Window Vs Through-the-Wall AC (Differences + Pros & Cons)

Through-the-wall and window-mounted AC units look pretty similar; however, both come with significant differences that you must consider before buying one.

Both air conditioners are designed to cool one room, unlike centrally air conditioning systems that serve the entire home.

Moreover, they differ in the way they’re designed, which has a massive effect on the installation process as well.

Want to know more about the types of window air conditioners and wall-mounted air conditioners? If so, read our head-to-head “window ac vs. wall ac” blog and determine which AC unit best meets your requirements.

Pros & Cons Of Window AC Units

A window air-conditioning unit works more or less similar to a wall air-conditioning system; however, it’s placed on a windowsill, unlike through-the-wall ACs. Meaning it goes through a window rather than on a wall.

In contrast, Window AC units are good options to go for if you’re looking for an easy, quick solution, which is relatively simple to install. Even the inexperienced can DIY install the unit in three easy steps.

First, ensure that you take the correct measurements. Second, place the unit and carefully bolt it down. Lastly, caulk to seal around your air conditioner.

In addition to that, window air conditioners are less permanent and more portable compared to thru-wall models. Hence they are perfect for people living in a rented property.

Pros and Cons of Window AC

What We Like
  • Relatively more popular than wall air conditioners, and therefore, easy to find
  • Window air conditioners have comparatively higher efficiency and low noise level.
  • Water drains quickly from the indoor unit to the external unit without the need for intervention.
  • It replaces the indoor hot air with cool incoming air
  • Even smaller window air conditioners can sufficiently cool down 100-250 sq ft space. On the other hand, larger AC units can cool rooms up to 600 sq. ft.
  • If the unit is properly installed, it can even cool the equivalent of two rooms.
  • Window AC units can either be installed in the wall indentations or windows.
Things We Don’t
  • When you install a window air conditioner, it blocks your window and the outside view.
  • Water dripping from the unit can end up in a place you don’t want it, such as on a metal roof, street, etc.
  • It requires greater time and effort if you want it to be installed in another location or room.
  • Remember, not every window in the house or office supports window air conditioners.
  • Its installation can turn tricky if there’s no exterior support. In addition, there is a chance that the unit may fall outside.

Pros & Cons Of Through-The-Wall AC Units

If you want a permanent solution, then a through-the-wall air conditioner is the right choice. It’s similar to the window air conditioner as it extracts air passing through coils and throws cool air back into your room where it’s installed.

The primary difference lies in the location of installation. Unlike window AC installation, through-the-wall AC units require an HVAC professional to do the job.

This is because through-the-wall units require a hole to be drilled in the wall for proper installation, and hiring a professional is the best way to get a clean indentation.

And since through the wall air conditioners are heavier than window units, they need a sheath to be placed as well.

Wall AC units have several advantages. For example, it can save space and does not block the view from the window.

What We Like
  • Perfect if you want an effective and permanent solution
  • They are more subtle and aesthetically pleasing than window air conditioners
  • You can easily replace a wall AC unit as most through the wall AC units use a similar standard size sleeve
  • Like window air conditioners, these units also have low noise levels
  • These AC units dehumidify the indoor air and provide higher breathability
  • Through-the-wall AC units can rapidly cool space while filtering the air to provide improved air quality
  • It allows you to use the remote and control:
  • Fan power
  • Temperature
  • Timer
  • Airflow direction
Things We Don’t
  • Compared to the window air conditioners, these units are costlier to install because you have to call an HVAC professional.
  • Trickier to set up in few places
  • If the air conditioner isn’t well-insulated, it will allow air to blow inside the house.
  • Compared to the window air conditioners, these units have a smaller coverage area.
Pros and Cons of Through the Wall AC

Window Mounted Vs Wall Mounted ACs (Key Differences Explained)

Here are the key differences between through the wall air conditioners and window air conditioners:

Power, Coverage Area, And Location

Window air conditioners have greater BTU ratings than through-the-wall air conditioners. This means they have more power and can cool bigger rooms quite easily.

Window AC units are readily available between 5000-36000 BTUs and through the wall air conditioners between 8000-25000 BTUs.

However, before buying an air conditioner, measure the BTUs of your room so that you purchase the right unit for your needs.

While the wall-mounted variants are placed on the wall, connected to the external unit through an indentation, the window-mounted ones sit inside a window opening.

Furthermore, window air conditioners will ruin your view of the outside because it takes up the entire opening. On the other hand, wall-mounted ACs find their corner in a room and fit in aesthetically.

Installation Difficulty

Both through the wall and window air conditioners display varying levels of installation difficulty, but one is more straightforward than the other.

It takes one person to install window-mounted ones, and they don’t even require you to drill a hole or cut the wall. It is also important to get the angle correct for the long-term functioning of the unit.

On the contrary, wall-mounted air conditioners need a little extra effort and commitment. These AC units require you to drill a hole for external connection and ventilation.

And as mentioned before, it is better to leave wall AC installation up to the HVAC professionals because any minor error can set you back additional money.

Furthermore, if you’re a tenant, chances are you won’t be permitted to set up a wall-mounted air conditioner in the house as it will be a permanent change and a violation of the lease.

Energy Efficiency (Running Costs)

On average, through-the-wall air conditioners are more energy-efficient than window-mounted air conditioners.

Though there are a few exceptions (such as these models) on low-end wall-mounted units and high-end window-mounted units, our assessment holds true.

Wattages for wattages, through the wall ACs, can cool a larger space than window ACs. This is primarily due to how the AC units are placed.

Since window air conditioners are installed in the windowsill, they are at a disadvantage; windows are arguably the most badly insulated portions of a home.

On the contrary, through-the-wall ACs have the advantage of being set up on a wall. They are a permanent solution and are often adequately weatherproofed. This way, they can retain the cool air within the room with little effort.

As a result, wall-mounted AC units are considered more efficient (per BTU or watt) than window-mounted AC units.

Design & Aesthetic Look

Although window-mounted air conditioners come in all sorts of designs, they are not seen as an attractive addition to your room.

Placing a big block-shaped device in the window is the least attractive thing to do. It blocks natural light coming into your room; hence, it takes more away from the space than it adds.

On the other hand, wall-mounted air conditioners can be installed on any outside wall that’s unnoticeable.

This way, you don’t have to lose the view of the outside. These AC units take up minimal room and can be put anywhere on the wall.

Cleaning & Maintenance

Cleaning and maintaining both window and wall-mounted ACs is a roughly similar process, and neither is too difficult.

The process is even more straightforward if you have a window-mounted air conditioner with slide-out chassis. All you need to do is slide out the AC unit and start cleaning.

On the other hand, cleaning your through-the-wall air conditioner is also simple. Just grab a vacuum, a soft brush, and start vacuuming any dirt you see in the unit.

After that, put a few drops of dish soap in water and start spraying in the unit while simultaneously wiping the surface.

For long-lasting and effective operations, it’s better to clean your air conditioners twice a year; however, the filters should be cleaned monthly.

Smart Tech Options

In terms of smart tech options, both through-the-wall air conditioners and window-mounted AC units include many similar features that make them convenient to use.

Here are a few smart tech features that these units have:

  • Digital controls for changing room temperature settings
  • Adjustable louvers for providing air to any specific area in the room
  • Remote control
  • Auto-restart (in case of power failure)
  • Washable air filters
  • Programmable timer


Through-the-wall air conditioners are costlier than window air conditioners. And although there are several reasons for this, the two main are:

  • Wall-mounted air conditioners have to withstand the weather throughout the year.
  • Wall-mounted air conditioning units include some placement costs as well

Moreover, since through-the-wall ACs are a permanent solution, you’ll find more advanced built-to-last versions of these than you would for window ACs.

Nevertheless, on average, the cost of a window-mounted unit is anywhere between $140 to $500. This is due to most models being smaller in size and BTU output. In contrast, the average price of a wall-mounted AC unit is anywhere between $250-$1000.


When it comes to the noise level, window-mounted AC units exude slightly higher noise than wall-mounted air conditioners.

This is because most of the sound from an AC unit emanates from fans that blow hot air outside and cool air inside.

Window-mounted AC units also have less insulation than wall-mounted ones. This means you can clearly hear the blowing fans both on the outside and inside as well.

In addition to that, window air conditioners also make an annoying rattling sound, which isn’t audible with a wall-mounted air conditioning system.

This does depend on the model though. We have tested a wide range of models and found the quietest ones here.

Differences of Window Mounted Vs Wall Mounted ACs

People Also Ask (FAQ)

Are wall and window air conditioners ever the same?

Though through-the-wall and window air conditioners function similarly, there are still some significant differences in the installing and venting.

For instance, a window air conditioner vent to the corners and go to the existing window, whereas through-the-wall AC units vent to the backside and out the wall through an indentation.

Can you use a through the wall air conditioner in a window?

No, you can’t! Air conditioning units meant to be set up in the window opening can’t be utilized interchangeably with air conditioners intended to be installed or built-in through the wall, primarily due to their different vent operations and installation processes.

Can you use a window air conditioner through the wall?

No, you can’t! The design and structure of average window air conditioners aren’t suitable for installing through the wall.

How much does it cost to install a through the wall air conditioner?

Although the average cost of installing a through-the-wall air conditioner varies and depends on the type of ACs, heating and cooling capacity, efficiency rating, special needs and preparation, and of course, the labor rates.

Still, the average cost to install a wall air conditioner is $730 if you do it with an HVAC professional. But if you are DIY-ing it, it will cost you around $540.

How long do the wall and window air conditioners last?

Although the lifespan of air conditioning systems varies depending on several different factors, if you ensure they are well-maintained and checked, they can easily last anywhere from 10-15 years.

In addition to that, if you make sure they have regular repairs and checkups – both small and big – many air conditioners can last even more than 15 years.


If you’re searching for an effective and efficient air conditioning system that doesn’t need a complete revamp, you should choose between a through-the-wall air conditioner and a window air conditioner!

Both have their pros and shortcomings, and you should choose the one that best fits into your home and lifestyle.

Josh Mitchell

Josh Mitchell

My name is Josh and I am obsessed with DIY and improving my family home. HVAC topics can be tricky for homeowners so I decided to share my knowledge on the subject. When I am not working on DIY projects, you can find me at the beach or my local coffee shop.