How to Choose a Lamp Shade Size
- 1). Measure the lamp from the bottom edge of its base to the top of its stem to calculate its height. You'll want to choose a lamp shade with a bottom diameter that is within 2 inches, plus or minus, the measured height of your lamp.
- 2). Determine the best diameter for your lamp shade. An ideal lamp shade will measure within 2 inches (plus or minus) of the height of the table lamp. For an 18-inch table lamp, use a lamp shade with a bottom diameter of 16 inches, 17 inches, 19 inches or 20 inches. The diameter measures how long the bottom part of the lamp shade extends from side to side.
- 3). Decide the best height for your lamp shape. As a general rule of thumb, according to antiquelampsupply.com ("Antique Lamp Supply"), "The overall height of the shade is directly related to the height of the harp and should be no more than ½ inch (plus or minus) taller or shorter than the total height of the harp." Measure from the metal wire located just below the socket to the tip of the lamp (an area known as the harp). For example, a 9-inch harp would ideally require a lamp shade that is 8 1/ 2 to 9 1/ 2 inches in height.
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