What is Green Oak Timber?

Green oak timber refers to unseasoned oak that is freshly cut, hence the term ‘green’. It is typically cut within 3 to 18 months after the tree is felled, and retains a high moisture content. Green oak frames are commonly used as the primary structure of a building, rather than steel or masonry, formed with beams, posts, braces, and trusses.

The components are joined with traditional carpentry techniques, such as pegged mortise-and-tenon or dovetail joints. Whilst green oak can be expensive it is cheaper than seasoned oak, as this type of wood is air dried or kiln dried therefore has additional costs involved, whereas green oak will dry over time in its final location.

What new buildings suit Green Oak Frames?

Oak frames can traditionally span up to around 7 meters, making them ideal for open-plan layouts. This is why they were historically used in barns and are now an excellent solution for modern homes, swimming pool houses, garden rooms, and extensions. The frames offer architects flexibility in layout design, as they can be infilled with non-load-bearing materials such as timber, brickwork, or even straw bales to form walls.

New buildings are typically constructed with oak frames for their aesthetic appeal; the natural beauty of oak provides a warm, organic look that pays homage to historical architecture. When sourced from sustainably managed forests, green oak timber is also a truly renewable resource, an important consideration for many clients.

What are the structural characteristics of Green Oak?

Oak is a hardwood, known for its superior strength and durability, as evidenced by historic oak frames that have lasted for centuries.

When oak is green, it has a high moisture content, typically around 20% initially. As the moisture content reduces to about 12%, the wood becomes harder and stronger, but it also shrinks and develops splits. This natural distortion is why it is crucial to work with architects and engineers who are experienced with oak and its unique characteristics. For example, they can design structural connections that “tighten up” as the wood dries. Whether for residential homes, commercial buildings, or historical restorations, our team offers expert timber structural engineering solutions for green oak frame projects.

If you are considering using green oak for your build, don’t hesitate to get in touch, you can call our Romsey office on 01794 524447 or email [email protected]