One of the best decking materials is composite decking, as it is ultra durable and low maintenance while preserving the natural charm of wood. However, have you ever thought about what’s the best deck joist material? Is composite wood joist the optimal choice for your composite decking? Don’t worry. In this article, we will discuss the 4 main deck joist materials and help you find the best one.
To ensure your deck’s durability and safety, you must consider not just robust decking materials but also its substructure. With various deck joist materials available, selecting the right type of joist can be challenging. To aid your decision-making, let’s delve into the four popular deck joist options.
What Are Deck Joists and Their Significance?
Deck joists serve as the foundational support structure beneath the decking surface, crucial for bearing the weight of the deck and its occupants. Not only do they offer stability and durability, but deck joists also play a vital role in ensuring adequate water drainage. By creating a framework beneath the decking boards, these joists elevate the deck slightly off the ground, preventing moisture accumulation and reducing the risk of rot or mold formation. They are essential for constructing a secure, long-lasting deck that not only looks great but also functions effectively.
Pros and Cons of 4 Major Deck Joist Materials
When choosing deck joist materials, four primary options stand out: wood, composite wood, aluminum, and steel. Each material offers unique benefits and considerations. Below, we examine each in greater depth.
Timber
Pros: Affordable, easy to install, low expansion and contraction
Cons: Vulnerable to rotting/insect damage, shorter service life, combustible
Wood joists have long been the traditional choice for decking subframes. However, their weaknesses have become increasingly apparent, leading to the popularity of alternative materials. Wood degrades more rapidly than composite or aluminum joists, resulting in a shorter expected lifespan. Water damage can cause wood joists to sag and warp, affecting the integrity and safety of the decking surface. Additionally, wood is combustible and may not meet fire safety regulations in some areas.
Composite
Pros: Durable, resistant to rotting/insect damage, noncombustible, eco-friendly
Cons: Heavy, susceptible to expansion and contraction
Composite decking is a new eco-friendly material in recent decades, and so is the composite joist. They are crafted from a blend of wood, plastic, and bonding agents. Composite joists come in solid and hollow profiles, and the solid type is recommended for decking projects.
These composite joists address the shortcomings of solid wood joists. They are resistant to rotting, mold, and insect infestation, and offer a longer service life. However, due to the inclusion of plastic, they are prone to expansion and contraction, which may result in warping, splits, and uneven surfaces after significant temperature changes. Moreover, the quality of composite joists is also crucial. High-quality composite joists enjoy a reasonable lifespan, while poor-quality ones may not be better than wood.
Aluminium
Pros: Ultra durable, lightweight, no expansion and contraction, noncombustible, maintenance-free, corrosion-resistant
Cons: Higher initial cost
Aluminium joists are the best choice for construction professionals seeking uncompromising strength, longevity, reliability, and performance, while also preferring a lightweight and versatile material. These joists offer a remarkable lifespan and durability, significantly reducing maintenance requirements and the need for replacements over time.
Feelingwood’s aluminium decking joist is purpose-built for swift and simple installation, accommodating diverse configurations and applications. It is non-combustible, satisfying government fire regulations for external terraces and balconies on residential buildings. Unlike composite wood joists, aluminium exhibits minimal expansion or contraction, ensuring consistent performance and structural integrity.
Steel
Pros: Durable, low expansion and contraction, noncombustible, invulnerable to rotting, warping, splitting and pesky insect damage
Cons: May not so corrosion-resistance
Steel joist is also a metal joist option which comes with the benefits of durable, low no expansion and contraction, noncombustible, maintenance-free. However, it’s worth noting that steel joists may not be as corrosion-resistant as some other materials. Long-term outdoor exposure to moisture and humidity can lead to rusting and degradation over time. This may require additional maintenance or coatings to protect the joists from corrosion.
Additionally, compared to aluminium joists, steel joists tend to be heavier. This increased weight can affect ease of installation and transportation, requiring more labor and equipment to handle and install steel joists effectively.
In conclusion, aluminium decking substructure joists offer unparalleled support for decking boards, combining ease of installation with exceptional strength. Their continuous fixing channel seamlessly guides screws in place, providing superior pull-out strength. This robust yet versatile substructure surpasses the performance of composite or timber decking joists, ensuring optimal stability and longevity for any decking project.
Feelingwood Fast-Installation System – The Fastest Composite Decking Installation Solution
To learn more about our composite decking and aluminium joists, head to our Fast-installation system page or get in touch with the Feelingwood team to discuss your needs and how we can help you with your next decking project.
