Disadvantages of composite decking

A deck is a great way to maximise your outdoor living space and increase accessibility. The question is – how do you choose the right decking product?

While traditional decking timber has been used in the past, deck alternatives are becoming increasingly popular. 

While innovative products like composite decking offer a range of advantages, it also pays to know the potential problems they can bring. In this blog, we will focus on explaining when composite wood decking is not a good option. 

What is composite decking?

Composite refers to a product that is made up of more than one ingredient or material. Composite decking usually consists of timber and thermoplastic, with a few chemical additives. Compared to conventional timber decking, composite offers the following benefits: 

• Lightweight and easy to install.
• Minimal maintenance is required. 
• Durability.
• UV resistance. 
• Can contain recycled plastics, reducing landfill waste. 

How to install composite decking

To install composite decking, you will need to follow the same process as with timber decking. However, you don’t need to sand, stain, or paint the planks. Composite decking can be drilled, cut, fastened, and routed with standard woodworking tools. 

For example, our Millboard decking installation follows these key steps:

1. Build a level substructure, using joists and risers. 
2. Using a spacer between boards, lay the composite planks.
3. Secure the boards with Durafix screws.
4. Install fascias and square edging. 

Find all the decking accessories you need in our range, including Durafix screws, joists, joist risers, self-levelling joints, joist cradles, spacer tools, and side-fixing guide kit. We also have a wide range of fascias and square edges to ensure your deck looks polished and cohesive. 

Download the Millboard decking installation guide for free >

Problems with composite decking 

Below, we have outlined the most common problems that may arise when using composite decking products. We also explain how to mitigate these issues and provide alternative decking solutions. 

1. Moisture invasion

Uncapped composites contain exposed wood ingredients and are susceptible to mould and mildew. To avoid this, you can opt for capped composites, which are sealed with a plastic coating. Alternatively, use our Millboard decking range which has no real wood content, preventing rotting, warping, and algal growth. 

2. Contains thermoplastics

Some composite planks contain thermoplastics, which are a type of polymer that can be softened and melted when heat is applied. While this makes them easier to shape, it can also lead to warping after your plastic decking has been laid. 

Fortunately, some decking products are made without thermoplastics, such as our Millboard range. These composite boards are designed to provide mechanical strength, chemical resistance, and durability without the use of thermoplastics.

3. Cost

Composites typically have a higher upfront cost than traditional timber decking. However, the long-term maintenance savings usually make it more cost-effective over time. 

For example, our Millboard decking costs more per metre to install but does not need staining, sanding, or painting at any point in its lifetime. This will save you significantly in time and money over the decades. 

Learn more about why composite decking is more expensive than timber >

4. A fake wood finish 

While composite is available in various colours and finishes, it does not offer the authenticity of real wood. For some homeowners, this will be a problem while for others, a wood imitation or painted finish will be sufficient. 

However, note that our Millboard decking is made of resin moulded with real wood samples, achieving an authentic wood grain texture. This way, you can have the longevity and minimal maintenance of composite decking and a natural wood aesthetic at the same time. 

5. Fading

Whether it is natural or manmade, the harsh New Zealand weather will cause composite decking to fade over time. UV rays, weathering, foot traffic, sun lotion, and other chemicals spilt on the deck will all contribute to this. 

However, the higher the quality of the material, the less likely the boards are to fade. For example, Millboard decking has been thoroughly tested for UV stability under EN ISO 4892-2:2006 and achieved a 2% light reflectance value (LRV). This means it reflects more light than it absorbs and has a shift over 5,000 hours, offering exceptional colour retention. 

Millboard thermoplastic-free decking

At Forte, we supply Millboard decking, which is a composite material containing no thermoplastics. Instead, it contains high-performance polyurethane, which we mould into real wood grain samples. This combination gives Millboards its unrivalled durability, appearance, and safety. 

Made with a hybrid of polyurethane, Millboard planks do not rot, warp, or deteriorate. The polymer resin core is reinforced with fibre for extra strength and stability, making this one of the most dependable products available. Additionally, each plank is finished with a Lastane® surface to provide exceptional slip resistance, even in wet conditions. 

Key benefits of Millboard decking

• Less than 5% fading over 25 years. 
• Splinter-free and fixings are hidden beneath the surface.
• Easy to clean.
• Authentic wood grains and tints.
• Slip-resistant
• Easy to install
• Low impact on global warming and ozone depletion. 
• UKAS-accredited to the ISO 14064-1 Verified Carbon Footprint Assurance Mark. 

Are you interested in a reliable, safe, and visually appealing deck? Browse our Millboard range to find a style that complements your outdoor living design. From Blond and Natural to Grey and Beige and Brown to Charcoal, you’re sure to find a design you love.