4x2 Timber C24 Joist, Pressure Treated Timber 47x100mm - 3.0m

4x2 Treated Timber Joists measure 47x100mm (approx finished size of 45x95mm) and are 3m long. Made from responsibly sourced timber of high quality from FSC certified forests, these joists are kiln dried to ensure straightness and strength and treated for moisture and pest resistance.

• FSC Certified Timber
• Kiln Dried for additional strength and durability
• Regularised for uniform size, with eased corners
• For use in exterior and structural applications
• Conforms to BS 4978 and EN 14081:2006
• Graded to C24 strength grade

What is 4x2 Timber in mm?

The term "4x2" signifies the joist size in inches. The metric equivalent of 4x2 Timber measures 47 x 100mm. Due to the regularisation of the timber ensuring uniformity throughout its length, the "finished" size might be slightly smaller, typically around 45mm x 100mm, to maintain consistent dimensions along its length.

The size difference is minimal and in the vast majority of projects will make no difference to your project, and is standard across 47x100, 4x2 regularised timber joists.

What are 4x2 C24 Timber Joists Used For?

Regularized 4x2 timber joist is one of the most widely used timber joist sizes. They have many applications, with the strength making them a popular choice for constructing decks, garden buildings, and featuring prominently in the walls, roofs, and floors of timber-frame structures.

What is Regularised Timber?

Many of our  timber joists are referred to as “regularised” - this means that lengths of timber are machine-finished to achieve a smooth finish and a uniform thickness and width along the length of the timber joist. This can impact the finished size of the product by a few millimetres. The most common types of regularised timber joists are C16 and C24.

What Does Kiln Dried Mean?

Kiln Dried Timber undergoes a kiln drying process, by being placed in kilns where a consistent heat removes excess moisture from freshly cut boards. This method reduces weight, enhances strength and straightness, and improves its workability. Contrasting with the lengthy air-drying process that can span several months to a year, kiln drying is notably faster.

What Lengths Do 4x2 C24 Timber Joists Come in?

We provide both treated and untreated regularised 4x2 timber joists in a range of sizes: 2.4m, 3m, 3.6m, and 4.8m. While we strive to maintain stock across all sizes for delivery, there might be instances where you could receive a longer length as an alternative due to delay or unavailability of specific sizes in your region.

What Does C24 Stand For?

In the UK, regularised timber typically falls into one of two grades: C16 or C24. The "C" designates the type of wood, in this instance, Conifer. The numeric value signifies the strength classification determined by various factors like imperfections, knots, etc., with C24 considered the stronger grade between the two.

Primarily, C16 timber joists are used in numerous wall and roofing applications, whereas C24 is preferred for instances demanding notably high strength, such as roofing and flooring joists.

Do I Need Treated 4x2 Timber?

For projects facing potential moisture or pest exposure, it's recommended to choose 4x2 treated timber. These timbers undergo pressure treatment, ensuring the treatment penetrates the wood, offering long-lasting protection against rot and pests. This choice is particularly suitable for outdoor projects like decking, roofing, and other similar endeavors