Window air conditioners are available in a wide range of sizes and shapes.
When you measure a window for an air conditioner, you also need to determine the size of the room, the power source and how to secure the unit in the window.
Once you have established the square footage and window size, you can peruse the multitude of air conditioners that will fit in the window and provide sufficient cooling power for the space. Decide which window will hold the air conditioner. On the north side or the shady side of the house is best. You don’t want the unit to extend over a sidewalk where a passerby might walk into it. You also may need to take extra measures to secure the unit so no one can access your home by removing the air conditioner and climbing through the window. Open the window. Using a tape measure, measure the opening side to side and top to bottom. Write down the measurements and measure a second time to be sure you have the correct number. Look at the type of window and determine whether it is a casement, sliding horizontal, single hung, double hung, or louvered style. Measure the square footage of the room as well. The length multiplied by the width determines the square footage. To determine the BTU’s of a unit to get, multiply the square footage by 30 if it’s a shady room on the ground floor or by 40 if it’s in the kitchen, or an upper floor. Use the measurements of the window and size of the room to decide which window AC will best suit your needs. In addition to the size of the unit, check the outlets. Most homes only have standard 120w volt outlets, and older homes may not have a three prong outlet. You may need a three prong extension cord rated for use with an air conditioner. Last, check the energy star ratings for the air conditioner to determine the energy use of the unit.