Adding Central Air to Your House: Can You Install AC in Your Home?

Older homes may have charming features you won’t find in newer construction—wainscoting and stained glass windows come to mind—but they also lack modern comforts such as central air conditioning. That doesn’t mean you’re destined to endure oppressive summer heat or install window AC units if you live in an older home. Fortunately, it’s possible to add central air conditioning to an older home, even if it lacks ductwork. But, before you invest in a new system, consider these tips for adding central air to a house.

1. Know if You Have Existing Ductwork in Your Home 

The biggest factor that determines how easy (or complicated) it will be to retrofit your home with central air conditioning is whether you have ductwork. Homes equipped with forced air furnaces for heat have ducts that spiderweb throughout the ceilings and floors to circulate that warm air. If you’re not sure what type of HVAC system your home has (or even what an HVAC system is), simply look for the telltale metal louvered vents (called registers) that indicate you have ducts. You’ll find them on the ceiling and on the floor near the walls.

2. Know What Type of AC Unit Is Best for Your Needs

Some people turn on the AC as soon as the temp hits 70, while others hold out until they’re breaking a sweat while watching TV. It would go to follow, then, that not every type of home requires the same type of air conditioner. Before you go to have yours installed, know what meets your needs.

If you live in a sprawling Craftsman, roomy Victorian, or another type of large home, you’ll want a powerful unit that can distribute cool air evenly from top to bottom, so you should expect to pay more. 

3. Know if the AC Unit Is Energy-Efficient

While how much an air conditioning unit costs may be foremost in your mind, it’s also crucial to consider how much you’ll spend each month to operate it. Luckily, the Department of Energy (DOE) requires air conditioning unit manufacturers to rate the efficiency of their AC units and share that info with consumers. Central air conditioner and HVAC energy efficiency is indicated by its SEER (Seasonal Energy Efficiency Rating). The higher the SEER rating the more energy efficient the air conditioning is (and the less it will cost to run each month). You can find this rating on the AC unit’s bright yellow EnergyGuide tag. 

The savings can be significant. Trading out an old 9 SEER AC unit with a high-efficiency 14 SEER unit can cut operating costs by 35%, according to the DOE. 

Keep in mind that the price of air conditioning units with high SEER ratings is significantly higher. But while you’ll pay more upfront for an energy-efficient air conditioner, you’ll eventually make up that money and more in operating costs. You can also take advantage of rebates and tax credits offered by the federal government and utility companies for air conditioners with high-efficiency ratings.

4. What Size AC You Need

Take a Goldilocks approach when deciding what size AC unit you need and get one that’s just right. An air conditioning unit that’s too small for the space will run constantly to try and cool it, driving up your electric bill while shortening the lifespan of the air conditioner’s compressor and fan motor.

Likewise, bigger is certainly not always better when it comes to air conditioning units. When the AC unit is too large for the home, it produces too much cold air for the space, causing it to reach the setting on your thermostat before it finishes a cycle. This causes the air conditioner to turn off and on repeatedly in a process HVAC pros refer to as “short cycling.” Short cycling puts a strain on the air conditioner’s condenser and motor while running up your electric bill. 

While an HVAC service will tell you what size air conditioner you need for your home, it’s wise to understand how they make their determination, especially since the only remedy for the above problems is a costly replacement. Calculate the total square footage of the area you plan to cool, then multiply that number by 20. The resulting number is the size air conditioner you need in BTUs. For example, if you have 2,000 square feet of space to cool, you’ll need an air conditioner that produces about 40,000 BTUs. 

5. Know If the Existing Circuit Breaker Can Accommodate Your Needs

Buying new air conditioning and having it installed is all well and good, but before you start dream shopping and getting quotes, you should assess whether your home can handle the air conditioning in question.

In older homes, many circuit breakers just aren’t up to the task, which can lead to an unwelcome surprise: upgrading your circuit breaker at the average cost of between $750 and $2,000. Have an electrician near you assess your circuit breaker ASAP so you can confidently make your budgeting and installation choices.

6. Know the Cost to Install AC in Your House 

Before embarking on a big project like having air conditioning installed in your home, it’s always wise to go in with an expectation of how much you’ll be spending. While comfort is key to a happy home life, so is a comfortable number in the bank account.

If you plan on hiring an AC pro to install your air conditioning system, you should plan on spending $3,000 to $7,000 in total. That cost includes the price of the unit and the installation itself. HVAC system replacement costs between $5,000 and $12,500.

7. Get Several Quotes Before You Commit

It can be tempting to act quickly on a good deal once you think you’ve got one. While air conditioning installation can be costly, it can be a necessity depending on where you live. 

In other words, if it sounds too good to be true, it probably is. That’s why it’s essential to get at least three quotes from local air conditioner installers before signing any contracts.

Pros and Cons of Adding Central Air to Your Home

There are a few benefits and drawbacks to weigh when thinking about adding central air to your house.