Timber framing was the most common form of wooden house building until milled, dimensional lumber had been developed.
Houses are built from large timbers, sometimes as much as 12-inches square, that are placed together using interlocking joints that are held by wooden pegs. Traditional timber frames do not use nails or other metal fasteners.
Mortise and Tenon
The most basic joint that is used in timber framing is a mortise and tenon. A mortise is a hole that is cut into the side of the timber, and the tenon is the end of the piece of timber that will fit into that hole.
Once the tenon is fitted into the mortise, holes are drilled that go through the wood surrounding the mortise and through the tenon. Pegs are hammered into the hole to secure the two timber pieces together.
Bents
Timber-framed houses will have a roof supported by bents. A bent is one section of timber framing that is put together into an integral unit and then lifted into place using a crane or something similar.
Diagonal bracing
One of the defining characteristics that can be seen in timber-framed barns and homes is the element of diagonal bracing. Diagonal braces, built into the corners where posts meet joists, help to keep the angles square and to strengthen the joints.
Braces can be made using straight timbers, but can be more decorative when put together using naturally bent pieces of wood.
The braces are secured to posts and joists using mortise and tenon joints. The joists that support a ceiling are often left exposed in timber-framed homes in order to show off the natural beauty of the wood.