Why is “green” wood used for timber frames?

Timber frames have traditionally been built using green timber – meaning timber that has a high moisture content because it has not been sufficiently air dried or kiln dried. There are several reasons for this tradition: As wood dries it become more difficult to work. Green timber is easier to work with chisels, and other hand tools. Stockpiling timbers until they dry would take two to four years. Most people are not willing to wait years for a timber frame. As green wood dries out it shrinks. We allow for this shrinkage in our design and joinery. As the frame dries, the type of joints we use maintains their tightness. All medieval and new world timber frames used the same type of joints we employ.

Timber also dries and shrinks in cross-section. This results in checking, and will always happen when a timber looses moisture too quickly. The checks do not pose a problem structurally. We help slow the drying process by sealing the end grain of our timbers. We also recommend that the frame not be heated and dried out excessively for one year after it is raised and enclosed. It can be slowed further by not keeping the house too hot and dry during the first year of occupation.

 
 
Tom Musco, the founder and principle timber framer of Royalston Oak, began his professional woodworking career as a musical instrument apprentice to Peter S Kyvelos in Belmont, Massachusetts in 1973. Tom spent several years making and repairing a variety of Middle Eastern and Western stringed musical instruments. One of his dulcimers was featured in the first Fine Woodworking Design Book in 1976. Tom and his wife Judy moved to Royalston, Massachusetts in 1977 and began building timber frames, an interest he discovered in a beautiful timber-frame barn on his in-laws farm in Petersham, Massachusetts. His first frame was for his shop and his second frame was for his house. He made furniture and timber frames until 1980 when his shop was struck by lightening and burned to the ground along with all his tools and machinery. He built a new timber framed shop with the help of his neighbors and began timber framing full time. Tom was a founding member of the Timber Framers Guild. He has done workshops in NE ( Pembroke workshop at TFG ) and England. In 1989 Tom and his crew participated in the famous Concord Barn Raising episode of This Old House. He has built timber frames in New York State, the Hamptons, Tennessee, North Carolina, Alaska, and all the New England states except Rhode Island. Tom has crafted almost 200 timber frames since 1977. Tom is also an excellent cook with an interest in food of Sicily, where 3 of his 4 grandparents were born. He has written a series of articles on Sicilian food which you can read at the website of the Umass Journalism in Sicily Program.