What are considered defects of timber.

Each state has its own code regarding Timber Defects for construction use. As an example, Pennsylvania's code includes knots or "Cross-grained wood in which the fibres are not parallel with the axis or longitudinal edge of the piece".

Source / Read more about Pennsylvania's Code on Timber Defects (http://www.pacode.com/secure/data/034/chapter21/s21.11.html)

You can look for your state's code on Timber Defects, or, tell us where you live and we will try to find it for you. Thank you for asking your question here on our site.