From what I've seen the most common timber frame woods are Red and white oak, Eastern White Pine and Southern Yellow pine. Movnig up the cost scale they use Doug Fir from up North, and Some use reclaimed redwood out west. In the old days, Hemlock was used in many barns and structures. I read some opinions though that it tends to check and twist more than is desireable. Maybe the old growth stuff didn't as much, not sure. As far as posts go, my interpretation from being on this site in the last 10 months and the forestry forum, is that hey if it held up the tree it should hold up the frame. As long as there are no obvious problems, even knotty spruce can be used for posts it seems. For tie beams, rafters, and basically the rest of the frame you need a high grade material. Members that will be in tension or experience bending stresses need to be more uniform and not have defects that would compromise the strength on bending and shear.
Not sure about soft maple, but I'm guessing that some of the others can be used, provided you have good strength numbers for the species and their specific strengths are used in calculations for the joint stresses. Heck the honey locust is used for fence posts, I'm thinking it's got to be pretty good in a frame? Part of the consideration is going to be how those mateials, in beam form, will dry. If huge checks open up that would compromise the structrual integrity, well... Checks are normal when beams dry, but it's how big and their positioning that determine whether your calculations are compromised or not. Now we need someone to respond with direct experience with using these types of wood. You should also probably go check out and register on the forestryforums.com website if you have not already. It's another great resource.
Last edited by brad_bb; 09/13/07 06:48 PM.
