C16 VS C24 – What’s the difference?

One of the most common questions we get from customers is the difference between C16 and C24 timber.

If you're unsure which to choose, the team at North West Timber Treatments is always here to help!

Strength and Durability

C16 is a graded timber suitable for general construction. It is durable enough for most domestic & commercial applications but not as strong as C24.

C24 is a higher grade timber with greater strength and durability, ideal for more demanding structural applications.

Density and Knots

C16 contains more knots and defects, which can impact its strength and appearance.

C24 has fewer knots and defects, making it stronger and more aesthetically pleasing.

Source

C16 is typically sourced from fast-growing trees, often from regions with a milder climate like the UK.

C24 is usually sourced from colder climates, such as Scandinavia, where slower tree growth produces denser and stronger wood.

Applications

C16 is ideal for internal construction like floor joists, roofing, and non-load-bearing applications.

C24 is usually preferred for internal, external and load-bearing structures where strength does not want to be compromised.

Cost

C16 is more affordable due to the lower grading requirements.

C24 is more expensive due to its superior strength and quality.

Appearance

C16 has more visual imperfections.

C24 has a smoother finish and is more visually appealing for exposed applications. (But not a joinery product)

Which one should you choose?

Choose C16 for cost-effective projects where high strength isn't necessary.

Opt for C24 when you need superior strength, durability, or a cleaner aesthetic for visible timber.