Is Composite Decking Good For Docks?

When choosing the right material to build your dock, there are quite a lot of options to choose from. With newly developed technology, the choice now ranges from wood or metal to composite, capped composite, PVC, and more! While they all have pros and cons, here we are going to discuss composite decking, and whether or not composite decking is good for docks.

The best composite decking for docksOpens in a new tab. is durable has limited absorption of water and is resistance to the harmful effects of the sun’s UV making it ideal decking for docks.

Docks are impacted by two of the most damaging elements, the sun and water. Making the selection of the right decking is the difference between enjoying your dock for years to come and replacing it.

If you are not quite sure of the differences between composite and capped composite decking, you have come to the right place! We are going to discuss every similarity and difference of these two options, including the benefits and possible deficits of using one or the other as your decking!

Composite Decking for Docks?

Composite decking has been on the market since 1990, but it has come a long way since then. It has become an extremely popular choice for docks for many reasons, but it’s important to note that it also comes with quite a few flaws. 

Pros of Composite Decking for Docks

We have done extensive research that shows that composite decking is good for docks, and here’s what we found: 

  • This material is durable. Composite can last between 25 and 30 years before it needs to be replaced (usually with warranties that last just as long.)Opens in a new tab.
  • Composite decking is environmentally friendlyOpens in a new tab.. It is made from recycled plastic and wood fibers or saw dust from timber mills, which are then blended together and formed into decking boards that imitate wood planks. 
  • It requires far less maintenance than wood decking. The moisture from the inevitable waves and condensation of evaporation water can wear down the bottom of a dock in no time. This requires repainting, repairing rotten slabs, and even building entirely new docks long before a composite dock will have any problems at all.

As technology has progressed over the past 30 years, so have composite docks. While the material has become much more efficient and reliable over time, there are still issues that can arise.

Cons of Composite Decking for Docks

If you have ever walked on a composite dock you may have already noticed some of these issues, and some others are important but fairly hard to detect.

  • Composite decking is made partially out of plastic, as we know, which can cause a dock made of the material to become exceptionally hot. If you choose composite decking, make sure to wear some kind of covering for your feet when walking on it. 
  • The material itself is fairly heavy. This can cause problems when attempting to build floating docks, and it requires an intelligent architect to design the dock so that it is stable enough to sustain the wait the composite.
  • Composite is slippery. Once again, as you will inevitably be traveling to and from the water on your dock, it is important that you stay safe! Watch your footing and take it slow if you choose to use composite to build your dock.

Now, these may or may not be decision-making shortcomings for you. It truly depends on what your dock is being used for, who is using it, and how big it is going to be. But before you make your choice, let’s discuss what capped composite decking has to offer. 

Capped Composite Decking for Decks?

Capped composite decking is simply the newest face of composite decking, and it’s great for docks! In fact, some experts say it is the best material you could possibly use to build your dock.

The addition removing many of the problems of composite decking while increasing appearance.

Pros of Capped Composite Decking for Docks

  • Capped composite decking is made in the same way that composite has always been made, so it is also durable, long-lasting, and made from recycled materials. However, there is an important new feature: capping.
  • Capping is made from a polypropylene or polyethylene plastic blend covering and protecting the composite just like a shell of a golf ball covers the center.
  • The amount of capping varies by brands. Fully wrapped decking is better suited for decks with high water exposure on the bottom of the deck. FiberonOpens in a new tab. and TimberTech’s higher end lines are capped on all four sides. TimberTechOpens in a new tab. goes as far as complete cap including inside the groove.
  • The capping is bonded to the composite during production, to ensure no moisture will affect the boards on either side.
  • The composite capping can also improve traction, either by woodgrain embossing or rougher textures. DeckoratorsOpens in a new tab. (MBC) decking has one of the highest rated composites for traction.
  • Capped composite decking is UV resistant, ensuring that your dock can withstand the weather and will never fade or need to be painted.
  • Composite decking also does deteriorate developing annoying splinters on the dock boards
  • Composite decking have low levels of water absorptionOpens in a new tab.. Minimizing the impacts of waves splashing on the dock. Again DeckoratorsOpens in a new tab. (MBC) is amazing, absorbing less than <0.05% after soaking for 24 hours. But Fortress deckingOpens in a new tab. is not far behind. I fact almost all composite decking performs well around water.
  • Lasting 25 to 50 years, along with equally long warranties.

Cons of Capped Composite Decking for Docks

While there are very few negatives to choosing capped composite decking for your dock, there are a couple to note. 

  • Capped composite decking is more expensiveOpens in a new tab. than wood. But the good news is, with newer scalloped boards the price has decreased but so has the amount of capping. Most economical boards are only capped on three sides.
  • Compared to wood, composite decking is a heavy materialOpens in a new tab.. On average 45% but this amount varies by brand and profile. A dock built with composite decking will need to be designed for the additional weight.

How Does Composite Decking Compare to Other Materials

As we mentioned, there are quite a few other materials that you could use to build your dock. Even though we think that capped composite decking is the best choice, we wanted to break down a few of the other options and what they offer. 


While PVC decking actually has a lot in common with composite decking, for example, their similar durability and environmentally conscientious material make-up, there are a few important distinctions.

  • PVC will develop less mould with no organic material for mould to feed on.
  • PVC is typically more expensive.
  • Composite decking provides a more classic aesthetic as it can look like wood and not plastic. 
  • PVC decking offers better traction when wetOpens in a new tab..
  • PVC is generally cooler in the sun than composite

These are a few ways that PVC decking is better for docksOpens in a new tab. than composite.


Most users are really shying away from using wood to build new docks, and for good reason. Wood, while a cheaper option, warps easily with moisture, weathers in the sun, needs constant maintenance and repainting and truly does not last nearly as long. 

Especially now that composite can have a wood-like look, there are very few pros to choosing wood for your dock. 


Aluminum decking is actually a pretty great option for docks as well. In regards to longevity, aluminum may take top prize as it could possibly outlive you! 

When choosing aluminum, you will have to resign to the fact that it may not go with the rest of your decor, unlike composite decking, which looks similar to natural wood and comes in a variety of colours, aluminum pretty much just comes in metal colouring. 

The only way that composite is better than aluminum decking for docks is its appearance. The Composite is designed to look good. Even out on your dock.

As you can see, almost every alternative has several pros and cons, so it is really up to you when it comes to choosing which material is perfect for your dock.  

Final Thoughts on Composite Decking on a Dock

We the question, is composite decking good for docks?

And hopefully, you now know that YES composite decking is great for docks, albeit with a few cons that you may want to consider and be cautious of whenever you build and use your new composite dock. Capped composite is the best for docks.

There are many composite decking brands. Click the link to see some of the best composite decking brands Opens in a new tab.on the market.

Check out Dr.Decks build a composite deck.

Ryan Nickel

A Red Seal carpenter, passionate about building decks to be enjoyed.

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