In our first article in this series, we started our exploration of the differences in quality between wood or composite decking for use in boardwalks. As we mentioned in the first article, wood is more user-friendly than composite decking, because it is less likely to cause burns to bare feet and also less likely to pose a slip-and-fall hazard. In this article, we’ll take a look at the difference between the durability of wood decking and that of composite decking.
Wood Decking is More Durable Than Composite Decking
There are several different ways you can measure a product’s durability. For example, how resistant is it to mold, insects, and the weather? How hard is it? How well does it withstand potential scratches? How strong is it? We’ll look at each of these questions and discover which decking material, wood or composite, is the most durable of the two.
Wood Decking is More Mold, Insect, and Weather Resistant than Composite Decking
People often assume that, because composite decking is made of mostly plastic-based materials, it will naturally be more weather and mold resistant than wood. After all, wood is an organic product, so it should be more susceptible to mold and weather, right? Actually, that assumption is completely false. In order to make this point clearer, let’s take a look at the history of composite decking materials.
When they first came out, composite decking materials were composed of wood flour and polyethylene. In spite of the plastic binders that held the two materials together, these early composites tended to break down quickly due to the absorption of moisture into the wood flour. They were quickly taken off the market after multiple class-action lawsuits were filed. Afterward, they were replaced with newer, more durable composites. But these still had plenty of problems.
The new composite materials were designed with a cap stock plastic casing on them. This was supposed to keep the composite decking safe from the elements. The problem is that the plastic case tends to crack in the heat or gets separated from the inner core. Mold and decay can set in once the outer shell is compromised by any kind of scratch or puncture. As soon as the inner core is exposed, it is susceptible to these kinds of adverse reactions. Each time a composite deck is installed, the exterior has to be punctured by screws or cut to even out the length.
In contrast, consider the natural mold, weather, and insect resistance available from natural hardwoods. Those typically used for decking materials, such as Cumaru and Ipe, have a high degree of protection due to their ability to correctly take in and release moisture. They produce resins that fight off mold and deter insects. When wood is ground into pulp to make composite decking, it loses these helpful elements. Mold grows readily on ground wood flour.
In our next article, we’ll continue to explore the topic of whether wood or composite decking is the most durable material to use for constructing boardwalks.