TASK 5 GRADED TIMBER Structural grading of timber is the process by which it is assigned into different stress grades (groups), the timbers within each group should have similar properties. However due to the nature of timber there is inevitably a substantial range of properties within each grade and also an overlap in properties between grades, graded timber is stamped in accordance with The Timber Research and Development Association (TRADA) guidelines. Structural grading can be performed in