Aluminium vs Plastic Decking

Decking is a fantastic way to improve any garden or flat roofing area. In recent years, there has been a spike in homeowners looking for a longer lasting alternative to timber decking as it has well known quality challenges.

With many different decking board materials now available on the market it can be difficult to know which the best is to choose. In this blog, we will look at aluminium decking versus plastic decking to determine which one is better and demonstrate why you should switch.

5 Reasons to Switch to Aluminium Decking

  • Lifespan & Durability
  • Cost
  • Sustainability
  • Fire Rating
  • Appearance & Colour

If you’re looking for a quick answer you can skip down to our summary by clicking here.

Lifespan & Durability

The lifespan of your decking is one of the most important factors when considering what deck material will be best. It can be quite costly if you invest all the money only to have to replace it again in 5 years. Limited lifespan is a major flaw of timber decking.

By comparison, the estimated lifespan of robust aluminium decking can be up to 60 years.

So how does aluminium decking have the best lifespan? Well, that's simple, aluminium decking will simply not crack or mould and over time it will maintain its strength properties.

Once you install your aluminium decking it would be very rare to have to replace it in decades.

Aluminium decking is not only durable in the winter months but also in summer, which removes the worry about warping and discolouration compared to plastic decking.

Plastic decking has a substantially shorter life span. The reason for this is fading and discolouration over time, which especially can be an issue in areas that are commonly exposed to the sun.

Longest Lasting Decking = Aluminium Decking


There is no doubt that aluminium decking is going to be more expensive than plastic upfront. However, when you are investing in decking you want to ensure the material has strong longevity, so it is important to weigh up the long-term financial benefits of paying more upfront and gaining better long term ROI.

Aluminium decking is a very good value for money simply due to its outstanding lifespan and endurance. For example, the market-leading Alupave decking has an estimated 20+ year lifespan with many decks lasting up to 60 years.

Although plastic decking does tend to be cheaper you have to bear in mind that you get what you pay for. Any plastic items outside tend to be subject to deterioration from weather conditions and the sun. This is going to cause your decking to look awful in a matter of years. Eventually, fading will cause it to become brittle and crack causing you to replace your decking again.

The best solution for this is to install the right decking material the first time, Aluminium Decking!

Aluminium Decking boards have been designed to ensure they have extraordinary spanning properties. This amazing feature is a huge benefit as it allows you to save time and money with a smaller substructure.
Aluminium Decking is one of the easiest materials to use simply down to there are no fiddly clips or brackets.

Another big cost saver is that modern aluminium decking systems have a fantastic feature of an inbuilt drainage between each board which prevents any rainwater from hitting the substructure beneath. All surface water can be channelled down the board drains and around the patented decking gutter system.

How does this save money? It allows you to use a low-cost timber frame as there is a substantially reduced risk of the decking joists getting damp or rotting. In fact, the deck will be fully sealed and fully waterproof.

So, the surprising answer is that installing aluminium rather than plastic decking boards will likely save you £1000s in just the first two years after installation.

Cheapest Decking = Timber
Most Economical Decking = Aluminium Decking


More than ever, we are focussing on ensuring a greener planet. Looking at ways we can make environmentally friendly changes and decisions to make the planet a better place to live. Aluminium decking is the greenest choice for decking materials. It is a natural element that is an environmentally friendly option.

Aluminium is 100% recyclable and loses none of its original qualities in recycling, which is fantastic for the environment.

Conversely, a plastic decking board is not particularly a green choice. Plastic is oil based and during the manufacturing process, harmful chemicals are released which then escape into the environment and can cause bad pollution issues or lead to environmental damage.

Plastic decking will need to be replaced more frequently and these replacements will more than likely end up in a landfill as it takes many years to decompose. Landfill has a significant impact on our environment in today's world when we are trying hard to change and become a greener generation.

Most Sustainable Decking = Aluminium Decking

Fire Rating

The biggest advantage of using aluminium decking is the fact it is non combustible, which gives the advantage of being able to install it on high-rise balconies. For obvious reasons, plastic deck boards are simply not an option!

However, even on a ground-level decking safety should come first as there are many fires started from the patio heaters, BBQs, and fire pits. Simply installing aluminium decking reduces any fire risk.

It is worth noting that most aluminium decking has an A2 Fire Rated meaning it's the ultimate choice between the two materials, especially where non-combustibility is a key requirement. Alupave is the best aluminium balcony decking solution currently available.

Aluminium has natural fire-safe qualities which gives an excellent advantage as it can be used on high-rise buildings as a safe, non-combustible option. This is why it is a popular metal for other non combustible building products such as aluminium gutter systems.

The only other non-combustible options are fibre cement decking boards which are very heavy so are too much weight for a balcony or terrace situation.

If you choose to install plastic decking you need to be aware of another safety issue; plastic is prone to becoming very slippery, especially in poorer weather such as snow or rain. It makes it very hard to walk on without falling and if you have elderly or younger children at home it can quickly turn into a dangerous situation.

Choosing to install aluminium decking gives you peace of mind as it has had a few anti-slip tests proving its effectiveness.

Best Non Combustible Decking = Aluminium Decking

Appearance & Colour

The good news is both types of decking have a wide variety of colours available which is great for your garden aesthetics. However, quite quickly decking plastic boards can start to fade.

Discolouration is a very common problem with cheap decking. The main cause of plastic decking fading over time is due to the sunlight (UV Rays) degrading the surface of the board. Nonetheless, there are still other factors that can contribute to a fading decking such as:

  • Poor Maintenance
  • Certain Cleaning Products
  • Exposure to Moisture

It is worth pointing out that once your decking begins to fade there is very little you can do to bring it back to life.

Aluminium on the other hand has some fantastic benefits as aesthetically it looks fantastic with a modern style and as we have just discussed it won't look dull or fade fast over time. Another factor worth mentioning is aluminium does have a seamless look, which is mainly down to hidden connectors and external corners. Meaning your decking will look stunning in your garden.

Did you know? Alongside the most popular colour dark grey you can buy aluminium decking in any RAL colour to suit your project.

The last thing you want when you are on your decking is to hear cracking and squeaking noises. This can happen with friction and pressure from the material which leads you to hear these noises.

If you want to avoid these unnecessary noises the way forward would be aluminium decking. It has been manufactured with optional gaskets to provide underfoot cushioning – a very unique patented feature which you won't get with any other decking material!

Best Looking Decking = Personal Preference

Should I install Aluminium rather than Plastic Decking?

Throughout this article, it has been clear that compared to plastic decking the ultimate decking material to use is aluminium decking.

Using aluminium decking simply allows you to install decking with complete confidence given its excellent advantages of sustainability, strength, and durability.

Although plastic decking is a low-cost option that may save money initially it isn’t a smart choice to install, given its low life span and strength.

One of the key benefits that prove aluminium is the way forward is the fire safety aspect. It makes aluminium decking the go-to choice for ground floor or high-rise balconies and roof terraces, as you would never be able to use plastic.

To summarise here is a list of the pros and cons of plastic decking and a comparison table below.

5 Disadvantages of plastic decking:

  • Discolouration and fading from the sun
  • Low strength – easily breaks
  • Doesn’t have inbuilt drainage like aluminium
  • Fire hazard
  • Warps and goes brittle


Material Pros Cons
Aluminium Decking Safety – Non-Combustible Higher initial cost
In-built Drainage Requires Metal Chop Saw to cut
Longest Lasting
Plastic Decking Cheap Initial Cost Fades and discolours
Tradditional Look Cracks and breaks easily
Attracts algae, mold and moss
Not Eco Friendly
Short lifespan
Very warm in the sun
Goes brittle in the sun



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