When you invest in an oak-framed building, what you don’t see is just as important as what you do. Behind every beautifully crafted frame is a carefully specified structural system designed to perform reliably for decades.
At English Heritage Buildings, we supply precision-made, bespoke green oak and Douglas fir frames alongside high-quality, strength-graded structural timber and treated external materials. These are all selected to support longevity, safety, and peace of mind.
What We Offer You
- Structural softwood carcassing timber, supplied as standard to C24 grade
- Treated softwood weatherboard, prepared for external use
- Consistent quality control, including professional timber grading
What is Carcassing Timber?
Carcassing timber is the structural softwood used behind the scenes of a building. While it’s not always visible once construction is complete, it plays a crucial role in strength, stability, and long-term performance.
You’ll typically find carcassing timber used for:
- Roof structures and rafters
- Floor joists
- Internal wall structures (studwork)
Because this timber supports the building structure, its strength and treatment are essential, which is why we specify it carefully.
Our Standards for Softwood Carcassing Timber
All softwood carcassing supplied by English Heritage Buildings is C24 strength-graded and professionally treated with Vacsol Aqua preservative, using a double-vacuum pressure process, to help protect it for the long term. This process is designed to support a service life of 60 years or more.
To maintain this level of protection, we also apply end-grain treatment to all cut timber before it leaves our workshop. This ensures vulnerable cut ends are protected and helps preserve the integrity of the treatment.
A Note: Cutting or machining timber after treatment can reduce the effectiveness of the preservative, which is why preparation before delivery matters.
Our Softwood Weatherboard
In addition to structural timber, we also supply softwood weatherboard where required, treated with Axil 3000P, a water-based wood preservative. This treatment helps improve durability and suitability for external use, supporting long-term performance when correctly installed and maintained.
What Does “Graded Timber” Mean?
Timber grading is a process used to assess the strength and suitability of timber for structural use. Grading standards are set out by the British Standards Institution, and timber is assessed against clear criteria to ensure it can safely perform its intended role.
During grading, factors assessed include:
- Signs of woodworm
- Knots
- Splits along the grain
- Grain direction
C16 vs C24 Timber
When researching a building project, you may come across references to C16 and C24 timber. Both are commonly used structural grades of softwood, but they are suited to different applications depending on strength, appearance, and performance.
C stands for “conifer”, the type of tree that the timber comes from, while the 16 and 24 refer to the strength grade.
What is C16 Timber?
C16 timber is one of the most widely used grades in the UK construction industry. It offers good structural strength and is commonly used for internal applications such as wall studs, floor joists, and roof structures.
Because C16 timber can include more natural variations, such as grain deviations or cosmetic markings, it is typically more cost-effective. These visual characteristics don’t prevent it from being used structurally, but they do mean the timber is less consistent in both appearance and overall strength compared to higher grades.
What is C24 Timber?
C24 timber is a higher-grade structural timber, offering greater strength and consistency than C16. It is kiln-dried and carefully graded to ensure fewer defects, resulting in a more uniform appearance and improved structural performance.
This higher quality is often achieved because the timber comes from slower-grown trees, which produce a tighter grain structure. The result is timber that is stronger, more resilient, and better suited to applications where performance and longevity are especially important.
Due to these qualities, C24 timber typically comes at a higher cost, but it also provides greater reassurance when used in demanding structural roles.
Quality You Can Rely On
Every element we supply is chosen to support the same goal: to create oak-framed buildings that are built properly, perform reliably to modern expectations with traditional standards, and stand the test of time.
Our approach combines:
- Clear, upfront specification
- Over 30 years of experience
- Professional timber grading
- Consistent manufacturing processes
Learn More or Speak to an Expert
If you’d like to explore further details or understand how this applies to your own project, you may find some of our other guides and services helpful. Request a brochure or find out what’s included in your quote right here on our website, or get in touch with us online or over the phone.
Whether you’re planning an oak-framed garage, garden room, extension, or bespoke building, our team is here to help you move forward with confidence.
