Two-Part Crown
When Wendy and I began a project to install two-part crown moulding in the dining room of our 1910 Foursquare, we knew to expect wavy plaster walls and an inconsistent ceiling height. To help us identify problem areas and create consistent install lines, we created two templates, or jigs. Then we hit on the idea of creating a level line using a laser.
The first jig was a mockup of the two-part crown itself: a large piece of cove moulding mounted on a flat piece of backer board with a beaded edge.
Only the bottom inch or so of the backer would show beneath the cove moulding.
Since we intended to install the backer boards first, followed by the cove moulding, we needed a marker to set the reveal. I cut a representation of the reveal that allowed us to set a pencil line where the bottom of the backer board should fall, keeping it more or less level around the room. This allowed us to force the crown up or down as we went, for a consistent exposure.
To keep everything level, we used a laser line that showed where the bottom of the backer should sit— essential, since the ceiling and walls are wavy, not square and plumb. Mounting the laser was surprisingly easy: I screwed a piece of metal from leftover ductwork to the beam, then used magnets from the laser level hous
ing to position it as needed. The laser line let us see where we needed to fudge the backer up or down, in an attempt to split the difference where the ceiling was too out of whack.
When we began the install—working around the room clockwise—we
discovered that it made more sense to install sections of backer and crown, working only one or two sections ahead, rather than installing all the backer at
once, followed by all the crown. We also learned to not fully nail down the backer until finishing up the previous crown. This let us test-fit the next crown.
To measure long runs, we used a small 30' pocket laser distance measurer to get our cut lengths. It’s more accurate and much easier than a tape measure, especially for lengths of 10' or more.
One mistake we didn’t make this time was installing the crown all around the room without leaving space for the final backer board at our return to the starting point. Without proper spacing, we’d need to cope the final backer piece into the first piece of crown—awkward to say the least. To leave room, I held a loose piece of backer perpendicular to the first backer board and gave myself a pencil line to indicate where the crown should start. The last backer board slid into place behind the first crown.