What Size Of Air Conditioner Do I Need in Texas?
Burnside Air Conditioning, Heating & Plumbing

Selecting the right type of air conditioner system for your home might seem like a complicated task. However, with our team’s help, it doesn’t have to be. Each home is different, and each homeowner needs to consider their own, specific cooling and heating requirements.Furthermore, homeowners should consider each unit’s cost, required maintenance, and required labor. Different sizes of air conditioners come with different performance qualities, efficiencies, and total costs of operation and installation. It’s a lot to think about! However, by understanding and weighing these many factors, you should be able to narrow down your choices exponentially.
Why Size Matters
As a homeowner, you have an obligation to care and comfort of everyone living in your house. Part of that responsibility means selecting an effective air conditioning unit. The first step is setting up the right sized cooling system.In some cases, sizing an air conditioning system may require a consultation with a professional. They can examine the various factors that affect your home’s cooling, like the size of the house, the layout of each room, and the current type of system.A professional will be able to consider the following carefully:
- The total space of your home (not just the square footage).
- The number of sun-exposed exterior walls.
- The number, age, and current condition of all windows in the home.
- The amount of sunshine your home experiences throughout the day.
- The age of your home.
- The existing ventilation and ductwork systems.
Installing a home cooling system is not simply a matter of dropping off the unit and powering it on for the day. The system must fit the home. An air conditioner’s size matters because only the right size air conditioner will run a full cycle that will keep your home cool for long periods of time.An incorrectly sized air conditioner might only partially cool your home — on the other hand, it could expend more energy than necessary. You might experience warm spots, increased monthly utility bills, or a home that cools at a snail’s pace.
Breaking Down Air Conditioning Systems
Many homeowners believe that a large air conditioner will provide more efficient cooling. However, an oversized unit is less effective overall – it will waste energy. An air conditioner should both remove excess heat from the house and cool the remaining air. If the unit is too big, it will cool the room off quickly, before it can remove all the humidity from the air. Your home will feel damp and somewhat clammy.On the other hand, a properly sized air conditioner will completely remove the humidity from the air and fully cool the whole home. Sizing is critical! This brings back the central question: how do you properly size an air conditioner?Thankfully, Energy Star, the world’s leader in energy efficiency, created a simple guide specifically to address this question. Below, you can see home or room sizes (in square footage) matched with air conditioner capacities (in BTUs — British Thermal Units, a unit of measurement for energy).
- 100 to 150 square feet – 5,000 BTUs
- 450 to 550 square feet – 12,000 BTUs
- 1,000 to 1,200 square feet – 21,000 BTUs
- 2,000 to 2,500 square feet – 34,000 BTUs
Their website goes into further detail, but this guide can get you started. You might be surprised at the size of most homes. On average, the living room of an apartment or small home is around 330 square feet, which means that it requires an air conditioning unit with an 8,000 BTU capacity.However, you should consider a few other factors in addition to the room’s square footage. In some instances, you will need to think about environmental issues. For example, a lot of natural sunshine in a room may increase the capacity requirement. Likewise, for a dim room, you can decrease the capacity by 10 percent. If many people frequent a room, add 600 BTUs per person.
Average Room Sizes
In the vast majority of modern households, people spend most of their time in the bedrooms, playroom, and living room. In a small bedroom or office, you’ll want an air conditioner designed for comfort and quiet. These rooms are typically 100 to 300 square feet in size.On the other hand, a master bedroom or playroom measures around 250 to 400 square feet — these require a bigger and more efficient system. You’ll want to consider a mid-sized air conditioning unit. Finally, most living rooms are around 350 to 650 square feet. If the room has a large, open floor plan, you’ll want a bigger system.To determine the size of a whole-home air conditioning system, you’ll want to consider each room, its uses, and the floor plan of the home. Alternatively, have a professional contractor handle the task. They know exactly what to look for, and can get the job done quickly and easily.
Energy Efficiency
When sizing an air conditioning unit, you should also consider the system’s energy efficiency levels. Every air conditioner on the market today is labeled with an EER — an Energy Efficiency Rating. Units with a high rating offer fewer emissions and, as a result, have lower monthly operating costs. EERs range from 8 to 11.5. Once again, the higher the number, the more efficient the system.Furthermore, each system should have a yellow Energy Guide label with further information. Shop around and examine this information carefully before making a final purchase.
Additional Tips
First of all, if you intend to have a professional technician survey your home and help you determine the correct size for your air conditioning system, make sure that they perform all the accurate calculations. No specialist, no matter how experienced, can simply look at your house and determine the exact size best suited for your home.Sure, an experienced contractor could ask a few questions and offer an estimate — possibly even a highly accurate estimate. However, you should be wary of any contractor who simply looks at your home and offers a prompt recommendation without much consideration. They have to do more work to tell you what size unit you should buy.Secondly, consider replacing the ductwork of your home if they show signs of wear and tear. Improper ductwork essentially clogs the air conditioning system. A hotter room may require multiple ducts and registers. If you don’t have these, you’re not fully utilizing the power or efficiency of your new air conditioning system.Finally, remember to perform a little research on your own. This is your home, and your comfort is on the line. Once you have the size of an air conditioner in mind, consider examining the top brands, maintenance plans, and qualified installation professionals. Selecting the right size air conditioner is only the first step in the battle for a cool, comfortable home.Throughout this process, think of the long-term. While a window-mounted air conditioning system is ideal for a small apartment or college dorm room, these systems are not very efficient over time. You could save money and time by investing in a wall-mounted unit with proper ductwork. You will make a high initial investment, but you’ll recoup costs over the next few months and certainly the next couple of years.
Final Thoughts
There are certainly a lot of variables to consider when selecting and properly sizing an air conditioning system. The help and experience that a professional can offer could make all the difference. Whether you ask for help or go it on your own, be sure to consider variables such as the insulation, number of windows, and construction type. These factors will significantly affect the required number of BTUs per square foot for both cooling and heating systems.
Contact Us
If you’d like to schedule a consultation or have a professional contractor survey your home, contact Burnside Air Conditioning, Heating & Indoor Air Quality by calling (972) 562-7789 We’ll help you select the right-sized air conditioning unit for your home’s needs!
Need Help?
Contact us today to discuss your needs. Our team is ready to help.
About the Author
Burnside Air Conditioning, Heating & Plumbing
More Articles
View All PostsRelated Articles

How Long Should a Typical Furnace Repair Service Take?
Waking up to a freezing house is stressful enough without guessing when your heat will return. We break down the exact timeline between diagnosing the issue and fixing your furnace.
Read Article
The Impact of Clogged Burners on Furnace Efficiency and Safety
Rust and debris can silently block your heating system's gas flow, creating hidden hazards. Learn to spot the signs of incomplete combustion early to protect your home.
Read Article
Why Tankless Water Heaters Need Specific Freeze Protection in Texas
Exterior-mounted tankless units are highly vulnerable to sudden Texas cold snaps. Understand the risks to your isolation valves and why professional winterization is the safest choice for your home.
Read Article
Navigating Gas Line Safety Inspections for Furnace Replacements in Prosper, TX
Replacing a failing heating system shouldn't mean drowning in municipal red tape. Discover what to expect during your mandatory town safety inspection.
Read Article
Programmable Thermostat Upgrades: Wi-Fi Connected vs. Local Control Only
Deciding between a high-tech smart thermostat and a reliable standard model can be confusing. We break down the pros and cons so you can confidently choose the right upgrade.
Read Article
Diagnosing a Clicking Sound Before the Furnace Ignites
When you turn on the heat during the first cold snap, rapid clicking from the HVAC closet can be startling. Find out if it's a normal spark igniter or a sign you need repairs.
Read Article
How Short Cycling Damages Your Furnace Blower Over Time
If your heating system constantly shuts down after just a few minutes, it's causing invisible mechanical wear. We break down why these short run cycles threaten your blower motor.
Read Article
Heating Solutions for Historic Homes in Downtown McKinney, TX
Upgrading the heat in your century-old property shouldn't mean tearing down original plaster. Discover non-invasive HVAC options that deliver modern comfort while preserving architectural charm.
Read Article
Tackling October Indoor Air Quality Challenges as Windows Stay Closed
When you shut your windows for the season, indoor VOCs and odors get trapped inside. Transitioning to active HVAC air management is the key to keeping your home fresh.
Read Article
Humidifier Integration: Bypass vs. Fan-Powered Systems for Dry Texas Winters
When Texas winters dry out your home, choosing between a bypass and a fan-powered humidifier is a critical decision. See how your specific HVAC layout dictates the right system.
Read Article
Does My Heat Pump Need a Defrost Cycle Check Before Winter?
Your heat pump has a hidden vulnerability when temperatures plummet. A proactive defrost cycle check in October is the best way to avoid a total freeze-up in January.
Read Article
How We Detect Microscopic Gas Leaks Around Your Furnace Manifold
Winter cold snaps put immense stress on heating systems, causing dangerous pinhole fissures. See why relying on your nose isn't enough and how our tools keep your family safe.
Read ArticleReady to Get Started?
Whether you need a repair, maintenance, or a new installation, our expert team is here to help.
