The Proportion Rules Designers Use

Rooms that feel right usually follow a handful of proportions, whether or not anyone measured. Designers keep them as rules of thumb because they work more often than not, and because breaking one on purpose is easier when you know where it is.

The two-thirds rule for width

Art above a piece of furniture looks right at two thirds to three quarters of the furniture’s width. Over an 84 in (213 cm) sofa that is 56 to 63 in (142 to 160 cm); over a 60 in (152 cm) queen bed, 40 to 45 in (102 to 114 cm); over a 66 in (168 cm) mantel, 44 to 50 in (112 to 127 cm). Narrower and the art looks timid, wider and it crowds the furniture’s ends. A pair or trio counts as one width, gaps included.

The same rule loosely governs height: keep the art to about two thirds of the wall between the furniture and the ceiling.

60-30-10 for a room’s colors

The 60-30-10 rule divides a room’s color roughly into three:

• About 60 % for the main color, usually the walls and the largest pieces of furniture.
• About 30 % for a second color: upholstery, curtains, a rug.
• About 10 % for an accent: cushions, a vase, a lamp.

A painting usually supplies the 10 %, or part of the 30 %. That is a useful way to choose one: a painting whose strongest color is the room’s accent ties the scheme together, and one whose main color is the room’s second color makes it feel deliberate. A painting that brings a new color in, used in no other place in the room, becomes the room’s accent on its own, which is fine for one painting and confusing for three.

70/30 for balance

The 70/30 idea is a composition rule of thumb that painters and decorators both use. Let one thing dominate roughly 70 % of a picture or a wall arrangement, one color family, one value, or calm empty space, and keep about 30 % for contrast. It is why a painting that is mostly quiet blue-gray sea with one red sail reads as balanced, and why a wall of mostly black-and-white prints can carry a single color photograph.

In practice it helps in two places. Choosing a painting, a picture with one dominant mood and a smaller counterpoint tends to sit more easily in a room than one that is half one thing and half another. Arranging a group, mostly similar frames with a few different ones looks planned; half and half looks undecided.

Odd numbers for groups

Groups of three or five look more natural than pairs of pairs, because the eye settles on a middle. A trio above a sofa, five small frames up a short wall, three objects on a mantel. Pairs are the exception: a matched pair is formal and symmetrical by design, and it suits a bed with two lamps or the two sides of a doorway.

Leave room to breathe

Negative space, bare wall around a picture, is part of the composition. Leave at least a hand’s width, 4 to 6 in, between a large work and anything near it: a window frame, a door casing, a shelf, the ceiling. A painting squeezed into a gap looks like storage; the same painting with room around it looks chosen. On a gallery wall the gap between frames is smaller, 2 to 3 in, because the group is the picture.

Using them together

Start with width, because it rules out the most. The art size calculator applies the two-thirds rule to your furniture and lists the print sizes in range. Then use color: decide whether the painting should echo the room’s main color, provide its accent or sit neutral, and let the wall color matcher sort the paintings that way. Finally check the balance and the breathing room on the wall itself; a paper template taped up for a day settles most doubts. The living room and bedroom collections show these rules at work, each painting in a mock-up drawn to scale.