Crown molding is a common trim upgrade that can really make a room pop. You can easily create elaborate cornices by combining different pieces of molding for a “built-up” look. It’s a great way to get more from less, but it’s also a common way to make a clean wall look muddy.
Lucky for us, there are rules for molding that were literally carved in stone a long time ago. This article draws on those tried-and-true forms to present three design rules for crown molding.
A quick review of the classic architectural tradition shows unity and harmony of parts. The ancients viewed the human body as the model for design. Just as hands, feet, arms, and legs are proportionally related, so too in ancient buildings are the parts related to one another—both in style and proportion.
Your forearm is 1.6 times longer than your hand; each knuckle on your fingers is 1.6 times larger than the previous one. This 1:1.6 ratio is called the Golden Ratio, and the ancients used it as the basis for rules of architectural proportion.
Crown molding on a wall corresponds to part of the cornice of a column. But you can’t measure the diameter of a wall, so you have to back-calculate that dimension to determine the ideal height of a crown molding. For a 96-inch-tall wall, the formula is:
96 = Base (½ D) + Shaft (6 D) + Capital (½ D) + Architrave (½ D) + Frieze (½ D) = 8 D
D = 96 ÷ 8 = 12 inches
For the Tuscan order, the cornice (¾ D) should be about 9 inches tall.
There are other orders, too, and the moldings that are used to make the various parts is not a crap shoot. They are predictable.
White space matters. Notice how many flat-plane surfaces make up the entablature in the illustration above. These flat surfaces are not places where the ancients forgot to add profiles—they are deliberately inserted and play a purposeful part in the overall design.
Moldings are a language. They communicate and have personalities. Really. Try to visualize the flat-plane areas as pauses, or breaks, between words in a sentence. Insteadoftalkingreallyfastandnotpausingtotakeabreath.
The flat areas help our eyes read the moldings and understand what they are saying.
RULE 3: More contour is worse, not better
Over the last 20 years, molding—and especially crown molding—has morphed and mutated into silly, bumpy masses, often shaped with haphazard bellies, bruises, corners, and angles, all meant to look like many moldings were used. Some builders have begun to use two heavily figured moldings to make a crown look like it has six or seven smaller pieces—to make up a “masterful” cornice at a fraction of the cost.
Bad crown molding is like an avalanche of dips and turns—except that avalanches follow the golden ratio, too.