Decking Screws: Which is Best to Use for Your Timber Deck?

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Galvanized Decking Screw

When it comes to building a timber deck, the choice of decking screws might not be the first thing on your mind. However, it’s a decision that can greatly impact the longevity and performance of your deck.

Decking screws are the unsung heroes that hold your deck together, ensuring its structural integrity and aesthetic appeal. Typically, decking screws are used on the tops of deck boards, with normal nails and screws used for the frames.

Today, we will discuss the different decking screws as many people are unaware of the difference or that a special screw is needed for the top of the deck.

Understanding Decking Screws

Decking screws are specially designed fasteners used in the construction of timber decks. Unlike traditional nails, these screws provide a secure and long-lasting hold, reducing the risk of boards coming loose over time.

2 Main Types of decking screws used for decks

Steel Decking screws

Stainless Steel Screws

Stainless steel screws are renowned for their exceptional corrosion resistance. They are an ideal choice for decks in humid or coastal environments, where exposure to moisture is high.

Galvanized Decking Screws

Galvanized Screws

Galvanized steel screws are coated with a layer of zinc, making them resistant to rust and corrosion. They are a cost-effective option for many decking projects.

Size and Length Considerations

Choosing the correct screw size and length is essential for ensuring the durability of your deck. The appropriate screw length depends on the thickness of the decking boards you’re using. We offer decking boards in two thickness options: 22mm and 32mm. For 22mm thick decking boards, it is recommended to use 4.5mm x 60mm screws, while for 32mm thick decking boards, 5mm x 75mm screws are the suitable choice.

Screw Thread Types

Partial Screw Thread

Partial Thread

These screws have a combination of threaded and unthreaded sections along their shafts.

The threaded portion of the screw, usually located near the tip, is designed to securely attach the decking material (such as wooden boards or composite decking) to the underlying support structure (such as joists or beams). This threading provides a strong and reliable connection, ensuring that the decking boards are firmly anchored in place.

The unthreaded portion, found closer to the screw head, serves multiple purposes:

  1. Prevents Over-Driving: The unthreaded section helps prevent the screw from being driven too deeply into the decking material, which could lead to damage or splitting.
  2. Countersinking: It allows the screw head to sink flush with or slightly below the surface of the decking material, creating a smooth and safe walking surface.
  3. Reduced Splitting: The absence of threads in this section reduces the likelihood of the decking material splitting, which can be a concern when fastening near the board’s edges.
Full thread screw

Full Thread

Unlike partial thread decking screws, which have a combination of threaded and unthreaded sections, full thread decking screws have threads that extend along the entire length of the screw shaft.

The key features and uses of full thread decking screws include:

  1. Secure Fastening: The continuous threading along the entire shaft provides a strong and secure connection between the decking material (such as wooden boards or composite decking) and the underlying support structure (such as joists or beams).
  2. Enhanced Grip: The full thread design allows the screw to grip the wood or composite material more effectively, reducing the risk of boards coming loose over time.
  3. Reduced Splitting: Consistent threading can help minimize the likelihood of the decking material splitting when the screw is driven in, especially near the edges of the boards.
  4. Versatility: Full-thread decking screws are suitable for a wide range of decking materials and installation scenarios.

Screw head types for decking boards

Decking screws typically use a specific type of screw head that is designed to provide a secure and flush installation while also being resistant to corrosion. The two most common types of screw heads used for decking are:

square drive deck screw head

Square Drive (Robertson) Head

Square drive screws are very popular for decking applications. They have a square-shaped recess in the screw head, and the corresponding driver (bit) has a matching square shape. This design offers excellent torque transfer, reducing the risk of the driver slipping or stripping the screw head. Square drive screws are known for their ease of use. They are less likely to cam out (slip out) during installation, making them a reliable choice for deck construction.

Star head decking screw

Torx (Star) Head

Torx screws feature a star-shaped recess in the screw head. The corresponding driver has a matching star shape. Torx screws are known for their high torque transfer capability and resistance to camming out. They provide a secure and flush installation, which is particularly important for decking projects. The Torx design also helps prevent driver wear and ensures a reliable connection.

Both square drive and Torx heads are excellent choices for decking screws because they offer secure fastening, reduced risk of stripping, and resistance to corrosion when made from appropriate materials or finishes (such as stainless steel or coated screws). When selecting screws for your decking project, make sure to choose the type of head that you are most comfortable using with your preferred screwdriver or drill bit.


The longevity and performance of your timber deck are intricately tied to the choice of decking screws. Therefore, taking the time to carefully consider the factors discussed in this blog can help you make an informed decision.

If you are working on a decking project or you are thinking of building a deck, get in contact with us soon. We supply top-quality pine timber decking and a range of hardwood decking. Furthermore, we also supply the screws and all the other products you may need to build a complete timber deck. Send us an email with your requirements and we’ll get back to you soonest.

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