For a single chandelier centered over the table, choose a lighting fixture with a diameter half the width of the tabletop. For example, a rectangular table that is 48 inches wide requires a chandelier with a diameter of 24 inches. A circular table with a diameter of 40 inches needs a chandelier that is 20 inches in diameter.
For a very large dining room table, some homeowners opt for two chandeliers. In this case, choose fixtures that are one-third the width of the dining room table. A table that is 60 inches wide, for example, would need two 20-inch-diameter fixtures. Each chandelier should be centered over its half of the table.
The height of the chandelier should be determined by the height of the dining room ceiling. Designers allow 2 1/2 to 3 inches of chandelier height for each foot of room height. A room with typical 8-foot ceilings, for example, should have a chandelier that is 20 to 24 inches tall. A room with a 10-foot ceiling could carry a 25- to 30-inch-high fixture.
When placing the chandelier, it should hang 30 to 36 inches above the tabletop. This allows the chandelier to cast a warm glow on the diners without obstructing their view of each other. It also leaves plenty of space for flower arrangements, candles and tall serving pieces. Hang the chandelier directly over the center of the table, even if it is not the center of the room.
When choosing a lighting fixture for over a dining room table, other factors sometimes come into play regarding its size. Style and heaviness of the chandelier can affect the size needed. if a chandelier has a very heavy look, the size requirements can be scaled down somewhat. Conversely, if a fixture is very delicate and slender, size requirements may be scaled up.