The Story
C24 regularised sawn timber in a 47mm x 100mm (4x2) section is a strength-graded structural timber kiln dried to 20% moisture content or below. Graded to BS 4978, it is well suited to load-bearing frames, floor joists, and roof structures where reliable, consistent performance is required.
Specifications
| Property | Detail |
|---|---|
| Material | Softwood (regularised sawn) |
| Grade | C24 to BS 4978 |
| Finish | Regularised (planed all round, eased corners) |
| Nominal Size | 47mm x 100mm (4x2) |
| Finished Size | Approximately 45mm x 95mm |
| Lengths | 2.4m (8ft), 3.6m (12ft), 4.8m (16ft) |
| Moisture Content | Kiln dried to 20% or below |
| Profile | Sawn, regularised |
What it's used for
- Floor joists and timber floor cassettes in new-build and renovation projects
- Roof rafters, ceiling joists, and ridge board framing
- Stud partitions and load-bearing timber frame walls
- General structural carcassing where C16 grade is not sufficient
Fitting and handling
Allow the timber to acclimatise on site for at least 48 hours before fixing, keeping it stacked flat and off the ground on bearers under cover to prevent movement or distortion. Fix using structural ring-shank nails, joist hanger nails, or M10 bolts with washers depending on the application, and follow current Building Regulations Part A and any relevant engineer's specification for span tables and fixing centres. Store any unused lengths flat, supported at regular intervals, and away from direct moisture to maintain the kiln-dried condition.
FAQ
What is the difference between C16 and C24 structural timber?
C24 has a higher bending strength and stiffness rating than C16, making it suitable for longer spans or heavier loads. Where a structural engineer or Building Control specifies C24, C16 cannot be substituted without reassessment.
Is 47mm x 100mm C24 timber the same as 4x2?
Yes. The 4x2 description refers to the nominal imperial size of 4 inches by 2 inches. The metric equivalent is 47mm x 100mm nominal, finishing at approximately 45mm x 95mm after regularising.
Does this timber come pressure treated?
The timber listed here is kiln dried and graded but not pressure treated. If you need preservative-treated C24 for ground-contact or exposed conditions, please contact Nottage Timber Merchants directly to check availability.
Browse the full range of C24 graded timber available from Nottage Timber Merchants in Bridgend. We supply trade and self-build customers across South Wales, with next-day delivery available to the Bridgend area and beyond.
Description
C24 regularised sawn timber in a 47mm x 100mm (4x2) section is a strength-graded structural timber kiln dried to 20% moisture content or below. Graded to BS 4978, it is well suited to load-bearing frames, floor joists, and roof structures where reliable, consistent performance is required.
Specifications
| Property | Detail |
|---|---|
| Material | Softwood (regularised sawn) |
| Grade | C24 to BS 4978 |
| Finish | Regularised (planed all round, eased corners) |
| Nominal Size | 47mm x 100mm (4x2) |
| Finished Size | Approximately 45mm x 95mm |
| Lengths | 2.4m (8ft), 3.6m (12ft), 4.8m (16ft) |
| Moisture Content | Kiln dried to 20% or below |
| Profile | Sawn, regularised |
What it's used for
- Floor joists and timber floor cassettes in new-build and renovation projects
- Roof rafters, ceiling joists, and ridge board framing
- Stud partitions and load-bearing timber frame walls
- General structural carcassing where C16 grade is not sufficient
Fitting and handling
Allow the timber to acclimatise on site for at least 48 hours before fixing, keeping it stacked flat and off the ground on bearers under cover to prevent movement or distortion. Fix using structural ring-shank nails, joist hanger nails, or M10 bolts with washers depending on the application, and follow current Building Regulations Part A and any relevant engineer's specification for span tables and fixing centres. Store any unused lengths flat, supported at regular intervals, and away from direct moisture to maintain the kiln-dried condition.
FAQ
What is the difference between C16 and C24 structural timber?
C24 has a higher bending strength and stiffness rating than C16, making it suitable for longer spans or heavier loads. Where a structural engineer or Building Control specifies C24, C16 cannot be substituted without reassessment.
Is 47mm x 100mm C24 timber the same as 4x2?
Yes. The 4x2 description refers to the nominal imperial size of 4 inches by 2 inches. The metric equivalent is 47mm x 100mm nominal, finishing at approximately 45mm x 95mm after regularising.
Does this timber come pressure treated?
The timber listed here is kiln dried and graded but not pressure treated. If you need preservative-treated C24 for ground-contact or exposed conditions, please contact Nottage Timber Merchants directly to check availability.
Browse the full range of C24 graded timber available from Nottage Timber Merchants in Bridgend. We supply trade and self-build customers across South Wales, with next-day delivery available to the Bridgend area and beyond.
