Installing an air conditioning unit can ensure your home stays cool during the hottest months. With an abundance of models available, it can be overwhelming to decide which one you should buy. To narrow your choices, start by determining the unit size your home needs. Here’s a quick guide to help you understand what factors affect the size requirements and how to determine the size you’ll need.

Factors to Consider

The British thermal unit (BTU) indicates an air conditioner’s cooling power. Generally, every 1,000 square feet requires around 18,000 BTUs for maximum efficiency.

air conditioning unitMeasure the square footage of the space you want to cool. If your unit is only meant for one space, find the area’s square footage by multiplying the room’s length by width. Repeat these calculations for each room and hallway if you plan to cool your entire home with the same unit.

Consider your home’s location. Houses at sea level may require a unit with more BTUs than residences at a cooler, higher altitude. Additionally, increase the BTUs if the unit’s room has south-facing windows because more sunlight will stream through the glass, warming the space. Lastly, you may need a stronger system if the room has heat-generating appliances, like an oven or printer, that affect the indoor air temperature.

Types of Air Conditioning Units

Window units possess cooling capacities that range from 5,000 to 12,500 BTUs and are best for cooling individual rooms and homes up to 700 square feet. Central air conditioners are measured in tons, with 12,000 BTUs equal to one ton. Most central home units range from one and a half to five tons.


If you need help calculating how many BTUs your home’s air conditioning unit should have, contact the experts at Cool It Kauai Air Conditioning in Kapaa, HI. Their reliable, certified technicians are available 24/7, and they’ll help you choose the appropriate AC unit for your house. After installation, the team will maintain the unit by performing routine repairs and inspections. View their services online, or call (808) 315-1888 to schedule an appointment.