What’s The Difference Between Traditional & Capped Composite?

If you’ve been searching for the ideal composite decking for your garden, you’ve probably come across capped and uncapped composite decking. Whilst both are good choices for most decking projects, there are some differences that you’ll need to consider when choosing between the two.

In this article, we’re going to take a look at the main differences between the two types of composite decking. We’ll also focus on the benefits of capped composite boards and why we think they’re the best option.


What Is Uncapped Composite Decking?

Uncapped composite decking boards are the traditional form of composite decking. They’re made from a mixture of recycled wood fibres and plastic polymers. The same material all the way through the product.

During manufacturing, the material is melted down through a process known as extrusion. The molten material is then passed through a die which shapes the material into uncapped composite decking boards.

Although they’re still high-quality composite decking boards, they’re left uncapped which means the wood fibres are left exposed. Some people prefer the appearance of uncapped boards because the exposed wood gives them a similar look to traditional wooden decking.

Even without being capped, these boards are still very water-resistant, durable, and have great longevity. The rough texture of uncapped decking also makes it very slip-resistant, and it can be an ideal choice for installation around swimming pools.


What Is Capped Composite Decking?

Capped composite decking has the same core as uncapped decking but also has a polymer sleeve around it that provides extra protection. This polymer sleeve covers all sides and edges of capped composite boards to prevent water from penetrating into the core of the boards.

This added layer of protection has several benefits and means that capped composite decking is the more durable of the two types of composite decking.

Capped composite decking is now the most popular type of composite decking due to its many benefits. This means that most of the composite decking now on the market is capped decking. There are numerous types of co-extrusion (capped) composite decking. We believe that our Forma and Grande range have the best brushing techniques on the market, making the deck board look realistic, just like timber.


Is Capped Composite Decking Better Than Uncapped Composite Decking?

Capped composite decking offers many of the same benefits as uncapped composite decking, but it does have a few advantages.

When building a composite deck, some of your main considerations will be the durability and longevity of the composite decking you choose, as well as its overall appearance.

So, let’s take a close look at why capped composite decking is probably the best choice for your decking project.



Uncapped decking is very aesthetically pleasing, and its exposed wood fibres can give it the appearance of traditional wood decking. For some people, this look is preferential, but the styles and colours of uncapped decking are slightly limited.

Capped composite decking has more versatility when it comes to appearance, and the range of colours and styles available tend to be more extensive.

This gives you more choice when designing your composite deck, and it should be easier for you to find a style and colour scheme to suit your home and garden.

Capped decking also has a more sleek and refined appearance than uncapped decking due to the smooth finish of the polymer sleeve.

Ultimately, which type you prefer in terms of appearance will come down to personal preference. Both uncapped and capped composite decking are visually appealing but for different reasons.



When it comes to maintenance, there isn’t a significant difference between uncapped and capped composite decking. Both are made from the same materials which mean they don’t need to be treated, sealed, or stained during their lifespan.

Both types of composite decking are very low-maintenance and only need to be occasionally cleaned. This can be done using a power washer or warm, soapy water and a soft bristle brush. Usually, both uncapped and capped boards will only need to be cleaned around once every 6 months.

The only difference between the two is that uncapped composite decking is slightly more porous than capped composite decking. This means that over time a small amount of moisture can be absorbed into uncapped decking boards.

It’s possible that this could lead to the formation of a small amount of mould or algae. If this is the case, these boards will need to be cleaned more often than capped boards would.

However, this is fairly unlikely and if mould or algae did form on uncapped boards, it would still not compromise the durability of the boards.



Both uncapped and capped composite deck boards are made from recycled wood and plastic, which means that they’re resistant to rot. In this respect, both have an advantage over real wood, which absorbs water and rots if not properly treated.

As they’re rot-resistant, capped and uncapped boards both have amazing longevity. On average, you can expect composite decking to last between 25 and 30 years.

However, as capped composite decking has an added layer of protection, it is more resistant to the elements and often will last even longer than uncapped boards.

The capped boards in our Clarity range all come with a 20-year guarantee, and the boards in our Forma range all have a 25-year guarantee.


Stain resistance

All composite decking is resistant to staining, but capped decking is more stain-resistant than uncapped decking. The extra layer of polymer coating on capped composite decking means that spilt liquids remain on the surface of the boards and can be easily wiped away.

This greatly reduces the chance of any staining from occurring, and in many cases, the spilt fluids will simply run off the surface of the boards themselves.

This is particularly beneficial if you’re planning to install composite decking around a swimming pool as fluids such as sun cream are more likely to be spilt onto the boards.

Uncapped boards are at a slightly higher risk of staining as they don’t have the extra protection of a polymer sleeve. This means that the exposed wood of the boards is more absorbent and spilt fluids could cause stains if left for too long.

However, as long as fluids are cleaned off uncapped boards fairly quickly, this shouldn’t be much of an issue. When compared to other materials such as wood decking, uncapped boards are still far more stain-resistant.



It probably won’t come as much of a surprise that capped composite decking tends to be more expensive than uncapped composite decking. On average, it costs around £40 per square metre for uncapped boards and around £80 per square metre for capped ones.

The higher price of capped composite decking is usually worth paying due to the reasons that we’ve highlighted above. For example, the increase in longevity that capped composite decking provides means it’s highly unlikely you’ll need to repair or replace it during its service life.

There is also another often overlooked factor that may make the higher price of capped composite decking worth paying. If you’re planning on selling your property, then capped composite decking will most likely be a more appealing feature than uncapped decking.

This is due to the fact that most people consider capped composite decking to be of a higher quality than uncapped decking, and this could increase the value that potential buyers place on your property.



One area in which uncapped composite decking has an advantage over capped composite decking is the availability of the products. As capped decking is more costly to produce, the rise in its popularity has led to it being more difficult to source than uncapped decking.

This of course depends on the supplier that you use but usually, capped composite decking will have a longer lead time than uncapped. This shouldn’t be too much of an issue for most people.

However, if you need to start construction on your deck within a short window of time, then it’s possible that using capped composite decking could slow the process down.

Due to the other advantages that capped boards have over uncapped boards, it may still be worth waiting the extra amount of time that it could take to receive them.



Can capped composite decking be painted?

You can paint capped composite decking if you’d like to. If you do decide to, it’s best to use a primer first and then a coat of acrylic paint. However, we wouldn’t recommend painting our composite decking as it’s unnecessary and won’t increase the durability or longevity of the boards.

It also means that your composite decking will then require more maintenance as you’ll need to repaint it fairly often. This will detract from one of the main benefits of having composite decking in the first place, which is its lack of maintenance requirements.


Does capped composite decking get hot in the sun?

Like most decking materials, capped composite decking will get hot when exposed to the sun for long periods of time. This means that it will feel hot underfoot.

As composite decking is designed to withstand thermal expansion, this shouldn’t lead to warping and won’t decrease the longevity of the boards. However, if you want to reduce the amount of heat that your boards absorb, than opt for lighter colours rather than dark ones.


Do I need to use a composite deck cleaner on capped composite decking?

You don’t need to use a composite deck cleaner on capped boards. The best ways to clean them are to use either a power washer or warm, soapy water. If you need to remove any stains from capped composite decking, then you can use a mixture of vinegar, baking soda and water.

It is very rare for capped composite decking to stain though, so it’s unlikely you’ll have to do this.


Final Thoughts

Although both capped and uncapped composite decking have fairly similar attributes, capped composite decking is the better option overall. Its extra layer of polymer coating gives it slightly better durability and longevity than uncapped composite decking and the extra cost is usually worth it.

If you’ve decided that composite decking is for you, check out our range of products today. You won’t be disappointed.

Gary is the founder and CEO of Ecoscape UK. Gary graduated from Liverpool JM University in 2007 with a 2:1 in Economics. A passion for innovation, design and sustainability, Gary has put to market numerous wpc products/systems, some of which have UK and European registered designs. Outside of work Gary enjoys spending time with his family, the great outdoors and watching Manchester United.