Many homeowners consider installing mulled windows. These windows are certainly a good choice because they can enhance the beauty a home. They are good at bringing in sunlight and warmth.

However, there are many different types of windows on the market. There are even more window companies to choose from. This makes choosing the right windows for your space a difficult task. This is why we are here to help you.

In this information guide, we will cover just one type of window; mulled windows. We will explore how they will make your home look magnificent. However, we will also cover the drawbacks these windows bring as well.

If you are on the fence about whether you should choose mulled window, then read this article. Lets dive straight into the advantages and disadvantages.

What are Mulled Windows?

Mulled Windows From inside a house
Mulled Windows From inside a house

Mulling windows is the process of joining two windows together. So, mulled windows are two combined windows that are installed on a flat surface.

These windows are connected by the frames. Mostly, mulled windows contain windows of the same shape and type. But, you can combine windows of different types and heights as well.

Commonly, these windows can be joined together from top to bottom or side by side. However, you can also combine them in unique ways too.

The “mulled” word comes from the structural component known as a “mullion“. This component is used to combine two windows.

It is a dividing bar that is used to make multi-window configurations. It acts as a structural component. It is also known as a mull bar, mull strip, or stacking bar.

Professionals can combine windows on-site when remodeling and constructing a home. Additionally, mulled windows have been installed in the factories too.

Just as there are different series of windows in a company, factories also manufacture different types of mulled windows. Some of the examples include: bay or bow mulled windows, awning mulled windows, double frame mulled windows, specialty shaped mulled windows, picture mulled windows, etc.


Mulled Windows From inside a house
Mulled Windows From inside a house

There are various advantages which are discussed below.

1. More Sunlight

Mulled windows means there will be more of a glass surface area on your walls. They cover a large portion of the wall, allowing an enormous amount of sunlight to come into the room.

The sunlight will make your room appear more spacious. If your room is cramped and small, you should consider mulled windows. It will make your room feel much bigger than it actually is.

2. Energy Efficient

Mulled windows can save you on energy bills too. They allow a large amount of sunlight to illuminate your room. So, you don’t need to use much artificial light in that room.

So, you should install mulled windows in areas where you need more light. This aspect will help you in saving your energy costs.

Moreover, you should combine Energy Star certificate windows. These windows will keep your house cool in the summer, and warm in the winter. This is because these windows create a tighter seal, improving insulation and reducing drafts.

So, energy-efficient mulled windows will save you on your monthly and yearly electricity bills.

3. Outdoor View

Mulled windows can give you an expansive view of the outside because of their enormous size.

You can enjoy the sunlight and the beauty of the outdoors by creating a cozy sitting area in your home. This is all because of the mulled window. This aspect has also been seen to improve mental health.

So, we suggest you install mulled windows in areas where you will have a magnificent view.

For example, you can have mulled windows in out looking your garden, patio, or pool area. This beautiful outdoor view will also enhance the interior beauty of your room.

4. Boost Home’s Value

Mulled windows give a unique charm to your home. They enhance the architectural interest of your home. They also give your house a more modern and expensive look. Therefore, they also boost the curb appeal of your home.

This means you can sell your house for a higher price over your neighbors who don’t have this home feature. Therefor, these windows can benefit you financially.

5. Customization Options

You can ask your manufacturer to combine any two windows of your choice to make a mulled window. This customization option can make your home unique.

Through this, you can have your favorite mulled windows in whatever shape you desire. It is great for individuals who opt for a completely custom home. This aspect also makes this window more unique and appealing.

6. Focal Point

Mulled windows can draw attention to the home’s exterior and interior. All eyes will be focused on the mulled windows because they give a clean, finished, and beautiful look to your home.

The customization aspect means that you can make your windows look extremely unique. So, if you want the window to be the focal point of the room, then you can achieve this feat with mulled windows.

7. Improved Aesthetics

These windows can provide a modern and sleek appearance to your house. You can use them to cover the gaps and dark areas in your home. So, it will enhance the aesthetic appeal of your space.

8. Improved Ventilation

You can have better ventilation options through mulled windows. They allow you to open multiple windows and frames at one time.

So, in those places where you desire improved ventilation, you should install mulled windows.

9. Noise Reduction

Mulled windows have added layers of seals and glass. They are thicker than other window types, so you can use them to reduce outside noise. It will keep the inside quieter and more comfortable.

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10. Structural Integrity

Mulled windows provide structural stability to your home and the wall where you install them. So, we recommend that you install them even if you live in an area prone to severe weather conditions.

These are the pros of mulled windows. Now, we are going to discuss a few disadvantages of them.


There are some limitations or disadvantages which you should consider before buying these windows.

1. Heavy

Windows that are mulled are heavier and bigger than single ones. So, they are difficult to ship.

If you are buying them from the factory, you need to be careful shipping them to your home. There are chances that the windows will crack during shipping.

Additionally, these heavy windows are difficult to install. There are increased chances that an accident will occur during the installation process. Moreover, you need to put a lot of time and effort into installing them.

2. Building Codes

In some areas, building codes for these windows are strict. This is because these windows are not suitable for certain structures and buildings.

A lot of companies also believe that the rating of these windows is lower than the other types of windows. So, we suggest you consult the building codes before installing windows that are mulled.

3. Cost

Beware! These windows are more costly than other window types. It can be out of your budget because of its price, installation, repair, and maintenance costs.

As you know two windows are present in this window, so the preparation time and materials involved will be more than the other window types. If you want to know the true breakdown with costs, we advise that you consult with a professional. Find A Pro in You Area Here!

4. Limited Configuration

You may already know that these windows take up more space than ordinary windows. So, if you don’t have much space, you have to compromise on the design of the window.

This window provides you with a variety of customization options. But, you may be limited because of space constraints, or the lack of availability from suitable manufacturers in your area.

A lot of manufacturers don’t work on mulled windows, so you may not get your desired style.

5. Maintenance

You should also keep this fact in mind that cleaning and maintaining this window is more time-consuming and difficult than other windows. This is because it has a large surface area and more panes. So, cleaning can be a frustrating task. However, you can use a Robot Window Cleaner. Check out or Robot Window Cleaner Here!

6. Repair and Replacement

Just like maintenance, repairing and replacing mulled windows is also time-consuming and costly. This is because you can’t afford for one part of a mulled window to get damaged.

You need to replace and repair the whole window. And, as you can guess, this replacement requires a lot of time and money.

So, this is all about the advantages and disadvantages of mulling windows. Now, we are going to discuss a few factors. You should consider these factors before buying or combining your windows.

Factors to Consider Before Mulling Windows

There are various factors you need to keep in mind before installing these windows.

  1. You need to know that all windows can’t be mulled. Yes! You need to consider the material of the glass and the size of the window. They will determine whether you should join windows or not. If the mulled window becomes heavier, it can cause structural damage to your house. So, be considerate.
  2. There are chances that these windows will not be included in your manufacturer’s warranty. So, we suggest you check the warranty on the manufacturer’s website. Because losing a warranty can be a hard pill to swallow.
  3. You should never forget to check your local building codes before making any construction decisions. So, do remember to ask your constructor to consult the building codes before installing mulled windows.
  4. These windows have the capability to improve or decrease ventilation. It depends on their configuration. So, you should make sure that a large part of your windows can be opened. It will enhance the ventilation.

For any repairs, installations, builds, or questions; We recommend you to hire a professional. Find A Pro Near You Here!