What is CLS timber? 

CLS stands for 'Canadian Lumber Standard,' as it was originally manufactured in Canada. Initially CLS was used for constructing resilient timber-framed homes and structures, it has since gained global popularity.

CLS timber originates from wood species like kiln-dried fir, pine, or spruce. The intricate manufacturing process involves planing, treatment, and regularization through mill machinery.

The result? A meticulously shaped timber with four smoothed surfaces and those recognizable rounded (or radiused) eased edges.

What are the KEY benefits of CLS Timber?

When considering using CLS timber for your project, it's worth considering the KEY benefits of CLS Timber:

  • Strength and Durability: CLS timber's exceptional strength and remarkable durability set it apart from other wood varieties. It excels in construction tasks, including internal structural elements like stud walls and partitions.
  • Ease of Handling: Thanks to its rounded or eased edges, CLS timber is notably easy to transport and handle safely, making your construction process more efficient.
  • Fire-Resistant Properties: With minimized knots along its edges, CLS timber possesses attributes that contribute to the suppression of potential fire outbreaks, enhancing safety.
  • Customization and Efficiency: CLS timber comes in various widths and lengths, allowing for reduced cutting time and minimizing timber wastage, leading to cost savings.


Where is CLS Timber best used?

This versatile timber finds its home in a variety of internal structural projects. Beyond its inherent strength and durability, its symmetrical shape and softened edges make it ideal for tasks like:

  • Constructing timber-framed residences
  • Creating internal partition walls
  • Framing interior spaces
  • Building stud walls
  • Undertaking carcassing projects

Regarding strength grading, you'll come across two categories for CLS timber: C16 and C24. While they share a visual resemblance, C24 boasts superior structural integrity, often reflected in its pricing.

Can you use CLS Timber outside?

Should your project involve outdoor use, it's crucial to remember that CLS timber is suitable for exterior applications only if it has undergone pressure treatment with protective chemicals. The treatment equips it to withstand external climate conditions and help to avoid issues such as rot, mould, and decay.

Is CLS Timber aligned with your project vision?

Here at Frank Key, our inventory boasts an extensive collection of CLS timber in a variety of sizes and lengths, all readily available for purchase. Rest assured, our commitment to sustainability remains dedicated as ever. If you encounter difficulty in finding the exact match for your needs, a simple call to our experienced sales team is all it takes. They're enthusiastic about providing guidance and assistance for all your timber enquiries. Call us if you require any assistance: 0115 920 8208