How to Measure for a New Lamp Shade

It's funny how one thing leads to another--the beautiful fresh coat of paint on your walls has just made it crystal clear that it's time to replace old lampshades. Or, perhaps the gorgeous lamp base you found at the antique store has everything you need to pull your new decorating scheme together, except a shade. Communicating well with your lighting specialist means knowing a few common terms that determine the fit of a new lamp shade. Follow the steps below to take the measurements you need to get the perfect new shade.

Things You'll Need

• Old lamp shade, if you have it Lamp base Harp, if available Measuring tape Paper Pencil

Instructions

Measuring the Shade

1. Take the following measurements of your lamp shade: top diameter, bottom diameter, depth, slope length. The top diameter is measured from one edge to the opposite edge, across the spider. The spider is the crisscross metal frame on the top of the shade with a ring or a lightbulb clip in the middle . That's the piece that will connect the shade to the lightbulb or the harp. While you are measuring the top diameter, notice whether the spider sits flat across the top or dips down inside the shade. If it dips down inside (is recessed), measure how deep it goes--usually an inch or two. You can note this: top diam. 6 inches, spider recessed 1 1/2 inches. Measure the bottom diameter--for example, bottom diam. 8 inches.

2. Measure the depth of the shade. On a drum shade (top and bottom diameters are the same or very close--the whole thing is shaped like a drum), the depth and the slope length are the same. Measuring down the straight side gives you a depth of 10 inches; this is the slope length, too. On the shade described in Step 1, the shade is somewhat flared (looks like an upside down ice cream cone with the point cut off). It's hard to measure straight top to bottom for depth. Run your measuring tape down the side (follow the seam in the shade if it has one). This, for example, might come to 11 inches; measuring straight up and down would give you a depth of 10 inches, but the more accurate slope length is 11 inches, and that's what your specialist needs to know. Tell her that you measured the slope length, and your shade is 6" (top) by 11" (slope) by 8" (bottom).

3. Tell your specialist if the spider is flat or recessed (and by how much). If your lamp has a harp, measure that, too. The harp is the metal loop that connects to the bulb socket and comes up over the lightbulb. The harp might be 6, 8, 10 or 12 inches high. The harp determines, along with the spider, exactly how high the shade sits on the lamp. If your lamp looks as though it's hiding under its shade, maybe the harp is too short. If the harp is too tall, your lamp will look like a growing boy in last year's pants.

4. Add any other details that may affect your choice. If your shade has (or you want) a scalloped edge or fringe, measure that too. Now, you're ready to find a beautiful new shade for your lamp.