How to Install Crown Molding (First-Timer's Guide)

Crown molding intimidates DIYers because the corners look impossible. A coping saw and one secret jig setup makes it manageable.

Crown molding sits at an angle between ceiling and wall — usually 38° (or 45° for some profiles). On your miter saw, the molding must be held upside-down and backwards, with the ceiling edge flat on the saw base. Buy a set of crown stops ($15) to hold the angle consistently; trying to eyeball it never works.

For inside corners, don't miter both pieces. Cut the first piece square (butting into the corner), and cope the second piece — cut a miter, then use a coping saw to remove the back, leaving a profile that matches and overlaps the first piece. Coped joints look perfect even when your corners aren't exactly 90°.

For outside corners, you have to miter — but cut a test piece first to check the actual angle, because almost no corner is precisely 90°. Adjust the saw by 1° at a time until the joint closes tight.

Nail with a 16 or 18 gauge brad nailer into the top plate (ceiling side) and into studs (wall side). Don't expect to nail every spot into framing — caulk fills the gap between molding and uneven walls, and that's normal. Caulk and paint hide a multitude of first-timer sins.