More in Framing

Creating Half-Lap Joints

Mill your own quickly and easily using nothing more than a portable circular saw and a chisel

Half-Lap
Illustration by Narda Lebo

Half-lap joints are commonly used when building with framing lumber, especially on long runs and for 90-degree intersections. They keep the mating surfaces flush and the wood thickness uniform. Although there are several ways to cut a half-lap, here's how to quickly mill one using nothing more than a portable circular saw and a chisel:

Clamp two boards side by side with their ends even. Measure a distance in from the ends that's equal to the width of one board, and mark a square line across both boards. Set the depth of cut on the saw to half the thickness of the boards and make a cut along the line to form the shoulder of the joint.

Next, cut a series of closely spaced saw kerfs across the boards. Use a chisel to clear away the waste wood and smooth out the broad, flat surface of the joint. Unclamp the boards and put them together cheek to cheek to form a 90-degree angle.

Then assemble the joint. The method of assembly depends on the thickness of the boards and the size of the completed frame. Typically, frames built with 2-by lumber or thicker require mechanical fasteners.

1 ×

Quick Half-Lap Joints

 

Quick Half-Lap Joints

Quick Half-Lap Joints
Illustration by Narda Lebo

Cut a series of closely spaced saw kerfs across the boards.

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Half-Lap

 

Half-Lap

Half-Lap
Illustration by Narda Lebo

Use a chisel to clear away the waste wood.

 
 

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