.  If you find you have stubborn patches that remain, you can repeat the process and, if necessary, scrub the remaining areas with a stiff brush, all the time being careful not to damage the surface of your deck.

TOP TIP: Be careful, no matter which type of product you use, to thoroughly hose the surrounding area (if planted) with clean water to help protect your plants from any negative effects of the chemicals.

If you find that neither of these approaches does the trick, then the worst-case scenario is that you’ll need to have your deck sanded and re-finished.

FAQ

What causes the build-up of green algae on decking?

Green algae build-up on decking is a common issue and tends to happen due to natural environmental factors. It can spoil the look of your decking and make it slippery to walk on, which is why it’s recommended to remove it.

How can I prepare my deck for cleaning?

Before you start the cleaning process, clear your decking entirely of furnishings and pots. Next, sweep the deck thoroughly with a stiff brush, ensuring you clean the corners where mold and algae tend to accumulate.

What types of products can help remove algae from my deck?

You can purchase an algae-removing product from your decking supplier, which is specifically designed to remove mold from your decking. These products come in both “green” or eco-friendly options and other varieties. They work by attacking the moss, algae, and lichens that cause your decking to appear tired.

Can I use homemade solutions to clean my deck?

Yes, a homemade approach involves using a garden hose or power washer (set on a gentle setting), a bucket, a sponge, and a solution of oxygen-based bleach and water. After applying the solution, allow it to work for about 15 minutes before rinsing it off.

What if neither commercial nor homemade solutions work?

If neither commercial nor homemade solutions work to remove the algae, you might need to consider having your deck sanded and re-finished. This is a more drastic measure and should effectively remove any stubborn algae or mold.

Jonathan Sapir

Jonathan Sapir has over 17 years in the flooring industry. As an authority on flooring, he infuses his extensive knowledge and passion for quality products into every article. Jonathan's expertise helps readers make informed decisions for elegant and durable flooring solutions.