Composite Decking is the leading building product used to build decks in America and in many parts of the world. Many composite deck brands also give the appearance of real wood instead of nasty plastic. The appeal of using recycled materials to create an outdoor deck has many builders and homeowners excited and eager to start building right away. However, because composite decking is not real wood, it behaves differently throughout the course of the year.
Heres the first thing you need to know: While hardwood decking expands and contracts on its width due to environmental changes in temperature and moisture levels, composite decking will expand and contract on its length. This is an important distinction to make. Lets just say that if the ends of your composite deck boards butt against your home, you may want to give some breathing room while installing. Not much, of course, but enough to allow the boards to expand and to prevent buckling, warping, and cracking.
Now comes the fun part, installing composite decking. Many builders say that screwing directly through the top of the board is just fine. I couldnt disagree more. Just because composite boards are made of recycled content doesnt mean that theyre cheap. Screwing top down will mean that your finished deck will look decent from far away. And, the closer you get, the more dots aka screw heads youll see. Now the naysayers out there will say that there are composite deck screws that have colored heads that match the decking. Sure enough, theyd be right. However, what those special decking screws or any other brand for that matter cant do is prevent the problems of mushrooming, mold, and decay that this method of deck installation ends up with? Why? Because that method is the one of the causes of those problems!
Lets explore this further. Lets say you rush through your decking installation. Top down screws everywhere! Now, fast forward a few months, a year, maybe two. Theres been a lot of rain, maybe some snow, ice, and a lot of time for water to sit and rest around the heads of each screw. Gravity being what it isat least SOME water will seep into the crevices that arise. Where did these crevices come from? Think about it. Those screws are driven through the deck board into the joist so that your deck board wont move. But, if you remember from above, all types of decking will move. So, with this in mind, the decking moves on its length and the screw…does it stay in place? No, it will move around too. These movements can be incremental, or they can be noticeable right away depending on how well the decking was manufactured and/or the climate you are in. Regardless, the result of water seeping into the screw hole will lead to mold and eventually decay. Two things that will make any deck look horrible and an eyesore.
So, how do you prevent this from occurring? Use hidden deck fasteners tailor made for composite decking. A composite deck fastener will be installed between each board straight down into the joist. You might have to use a biscuit jointer or router to fashion the grooves yourself, or if you bought pre-grooved composite deck boards, all youll have to is lay the board down, straighten it according to your plan, and then install the composite fastener using a screw and drill. Thats it. Simple as pie, not to mention an effective way to make your outdoor garden deck look as good as new for a longer period of time.