How to measure a lamp post globe or street lamp to buy a replacement?
After 15 years in business, one of the most common questions we receive from customers is how to order the right size globe. In order to get the right sized globe for your needs, there are a few things that you need to know.
The best way to determine the diameter of a globe is to measure around the globe with a flexible measuring tape. This measurement will give you the circumference of the globe, and you can then divide that number by 3.14 (Pi) to get the diameter. If you don't have a flexible measuring tape, you can insert a ruler up through the opening to the top of the globe. This will give you a rough estimate of the diameter. However, keep in mind that for neckless globes, it is important to note that the vertical diameter will be less than the horizontal diameter. This is because the cut at the bottom removes some of the diameter. This will have an impact if you need a certain amount of clearance to accommodate the height of the bulb inside. The diameter of our globes come in even numbered increments (eg. 10 inch, 12 inch, 14 inch, etc.)
For acorn shaped globes, or other non-round shapes, measure the globe at its widest part. This will give you the circumference of the globe. Then divide the circumference by pi or 3.14 to get the diameter.
The next bit of information that you need is the size of the flange or opening at the bottom of the globe. Generally, flange sizes are determined by the outside edge of the flange. Place a ruler across the opening of the globe at its widest. The outside diameter of the flange will slightly less than the size of the fitter. For instance, a 12 inch globe with a flange diameter of 3.91 inches is made to fit a 4 inch fitter.
Often the globe is broken or missing, and the customer has to guess at the size of the globe. In these situations, the most important piece of information is the inside diameter of the fitter. Simply place a ruler across the fitter at the widest part and measure the inside diameter of fitter.
If you have any questions or concerns about ordering the right-sized globe for your application, please call 800-665-3594 or email us at [email protected]