Has your home been feeling a bit like Goldilocks lately? Too hot in summer, too cold in winter, and never just right? Despite leaving windows open or throwing a door snake under the front door, getting the temperature just perfect in your home can be a little challenging (even at the best of times). If you’ve decided to install an air conditioner in your home and have been asking yourself, “What size mini split do I need?” you’re definitely not alone. Let’s take a look at the specifics you’ll need to know to ensure your home always feels just right all year round.
1. Measuring Up: Your First Step to Comfort
The road to the perfect temperature at home starts with the humble tape measure. You’ll need to start by calculating the square footage of each room you want to heat or cool.
Simply measure the width and length of each room, then multiply these numbers together. For example, a room that is 20 feet long and 15 feet wide has a square footage of 300 square feet.
Calculating how much space you’ll need to cool and heat is the first step to answering the question“What size mini split do I need?” but there are a few other factors to consider.
2. Beyond the Numbers: What Other Factors Influence Size?
Square foot measurements tell part of the story, but not the whole saga. There are some other elements around the home that can influence what size mini-split system you’re going to need:
- Insulation Quality: A well-insulated home retains the heat in winter and keeps the cool air inside during summer. If your home has poor insulation (or none at all), your system is going to be working harder.
- Window Types and Placement: Ever wonder why homes up north have double, or even triple-glazed windows? The more panes of glass windows have, the more stable the air temperature inside the home.
- Climate: Flagstaff, AZ, enjoys a semi-arid climate, meaning there is a huge variation between summer and winter temperatures. In our neck of the woods, split systems have to work much harder to keep the temperature at home stable.
Keep these factors in mind when estimating the size of the mini-split system you’re going to need.
3. The BTU Breakdown: Matching System Capacity to Need
The capacity of a mini-split system is measured in British Thermal Units or BTUs. A single BTU is enough energy to raise the temperature of one pound of water by one degree Fahrenheit.
In much simpler terms, the more BTUs a system has, the more heating and cooling it is capable of.
Have those square foot measurements handy? Below, we’ve made a table that will match your room size to a mini-split BTU capacity:
| Room Size (sq ft) | Required BTUs |
| 150 to 250 | 6,000 BTUs |
| 250 to 300 | 7,000 BTUs |
| 300 to 350 | 8,000 BTUs |
| 350 to 400 | 9,000 BTUs |
| 400 to 450 | 10,000 BTUs |
| 450 to 550 | 12,000 BTUs |
| 550 to 700 | 14,000 BTUs |
| 700 to 1,000 | 18,000 BTUs |
| 1,000 to 1,200 | 21,000 BTUs |
Keep in mind that these are just starting points. Adjust based on the factors we have discussed, like insulation and window types. If you overestimate what you need, you might face high energy bills. If you underestimate, your mini-split won’t be as efficient.
If you’re still wondering, “What size mini split do I need?” for a multi-zone system, simply add the BTU requirements for each room individually. We do, however, recommend asking the professionals before deciding on a central air conditioning system.
No More Split Decisions on Mini-Split Sizes
As you can see, getting that “just right” feeling in your home is as easy as taking measurements, understanding what makes your home unique, and calculating what BTU is for you. If you’re after a more accurate answer to the question “What size mini split do I need?”, contact Confident Comfort and get a free quote. Our experts know how to calculate your system needs down to the last BTU, ensuring you enjoy comfortable temperatures without all the guesswork.