Our aluminium decking joists (3.6m) are designed for superior strength and long-lasting performance, making them the ideal solution for your raised composite decking project. Made from high-quality T6 aluminium, these aluminium joists offer exceptional corrosion resistance while remaining lightweight for easy handling and installation. The black powder-coated finish provides extra protection and ensures a discreet appearance beneath your deck.
Before installation, ensure you lay a weed membrane over any soil, grass, or previous vegetation areas to prevent unwanted growth beneath your deck.
Measuring 75mm (H) x 40mm (W) x 3600mm (L), these aluminium joists require adjustable pedestal supports every 1.2 metres, reducing the number of supports needed, which saves both time and money. This efficient design makes our aluminium decking frame perfect for creating a stable and durable foundation for your decking boards, whether you’re a professional contractor or a DIY enthusiast.
Securing the aluminium joists into position is straightforward, especially when using our decking clips supplied with self-drilling screws, ensuring a secure and stable decking structure. Perfect for creating raised deck areas, our aluminium joists offer the strength and durability you need for a deck that’s built to last.
Aluminium Joist FAQs
Are aluminium decking joists easy to install?
Yes, aluminium joists are lightweight and easy to handle. They can be quickly secured into place using self-drilling screws, and the spacing of pedestal supports at 1.2m further simplifies the process.
How do aluminium joists compare to timber joists?
Aluminium joists are more durable and weather-resistant than timber. They won’t warp, rot, or crack over time, making them a more reliable choice for decking substructures in outdoor environments.
Alternatively for non raised decks, our composite joist may be a more affordable option.
Can aluminium joists be used for both residential and commercial decking projects?
Yes, aluminium decking joists are suitable for both residential and commercial projects. Their strength, corrosion resistance, and ease of installation make them a versatile option for any decking application.








Excellent quality . Very well made . Light but very strong .
I would definitely recommend these to friends and family .
Absolutely brilliant
Very happy – very easy to work with to produce a high quality finish for steps and seating that should last for years.
Excellent products. We employed a joiner to create an extension to our glass canopy, using the materials bought from you. We are more than happy with the work and the materials used.
Good, easy to install. I have yet to compare with timber alternative but suspect cost difference is not that great after factoring in tape to go onto the top of the joists. As in my case, there was not enough depth available for timber because of restrictions around door cills and ground levels. Lower profile joists saved a lot of time and effort.