If you live in an attic apartment, it may be warm and toasty during the winter, but when summer rolls around, you are likely to find it sweltering. A window air conditioner may be the answer to keeping your attic apartment cool. Here's what you need to know about buying the right air conditioner for your attic apartment.

How Do You Know What Size AC Unit You Need?

You need an air conditioner that is the right size for the area. This is one of those times when bigger isn't always better, as an air conditioner that is too large for the area will waste energy. Here's how to find the right size air conditioner for your attic apartment.

  1. Measure the  width and length of each room in your apartment. If you live in an efficiency or open loft, you can measure the entire floor space as one room.
  2. Write the numbers in feet, using a decimal for portions of a foot. For example, if your room is 7 foot 6 inches wide, write it as 7.5 feet.
  3. Multiply the width times the length of the room to get the square footage of the room. For example, if your room is 7.5 feet wide and 9 feet long, multiple 7.5 times 9 to get 67.5 square feet.
  4. Add the square footage of each room together to get the total square feet of the area to be cooled.
  5. Multiply the square footage by 35 to determine the number of BTUs you will need to cool the area, says Enlightenme.com. It also recommends adding 10% to the BTUs for a sunny room, which may be comparable to an attic apartment.  Adding the 10% to the number of BTUs will help compensate for the additional heat your attic apartment gains from the floors below. To add 10%, multiply the number of BTUs by .10 and add this number to the total BTUs. Air conditioning units are rated by BTU. This number should be clearly printed on the label.

How Do You Know if It Will Fit in Your Window?

Attic apartments often have odd shaped or non-standard sized windows. It is important to measure both the height and width of  the window you intend to use for your air conditioning unit. Many window units come with expandable plastic window guards to block the area around the base of the air conditioner if the unit is smaller than the window opening. However, if your window is smaller than a standard window, it may not be large enough to accommodate a standard window air conditioning unit. Standard window air conditioners come in two versions. Units for slider or casement windows measure approximately 14 inches wide and 20 inches high, while those for double hung or cottage windows measure between approximately 12 to 20 inches high and 18 to 26 inches wide. You may need to purchase an air conditioner made specifically for small windows if your attic windows do not match these dimensions. If the windows in your attic apartment are located under the eaves, they may also be installed horizontally, or even on a slant, instead of vertically. This may also affect the fit of your air conditioner. 

If the AC Unit Doesn't Fit, Can You Install It Sideways?

You may have seen this done before or have a buddy who tells you it is fine, but the truth is, installing a window air conditioner on its side is dangerous business. The unit may fall, causing damage to the property, or it may short out. If you must install a window air conditioner on its side because of the size or shape of your attic apartment windows, contact a HVAC contractor to do it for you. He can make the necessary adaptations, add additional braces outside the window and check that it is safe to operate in this position. He also has the ladders and equipment needed to access the unit from the outside to install braces.

What Other Choices Are There?

If your attempts to find a window air conditioner that will fit into the windows in your attic apartment don't work out, there is another option. You can purchase a portable air conditioner for your apartment. The downside to this option is that the moisture from the AC unit drains in a catch basin that must be emptied frequently. Depending on the size of the unit, the temperature and the humidity levels in your region, you may need to empty the basin more than once a day.

Choosing an air conditioner that is the right size for your attic apartment and that fits into your window properly will keep you more comfortable during the heat of summer. For more information and help, contact a local HVAC company like Century Heating & Air Conditioning Services