Fixing and buying guide
2.4Mtr X 47 X 100mm (4" x 2") C24 Treated Regularised KD Carcassing Timber
Selecting the right size
This 47 × 100mm section is a standard carcassing size suitable for floor joists, roof battens, stud walls, and decking frames. The 2.4 metre length offers flexibility for most domestic and light commercial applications. Consider your span requirements and load conditions when determining whether this section meets your structural needs. For longer spans or heavier loads, you may need to increase the section size or reduce spacing between supports.
- 47 × 100mm is a common section for residential floor joists and wall framing
- 2.4 metre length suits standard room widths and allows for waste
- Check your building design or structural engineer's specification for exact section requirements
Understanding C24 grading
C24 is a strength grade that indicates this timber has been visually or machine-graded to meet specific structural performance standards. C24 timber offers enhanced stability, fewer knots, and improved strength compared to lower grades such as C16. This makes it suitable for applications where reliable load-bearing performance is essential.
- C24 grade provides superior strength and stiffness for structural work
- Fewer defects and knots compared to C16 timber
- Meets BS EN standards for structural timber grading
Pressure treatment and durability
This timber is pressure-treated with preservative to protect against rot, fungal decay, and insect infestation. The treatment penetrates the timber to provide long-term protection, making it suitable for both indoor and outdoor use. Treated timber is particularly valuable in damp environments or where timber may be exposed to weather.
- Preservative treatment protects against rot and fungal decay
- Resistant to insect attack, including woodworm and termites
- Suitable for outdoor applications and damp locations
- Treatment extends the service life of the timber significantly
Moisture content and handling
This timber is supplied kiln-dried (KD), meaning it has been dried in a kiln to reduce moisture content. Kiln-dried timber is more stable, less prone to warping, and easier to work with than green timber. Store it in dry conditions and allow it to acclimatise to the building environment before installation to minimise movement.
- Kiln-dried timber has lower moisture content for improved stability
- Less likely to warp, twist, or cup compared to air-dried timber
- Store under cover and allow acclimatisation before fixing
- Protect from rain and excessive moisture during storage and installation
Ordering and stock considerations
When ordering, account for waste and cutting losses in your calculations. Standard lengths like 2.4 metres are commonly stocked, but availability may vary. Order slightly more than your calculated requirement to allow for defects, cutting, and fitting adjustments. Check with your supplier for current stock and delivery lead times.
- Add 5–10% to your calculated requirement for waste and adjustments
- Confirm availability and delivery timescales with your supplier
- Consider whether you need multiple lengths or can work with standard 2.4m pieces