What is checking and how does it affect the strength of the timbers?
As timber dries the changes in it s dimensions, during drying, are not equal in all directions. The difference in girth and diameter shrinkage rates induces tension stress that cause lengthwise separation of the wood. There are several ways in which checking can be minimized by either removing the heart of the tree from the timber (free of heart timbers), by using recycled timber, by using standing dead or by using air dried or kiln-dried timber. Checking and shrinkage are primarily aesthetic problems not structural. The only time checking would be of structural concern would be if a check extends clear through a timber. Since the timbers, typically used in Timber Frame construction, are similar in depth as they are in width, the checks typically do not extend through the timbers. If for some reason a check extends through a timber our Structural Engineers can recalculate the structural capacity, of the checked timber, to determine if remedial repairs are required. Our Structural Engin
