Why does Seasoned Oak split?
What causes shrinkage and splitting?
11th March 2024
Seasoned Oak is timber that has been cut and left to dry for 1 or more years in a natural environment, with full exposure to the elements. During this time the moisture leaves the timber and therefore causes shrinkage and splitting.
Medullary rays and knots are rigid features in Oak and won’t move with the rest of the timber – this is the main cause of splitting. The less knots in the timber, the cleaner (less splits) the timber will be. Splits naturally occur and cannot be avoided.
If a smaller section is dried slowly and carefully in a controlled environment, it will split but the split will fuse back together after a time. However, the natural features of Oak such as heart and knots, will always cause splitting whatever drying process is undertaken.
After 1 year of seasoning, most if not all moisture in the timber will have dried out and therefore movement will be minimal. This is why Seasoned Oak beams and lintels are ideal for applications where movement must be kept to a minimum, such as mantelpieces, ceiling joists and more!
