What is CLS timber?

In construction and woodworking, one term that frequently emerges is CLS timber. Understanding this foundational material is essential whether you’re a seasoned builder or a DIY enthusiast. In this blog post, we will delve into the world of CLS timber, shedding light on its properties, applications, and what makes it a preferred choice in the United Kingdom.

We’ll also explore the factors influencing CLS timber prices and discuss the crucial question: What is CLS timber treated with? So, join us on this journey as we demystify the secrets of CLS timber in the UK, empowering you with the knowledge you need to make informed decisions for your projects.

What is CLS Timber Used for

CLS (Canadian Lumber Standard) timber is a specific type of timber commonly used in construction and woodworking projects. It is primarily known for its versatility and strength, making it suitable for various applications. Here are some common uses of CLS timber:

1. Stud Framing: CLS timber is often used as framing material in construction. It is employed to create the skeletal structure of buildings’ walls, partitions, and ceilings. Its uniform size and straightness make it ideal for creating stable and reliable frameworks.
2. Internal Walls: CLS timber is frequently used for constructing inner walls in homes and commercial buildings. Its dimensional stability and ease of handling make it a popular choice for creating partition walls to divide interior spaces.
3. Door and Window Frames: CLS timber makes door and window frames. Its straight and smooth surface allows for precise cutting and shaping, ensuring that doors and windows fit securely in their openings.
4. Furniture Building: Woodworkers and furniture makers often use CLS timber to create various pieces of furniture. Its strength and relatively low cost make it an attractive choice for crafting tables, chairs, cabinets, and more.
5. Roof Trusses: CLS timber can be used for roofing applications to construct roof trusses or rafters. Its strength and reliability are essential for supporting the roof’s weight and providing structural integrity.
6. Garden and Outdoor Projects: CLS timber is famous for outdoor projects such as constructing fences, decking, pergolas, and garden sheds. Its durability and resistance to decay, when properly treated and maintained, make it suitable for enduring various weather conditions.
7. DIY and Renovation: DIY enthusiasts often choose CLS timber for their home improvement projects due to its ease of use and availability. It can create shelving units, framing, and other structural elements.
8. Temporary Structures: CLS timber is sometimes used to construct temporary structures like scaffolding and shoring due to its strength and cost-effectiveness.

Is CLS Timber Waterproof?

CLS timber is not inherently waterproof. It is a type of softwood timber, typically made from spruce or pine, and these types of wood are naturally susceptible to moisture absorption and decay when exposed to wet conditions over an extended period. However, the water resistance of CLS timber can be significantly improved through treatment and proper maintenance.

Here are some key points to consider regarding the waterproofing of CLS timber:

1. Treatment: CLS timber can be treated with preservatives to enhance its resistance to water and decay. Common treatments include pressure treatment using chemicals like copper-based compounds. This treatment process forces preservatives into the wood, making it more resistant to moisture and pests. Treated CLS timber is often labelled as “treated” or “pressure-treated” and is suitable for outdoor applications where it may come into contact with water.
2. Sealing: For certain applications, such as building outdoor structures like decks or fences, it’s recommended to seal or finish CLS timber with appropriate wood sealants, stains, or paints. These coatings create a protective barrier on the surface of the wood, preventing water from penetrating and causing damage.
3. Maintenance: Even treated CLS timber and sealed wood require ongoing maintenance to ensure water resistance. This may involve periodic resealing, repainting, or reapplying preservatives, especially in outdoor applications where the wood is exposed to the elements.
4. Limitations: While treated and sealed CLS timber can resist water significantly, it is essential to recognize that no wood product is entirely waterproof. Prolonged exposure to standing water or continuous moisture can still lead to degradation over time.

What is CLS Timber Made Of?

CLS is a type of timber that is primarily made from softwood lumber. In some regions, it is also known as “whitewood”. The softwood used to make CLS timber can be of different types, but the most common ones are spruce (Picea) or pine (Pinus) wood. These types of softwood are readily available in North America and other parts of the world, and they possess several desirable properties for use in construction and woodworking applications.

Here are some key characteristics of the softwood species often used to make CLS timber:

1. Spruce (Picea): Spruce wood is known for its straight grain and uniform texture. It is lightweight yet strong, making it suitable for framing and structural applications. Spruce is also relatively easy to work with, allowing precise cutting and shaping.
2. Pine (Pinus): Pine wood is also commonly used in CLS timber. It is known for its availability and affordability. Pine has a pale colour and a straight grain pattern, making it a versatile choice for various woodworking projects. It is also relatively lightweight and easy to work with.

CLS timber is typically processed and milled to specific dimensions, resulting in uniformly sized and straight-edged lumber. “CLS” often refers to lumber that has been planed and eased at the edges, giving it a smooth and finished appearance. The standard dimensions for CLS timber vary by region and supplier, but it is commonly available in sizes like 38mm x 63mm or 38mm x 89mm (width x depth).

It’s important to note that while CLS timber is made from softwood, its properties can vary based on the wood’s moisture content, treatment, and grading. For construction and woodworking projects, it is essential to choose CLS timber with the appropriate grade and treatment to ensure it meets the structural and durability requirements of the application.

CLS timber is typically made from softwood species like spruce and pine, valued for their strength, workability, and availability. These softwoods are processed and milled to specific dimensions and often undergo treatment to enhance their durability and resistance to decay and pests.

Is CLS Timber Suitable for Outside?

CLS timber can be suitable for outdoor use, but its suitability largely depends on various factors, including the wood’s treatment, environmental conditions, and how it’s used. Here are some considerations regarding whether CLS timber is appropriate for outdoor applications:

1. Treatment: Untreated CLS timber is not recommended for outdoor use, as it is susceptible to moisture absorption, decay, and insect infestation. However, CLS timber can be treated with preservatives through a process known as pressure treatment. This treatment involves forcing preservative chemicals into the wood, making it more resistant to moisture, rot, and pests. Treated CLS timber is suitable for outdoor applications and is often labelled as “pressure-treated” or “treated timber.”
2. Environmental Exposure: The environment in which the CLS timber will be used is crucial. If the wood will be constantly exposed to rain, snow, or soil moisture, it’s essential to use treated CLS timber. Even treated wood may require periodic maintenance, such as resealing or repainting, to ensure long-term durability.
3. Use and Location: Consider the specific outdoor application and its location. CLS timber is commonly used for outdoor structures like decks, fences, garden sheds, and pergolas. It can also be used for framing exterior walls. However, in these applications, it’s vital to use treated CLS timber to protect it from moisture-related damage.
4. Proper Installation: Proper installation techniques are essential to ensure the longevity of CLS timber in outdoor settings. This includes using appropriate fasteners (like galvanized or stainless steel screws and nails) and adequate ventilation to prevent moisture buildup.
5. Regular Maintenance: Even treated CLS timber will benefit from regular maintenance. This may involve reapplying wood preservatives, sealants, or paints to maintain its resistance to moisture and UV radiation. Proper care can significantly extend the lifespan of outdoor CLS timber.

What Is the Price of CLS Timber?

The price of CLS timber can vary depending on the specific dimensions, quality, brand, and purchase location. Based on the data you provided from Buildiro.com, here are some price examples for different CLS timber sizes:

1. CLS – 2400mm x 75mm x 50mm (3in x 2in): This size is available for £4.28 per piece.
2. Wickes Studwork CLS Timber – 38 x 89 x 2400mm: A larger size, this CLS timber is priced at £6.95 per piece.
3. Wickes Studwork CLS Timber – 38 x 63 x 2400mm: This slightly smaller size is available for £3.45 per piece.

It’s important to note that prices can vary based on the size and factors such as the supplier, geographic location, and market conditions. Additionally, prices may change over time due to fluctuations in the cost of materials and other economic factors.

To get the most accurate and up-to-date pricing for CLS timber, it’s advisable to check with local lumber suppliers, home improvement stores, or online retailers. Different suppliers may offer varying prices and provide bulk discounts for larger quantities of timber. When planning a project, obtaining multiple quotes is a good practice to ensure you get the best value for your specific needs.