What is the difference between C16 Timber and C24 Timber

Much like other building materials, timber is available in a range of different varieties, each of which offer their own unique properties and advantages. 

This ensures that your timber is precisely engineered to suit your specific project, and secures the best possible end results. 

In this article, we’ll be taking a look at two common grading classifications of timber – C16 and C24 timber. 

Keep reading to find out more about the differences between C16 and C24 timber, and their respective recommended uses.

What is the difference between C16 and C24?

The main differences between C16 and C24 timber are their strength and quality. 

Carcassing timbers are graded, in accordance with standards outlined by the BSI (under the BS 5268 guidelines). These standards grade a board based on its durability (which is measured by assessing characteristics such as the grain slope, and any wormwood holes or knots). 

The letter ‘C’ in this grading system stands for ‘conifer’. Then, the following number denotes the timber’s strength grade. The higher the number, the higher the strength and quality of the wood. 

There are 12 timber strength grades in the BS 5638 standards. But, C16 and C24 are two of the most commonly used timber grades. 

What is C16 Timber?

Building Uses

The minimum strength of C16 timber is 16 N/mm². 

C16 timber is a type of softwood, typically fir, pine or spruce. 

Although it is not as high quality as C24 timber, C16 timber is still of a sufficient quality to be used in building projects. In fact, it is widely used in construction projects, including roofing, flooring, internal stud walls and joists. Typically, it is used for internal construction projects (due to its lower strength). 

Benefits

• A more affordable material than C24 timber. 
• Widely available, and can easily be purchased from most timber suppliers. 
• For many projects, C16 is still of sufficient durability, strength and quality. Although it is of a lower strength than C24 timber, C16 timber is suitable for use in a wide range of standard, non-load-bearing projects.

What is C24 Timber?

Building Uses

The minimum strength of C24 timber is 24 N/mm². 

C24 timber is a premium softwood (typically pine or spruce), which has a higher strength, durability and resilience than C16 timber. 

As the timber has fewer knots and imperfections, C24 timber is widely used in projects that require high-strength timber. In fact, C24 timber is one of the highest quality timber types available. 

As a result, it is widely used in the construction of heavy-duty flooring, load-bearing joists and beams, wall framing, roof structures, and other load-bearing projects. 

Benefits

• Higher strength and durability 
• Greater structural integrity
• Able to withstand harsh conditions, and more weather-resistant 
• Fewer knots and visual defects, making it more visually attractive 
• Straighter, making it easier to use in construction  
• Can also be used for outdoor projects (when weather-treated)

At Planet Timber, we are specialist timber merchants. From our Chesterfield base, we supply clients across the country with a wide range of timber materials and accessories, including both C16 and C24 timber.

If you have any further questions about these varieties of timber, or are unsure which timber you should choose for your project, don’t hesitate to get in touch.