The True North Patented Keylock Air Seal Corner®

Step A	Log 1 is ripped in half at the factory to be laid on the concrete foundation or subfloor. Two butyl tapes and one asphalt impregnated foam tape are applied to the top of log 1 in the patented tongue and groove channels referred to on the preceding page. True North pre-drills a 1-1/8” hole in the centre of the log as shown in red. A second hole is drilled on the inside face of the log as shown in blue. When the dovetail is cut, part of the hole shown in red, is removed.
Step B	The bottom groove of log 2 is removed at the factory to lay flat on the concrete foundation or subfloor. The patented polypropylene keylock is cut in half. The top half of the keylock is driven into the inside face of Log 1, shown in blue. An asphalt foam corner gasket is applied to the top of the dovetail on Log 1. The red hole in log 2 drops over the half keylock in log 1. The inside face of log 1 is now keylocked to log 2, creating an airtight seal.
Step C	When the faces of Logs 1 and 2 are brought together the blue and red holes create a figure 8 shape. A full size keylock is driven into the inside face of Log 2, (blue hole) which pulls this face into the side of Log 1. (red hole).
Step D	Another asphalt foam corner gasket is applied to the top of the dovetail on Log 2. The red hole in Log 3 is dropped over the keylock in Log 2.
Step E	Logs 2, 3, and 4 are now keylocked together at the interfaces. The green arrows show the direction in which Logs 1 and 3 are pulled into Logs 2 and 4 internally by the keylocks. Log 1 and 3 will shrink to logs 2 and 4 over time.
Step F	On top of Log 2, butyl tape and asphalt foam tape are again set into the tongue and groove channels. Another keylock is now driven into the inside face of Log 3, which pulls this face into the side of Log 2. A third asphalt corner gasket is applied to the top of the dovetail on Log 3. The red hole in Log 4 is now dropped over the keylock in Log 3.
Step G	Logs 2, 3, and 4 are now keylocked together at the interfaces. The green arrows show the direction in which Logs 1 and 3 are pulled into Logs 2 and 4 internally by the keylocks. Log 1and 3 will shrink to logs 2 and 4 over time. The sequence continues through each course to the top of the log wall. After the top log is applied a spring loaded thru-bolt is installed.
True North’s Keylock Air Seal Corner® (exclusive to True North)	True North’s Secret True North’s patented keylock, when inserted, pulls the log interfaces together. Over time the log shrinks towards the keylock ensuring an airtight seal. True North’s Philosophy True North uses the naturally occurring shrinkage in the width of the log to its fullest advantage making the corner tighter (as shown with green arrows).
	*Systems shown and used by True North Log Homes Inc. are protected by patents and patents pending - U.S.A. and Canada.