Fitting extension jambs to the irregular walls of older homes can be time-consuming. Faced with this task, I get out my veneer saw. First, I rip the extension jambs slightly wider than necessary. Holding a jamb in place with one hand, I slide the saw along the wall so that its teeth scribe a line on the back of the extension jamb, as shown in the drawing. A veneer saw’s teeth have no set, so they will not mar a finished wall, and the serrated cutting edge is not so apt to wander with the grain the way a knife edge would. Next, I use a plane to trim down to the scribe line at a 3° bevel so that the inside edge of the jamb will stand slightly (and properly) proud of the wall.
Steve Becker, Valatie, NY
Edited and Illustrated by Charles Miller
From Fine Homebuilding #58
