Summers have a way of turning the outdoors into a relaxing and refreshing getaway. Sadly, you cannot say the same for indoors, especially for the attics. Attics are one of the most neglected areas of a house, and on hot summer days, they tend to burn like infernos. As a result, it becomes quite a challenge to cool your attic space.

The blaring sun can raise your attic temperature quite a bit in summers. Your best bet to maintain the perfect attic temperature is by installing an air conditioner. Choosing the best AC for your attic might be challenging and requires a lot of research. From things to consider when buying attic AC to choosing the right type, this guide will cover everything for you.

A small attic bedroom. Cielo Breez Plus is paired with mini-split to maintain ideal temperature.

Why Do You Need an Air Conditioner in the Attic?

Once just considered storage rooms, attics are now being transformed into valuable extra home space. Attic conversions started as a trendy remodeling project, but soon it became much more of a need. You can use the extra space as a home office, studio, guest room, home library, or anything that suits your needs.

One major problem that might be in your way is attic cooling, which is no easy job. Therefore, it is necessary to install an air conditioner in your attic.

An attic air conditioner helps you maintain a comfortable temperature in your attic.
In some closed-off attics, warm, moist air can gather in, and humidity levels go high. This can encourage mold growth. Since an air conditioner cools by removing water vapors from indoor air, it’ll help regulate the humidity levels in your attic.
The hot air in the attic transfers the warmth to the lower levels, especially if your attic isn’t properly ventilated and insulated. This affects the overall home temperature, putting a strain on your HVAC system and increasing your cooling costs.
An attic air conditioner elongates the life span of your roof by removing excess heat and moisture, as these two things can damage the structure of a roof.

Things to Consider When Buying an Attic AC Unit

An attic is the part of your house that is most exposed to temperature fluctuations. Moreover, the weird shape because of slanted roofs leaves very little space on the walls. That is why not every air conditioner would be fit to install in this space.

Here’s a list of factors you need to need to consider before getting an AC for your attic:

1. Attic Insulation

Before installing an AC in your attic, ensure there are no uninsulated spaces. If your attic is vented or uninsulated, there is no point in conditioning it because you’ll end up losing all the cooled air. The air conditioner in your attic already has to work harder than a regular room AC to cool the hot air. In such a case, a lack of insulation will further decrease the efficiency of your AC unit.

2. Heat Pump for Year-Round Comfort

It will help if you look for an air conditioner for the attic that can provide you with cooling as well as heating to stay comfortable in every season. This would eliminate the need to install two different units to heat/cool your attic.

3. Ease of Installation

Depending upon your attic space, choose an air conditioner that fits well and is easy to install. For example, installing a window air conditioner for an attic with small roof windows would be extremely difficult. Similarly, portable units won’t be suitable for small attics since they take up floor space.

Secondly, if you are on a budget, try to opt for a DIY-friendly AC to save installation costs.

4. Air Conditioner Sizing

It is of utmost importance that you buy an AC unit for the attic that is adequate in size. 20 British Thermal Units (BTUs) per square foot is sufficient for regular indoor space, but attics are different. These spaces trap heat from home and catch sunlight from above. That is how they end up extremely hot during summers.

So, for 400 sq feet, you’ll get 8,000 BTUs going by the formula. But you should choose an air conditioner with at least 10,000 BTUs for the attic. This will not cause your attic air conditioner to work harder than its capacity and maintain its cooling efficiency.

5. Energy Efficiency

While choosing your air conditioner for the attic, always check the EER rating of the AC unit. You should be looking for an air conditioner with a rating no less than 9. However, air conditioners with a 12+ EER rating are the real energy-saving giants.

6. Durability

Always keep the durability factor in view while buying an attic AC unit. For example, a good mini-split can last you for 15 to 20 years. On the other hand, a portable AC might be more convenient and less expensive but won’t last more than 7 to 10 years.

Types of AC Units Suitable for Attic

When it comes to installing an AC in the attic, there are various types of ACs you can choose from. If there is no ductwork in the attic, it is quite expensive to tear down walls to add ductwork in the attic and then connect it to your current HVAC system. Therefore, using a central air conditioner in the attic is not cost-effective. This narrows down your choice to buy a ductless attic air conditioner, which is much less hassle.

1. Mini-Split Air Conditioner

Mini-split AC units are your best choice as the attic air conditioner. These AC units are reliable and energy-efficient. Since their noisy part (compressor) is installed outside your space, they work quietly.

Although these attic AC units are a bit on the pricier side, their durability, quiet working, easy installation, and energy efficiency make them the best choice. They’re installed high on the wall, so you won’t encounter any space issues, but they won’t be suitable if the walls are short.

2. Window Air Conditioner

A window air conditioner is another choice, especially if you need a small air conditioner for the attic. They are the most inexpensive among all the other attic air conditioner options. Their energy efficiency is better than portable air conditioners but not as good as mini-splits.

However, you need to make sure you have a big enough window to install this type of AC. It gets close to impossible to install attic air conditioners on narrow or inclined windows.

3. Portable Air Conditioner

Portable air conditioners come with either one or two hoses that need to be vented out through a window or a wall. This is essential to effectively expel hot air and properly cool your attic. Attaching a hose can be tricky at times, depending on the size of your attic window and where it is located. However, if your window is easily accessible, then the entire process is made simple by a window kit that normally comes with portable AC units.

Portable units are popular because they can be moved around easily but also take up a good chunk of floor space. Another problem is that portable air conditioners for the attic are not as energy efficient as they should be. Secondly, they are much less durable than mini-splits and window units.

4. Through-the-Wall Air Conditioner

These air conditioners are called through-the-wall ACs because they are installed by drilling a large hole in the wall. In the case of attics, carving this hole can be quite challenging and should be done by professionals only. Moreover, they are big in size, so they do not look aesthetically pleasing.

Apart from the installation problem and aesthetics, there is not much you can complain about. These air conditioners are not as expensive as portable or mini-split AC. Another upside is that they are quite efficient, second only to mini-splits in that regard.

Attic Air Conditioner to Regulate HVAC System

Some people have their central air conditioning systems installed in attics. This is so because installing an HVAC system in the attic saves space. Secondly, installing air conditioning units in the attic is cheaper and more straightforward. You just have to install the unit and leave it there. You do not need to cover it and carry out all the finishing.

However, attics are the hottest part of a house and can get as hot as 100F to 150F, whereas the air inside ducts is cooled to a much lower temperature relatively. Since heat travels from an area of higher temperature to an area of lower temperature, this difference causes a lot of heat gain, especially when your ducts and attic aren’t properly insulated. In this case, you can use a ductless air conditioner in your attic to regulate its temperature. You can run your attic AC at a higher temperature which will be sufficient to keep the hot air away. This will not only increase the efficiency of your central air conditioning system but also bring down your cooling costs.

Use a Smart AC Controller With Your Attic Air Conditioner

You can increase the efficiency of your mini-split, portable or window AC unit in the attic by pairing it with a smart AC controller. Smart AC controllers allow you to control your air conditioner through an app on your phone. It helps you automate your attic climate and gives you vast control over different settings and modes from anywhere. The biggest perk is enjoying the perfect temperature and humidity levels while also saving money on bills.

You can set intelligent triggers as per your preferred temperature/humidity levels, and your air conditioner will automatically maintain it. A smart AC will allow you to set weekly schedules to condition the room exactly how you want to. If you use your attic as an office, you can set a schedule to turn your AC on for your work hours and then turn it off for the rest of the day.

Air in Your Attic?!?!