When you think of timber frame homes, you think of the smell of the timber, the big open spaces, and the natural beauty, but you also admire the craftsmanship spent making high quality, super strong structures. The building blocks of all timber frame homes is the carefully cut timber, but the joinery is what shapes them. Your child might refer to joinery as, “What snaps the legos together.”
We take pride in the quality of our craftsmanship at Woodhouse. While some companies machine cut and others hand cut timbers, we do both, using machine-cut joinery with a CNC machine for accuracy, competitive pricing, and efficient production, and hand finishing for superior quality and beauty.
A Time-Tested Building System
Joinery is an essential part of woodworking and the time-tested technology has been passed down through out the ages. Chris Koehn, the Western Regional Project Manager at Woodhouse, started his Timber Framing career in Germany restoring a medieval city with his uncle who was a restoration carpenter.
“Pulling a timber frame out of a building and realizing that the man who put it in there has been dead for 500 years or more was an interesting feeling… by studying these ancient structures, you learn what works and what doesn’t work,” said Chris.
Chris believes that the differences between European and Northern American Joinery techniques are mainly driven by the size of the trees Northern America had available when settlers first arrived. Europe ran out of large timbers long ago and had to compensate with smaller timbers.
“You don’t see any buildings in Europe post 1500AD that had any long, straight timber in it. They had to put together smaller pieces of timber and their joinery had to change to accommodate that,” said Chris.
While Europe was using Timber Framing for all sorts of structures, Northern Americans primarily used the building system to create wide open barns.
Northern Americans modified their frame lay-out system to efficiently use the larger North American timber for bigger, more repetitious buildings. We see this tradition continue even today in many of our “bent” based frame designs.
How Joinery Works
Fred Dewey, a Senior Designer and Joinery Expert at Woodhouse, describes joinery as, “The intersection between two or more timbers to form both a strong and aesthetically pleasing connection.”
Types of Joinery
A true timber frame structure uses many types of joinery. The 3 most common types of joinery in post and beam structures are:
- Mortise and Tenon joints – These joints have adjoining pieces that connect at an angle, which help transfer loads from horizontal timbers to vertical timbers. They typically have a 45° diagonal piece called a brace or strut that helps stabilize the beams. They are pegged, as opposed to nailed or screwed, and can be stronger than lap joints which use nails or screws.
- Lap joint – A joint made with two pieces of metal, timber, etc., by halving the thickness of each member at the joint and fitting them together. These joints are used on outside corners or where beams intersect, and are commonly nailed or screwed. You do not typically find lap joints used in historical European structures because steel for nails was a limited resource.
- Dove tails – A flaring lap joint which fits tightly making an interlocking joint between two pieces that resists pulling apart in all directions except one. These are used for special modifications to structures and works well for a high tension application. You typically would find this joint at a collar tie or joist location.
Systems for Creating Joinery
Europeans cut the timber used to create joinery by using a system called “scribing,” where you hold one timber up to another and hand-cut the pieces to match up perfectly. All of the joints are unique to the size of the timbers and can’t be used interchangeably throughout the structure.
Northern America adapted a lay out technique called square rule, which allowed for repetitious buildings like barns that have the same cuts of timber in a bunch of locations. It allowed for us to build bigger structures faster, but essentially functions the same way.
This timeless technology for joining wood is one reason Woodhouse’s timber frame structures are so appealing. It is a form of craftsmanship that makes the structure strong, while remaining hidden to stay beautiful to the eye.