Scale

To determine the proper diameter for your room, first measure the room’s length and width in feet, and add those numbers together. So, if the room is 10×12, your number would be 22. Swap the unit from feet to inches (so, 22 inches), and that is your correct diameter. Remember, this isn’t a hard and fast rule, but it is a good guideline to make sure your light looks right in the space.

Next, you need to figure out the height of light fixture that will look best in your space. Start by measuring the height of the room, from floor to ceiling. Multiply the height by 2.5-3, to get a range. So, if the room is 10″ tall, your new measurement is 25-30″. Again, swap that value for inches (25-30′) and you’ll find the ideal height of light fixture for this particular room.

Functional Guidelines

Diameter and height are basic measurements that don’t take furniture into account. But, designers have a few guidelines to help place light fixtures in context with their surroundings. For rooms where people might be walking under a fixture, keep 7 feet of clearance from the bottom of the fixture to the floor. In an open hallway or a foyer, hang chandeliers and pendants at least six inches higher than the door.

For light fixtures over a table, you’ll want to make sure the fixture is at least a foot shorter than the table, and at least 6 inches narrower. That way, your fixture won’t overpower the tabletop itself. In terms of height, hang lighting between 28-36 inches above the tabletop.

A kitchen island also demands good lighting, and the spacing should be slightly different. Typically pendants hang 28-34 inches above the counter, or 72 inches above the floor. You’ll want to space them equally over the countertop, but a good rule of thumb is to hang them roughly 30 inches apart.