The Story
Treated C24 sawn timber 47mm x 225mm x 6.0m is a kiln dried, pressure treated structural softwood graded to BS 4978 for use in demanding load-bearing applications. Its generous depth makes it particularly well suited to floor joists, rafters and structural frames where longer spans or heavier loads are specified.
Specifications
| Property | Detail |
|---|---|
| Material | Structural softwood (spruce/pine/fir) |
| Treatment | Pressure treated, kiln dried to 20% MC or below |
| Grade | C24 to BS 4978 |
| Finish | Sawn |
| Nominal Size | 47mm x 225mm |
| Length | 6.0m |
What it's used for
- Floor joists in new-build and renovation projects where wider spans require a deeper section
- Roof rafters and ridge construction on domestic and commercial buildings
- Structural wall frames, stud work and load-bearing partitions
- Engineered structural carcassing where C24 is specified by a structural engineer or building control
Fitting and handling
Allow the timber to acclimatise on site for at least 24 to 48 hours before fixing, keeping it off the ground and covered to maintain its moisture content. Use joist hangers, structural screws or galvanised nails suitable for treated timber, as standard bright-steel fixings can corrode when in contact with the preservative salts. Store flat and supported at regular centres to prevent bowing before installation.
FAQ
What is the difference between C16 and C24 treated timber?
C24 has a higher bending strength and stiffness than C16, meaning it can carry greater loads or span longer distances for the same section size. Where a structural engineer or building regulations require C24, substituting C16 is not acceptable without recalculating the design.
Is this timber suitable for ground contact?
Pressure treatment provides good protection against rot and fungal attack in exposed or high-humidity environments, but this product is not rated for direct, prolonged ground contact. For posts or sleepers set into soil, choose a timber with a Use Class 4 treatment rating.
Can I cut the treated timber on site without reapplying preservative?
Yes, site cutting is normal practice. Apply an approved end-grain preservative or treatment solution to any freshly cut surfaces, particularly at joints and notches, to maintain protection at those points.
Browse the full range of C24 graded timber at Nottage Timber Merchants. We supply trade and retail customers across South Wales, with next-day delivery available to the Bridgend area and competitive rates on larger structural orders.
Description
Treated C24 sawn timber 47mm x 225mm x 6.0m is a kiln dried, pressure treated structural softwood graded to BS 4978 for use in demanding load-bearing applications. Its generous depth makes it particularly well suited to floor joists, rafters and structural frames where longer spans or heavier loads are specified.
Specifications
| Property | Detail |
|---|---|
| Material | Structural softwood (spruce/pine/fir) |
| Treatment | Pressure treated, kiln dried to 20% MC or below |
| Grade | C24 to BS 4978 |
| Finish | Sawn |
| Nominal Size | 47mm x 225mm |
| Length | 6.0m |
What it's used for
- Floor joists in new-build and renovation projects where wider spans require a deeper section
- Roof rafters and ridge construction on domestic and commercial buildings
- Structural wall frames, stud work and load-bearing partitions
- Engineered structural carcassing where C24 is specified by a structural engineer or building control
Fitting and handling
Allow the timber to acclimatise on site for at least 24 to 48 hours before fixing, keeping it off the ground and covered to maintain its moisture content. Use joist hangers, structural screws or galvanised nails suitable for treated timber, as standard bright-steel fixings can corrode when in contact with the preservative salts. Store flat and supported at regular centres to prevent bowing before installation.
FAQ
What is the difference between C16 and C24 treated timber?
C24 has a higher bending strength and stiffness than C16, meaning it can carry greater loads or span longer distances for the same section size. Where a structural engineer or building regulations require C24, substituting C16 is not acceptable without recalculating the design.
Is this timber suitable for ground contact?
Pressure treatment provides good protection against rot and fungal attack in exposed or high-humidity environments, but this product is not rated for direct, prolonged ground contact. For posts or sleepers set into soil, choose a timber with a Use Class 4 treatment rating.
Can I cut the treated timber on site without reapplying preservative?
Yes, site cutting is normal practice. Apply an approved end-grain preservative or treatment solution to any freshly cut surfaces, particularly at joints and notches, to maintain protection at those points.
Browse the full range of C24 graded timber at Nottage Timber Merchants. We supply trade and retail customers across South Wales, with next-day delivery available to the Bridgend area and competitive rates on larger structural orders.
