But there are forms of bracing other than knee bracing that do provide lateral stiffness. This would be lateral bracing.
Lateral bracing is a technique employed in much of Europe, it employs long slanted braces interfacing with horizontal and vertical timbers. For this to work, you must have either a studded timber frame, such as in the English or French styles, or a relatively close posted timber frame with horizontal ties, such as in the German style. I don't know much about the English (I assume it would achieve the same properties) but the Germans say that by having long braces pass over the horizontal members, they achieve a tremendous amount of lateral stiffness. Having the verticality of a cavity interrupted by one or more horizontal ties does a tremendous job of stiffening the structure against wind loading (that in combination with the Windrispen, very long roof braces that cross many rafters and tie them together) The Germans do all this, because they teach that you should rely on the enclosure -be it it boarding or infill- for absolutely nothing other than keeping out the cold. They have also striven to make frames which are very stiff and rigid.
I imagine that having long braces that pass from one bent to the next, with a few studs in between, would do the same thing.
Whenever you have vertical members that can brace against other vertical members, it improves the stiffness of the whole assembly. Vertical members braced against horizontal members is a flexible assembly. The same is true of Horizontal members braced against other horizontal members.
Alternately, you could build the frame as normal, and as part of a modified Larsen-Truss or similar enclosure method include very long 2x4 braces nailed diagonally across the frame, crossing over many of the studs thus tying them together.
The American timber frame is a flexible design, likely designed to be flexible. Keep in mind though that other cultures designed their frames to be as stiff as they could get them.
By enclosure the frame in typical manners you are essential doing the same thing I am suggesting here, tying many vertical members to each other to achieve stiffness. Sheathing can do a decent job of achieving lateral stiffness, I won't say much for relying on it for keeping things square...
Last edited by D L Bahler; 02/25/11 07:51 PM.
