Wooden frames have always suffered from the weather, so the joinery industry has always looked for new and better protective coatings for wooden structures. Now research is focusing on pre-treating the wood instead. Borrowing technology from the car industry, the process involves passing wood over a flame in a strictly controlled environment. The flame does not burn the wood or change its appearance, but it alters the surface chemistry. After this treatment, liquids behave differently when they come into contact with the wood. Protective coatings, when applied to wood that has been treated, should bond with the wood better and resist weathering more effectively. Tests on different types of wood have found that the treatment is most effective with oak and beech. Because the process is simple and cost effective, it is easy to add to an existing production line. The improvement that can be made in the quality of wood could see such technology becoming widespread in the joinery industry.