How to Clean a Composite Deck

Have you been enjoying your deck but now it needs a little cleaning? You want to use the right tools when cleaning your deck so you can enjoy it for years to come.
 
Composite decking is one of the most carefree options for constructing a deck. It is important to properly clean and care for your deck. Remember there are certain materials that can damage your deck. 

Cleaning Mold, the hidden dirt!

Mold is one of the largest problems with a composite decking.  Although the surface looks solid, composite decking is actually quite porous.  This leaves areas for mold to form when water sets in the groves for an extended period of time. 
 
The best method for cleaning mold is to use a non-toxic, sodium percarbonate(hydrogen peroxide) based cleaner. Apply with a brush to reach into the grooves.
 

Power Washing, not your best option!

Pressure washing is not usually recommended for composite decking.  Pressure washing too close or using too much pressure can damage your deck. Composite decking material is softer than wood and can be etched. Once the material has been “opened up”, this can lead to other issues including chipping, sun damage, and mold staining. 
 
In most cases, a garden hose should be sufficient for regular duty cleaning.  If you must pressure wash, just remember to keep it at the lowest pressure possible and no closer than 8″ from the surface.

Protecting The Deck After Cleaning

One of the most important and often excluded steps in regular deck maintenance is to protect your deck against moisture intrusion.  Water left pooling on the surface of your deck can create problems such as mold/mildew growth, deck rot, and warping. The good news is that mold can be prevented with the application of a moisture barrier.
 
Choosing the correct product is crucial. Beware of any “waterproofing” deck sealants or chemicals that “encapsulate” the deck. These products can trap moisture inside the deck.  You want a non-toxic solution specifically for the purpose of inhibiting mold growth on porous materials, without damaging the surface or the environment. 

Forgetting the Gaps

One of the biggest contributing factors to Mold is a simple step most people overlook– the gaps! Dirt and debris can build up over time collecting moisture providing the perfect breeding ground for mold and mildew. Depending on your climate, the gaps between your deck boards should be cleared out at least once a year. This will allow the air to pass between the boards helping to keep the underside nice and dry.
 
Prevention is the real secret,  you want to use cleaners that will help stop mold and build-up before it causes problems later.