Corner windows – advantages and disadvantages of glass corners

Few solutions in the world of windows and doors generate as much excitement as corner windows. This is an exceptionally striking option that can instantly become a home’s standout feature and a favorite among its residents. Who can benefit from this solution? Is it a good idea? How should you go about installing corner windows? Let’s find out.

• Corner windows stand out with their unmatched design, excellent technical specifications, and beautiful views from the interior, though these advantages come at a higher price.
• Large corner windows, in particular, should ideally be included in the design from the construction phase to ensure that the building structure meets all necessary requirements.
• Corner windows with a mullion consist of two fully functional windows positioned at different angles. In contrast, step glass windows feature fixed glazing arranged at a right angle, allowing for the omission of a mullion.
• If the technical capabilities of the building allow, corner windows can be a striking and prestigious addition that enhances aesthetics and creates comfortable interiors.
• When replacing windows, it’s also worth considering updating the entry doors. Wondering how to change them to new ones? You can find out in our step-by-step guide.

• What are corner windows?
• Advantages of corner windows
• Disadvantages of corner windows
• Two types of corner windows
• Corner windows with a post
• Corner windows with a step
• Are corner windows a good option for me?
• New construction
• Replacing old windows

What are corner windows?

Corner windows are a solution that is both innovative and, in many ways, quite obvious. A house with numerous large windows is a much more attractive place to live than a building that lacks access to natural light and is closed off from its surroundings. We install windows wherever we can, so why not in the corners of buildings?

Why haven’t we done this before? The answer lies in technology. The construction of corner windows is relatively complex, but there’s no need to be intimidated. For residents, the benefits and daily enjoyment far outweigh the challenges. Developing such windows posed a challenge for engineers, and there are specific requirements for the building that we will discuss further in the text.

Advantages of corner windows

The advantages of corner windows are evident in three main areas:

• building aesthetics
• comfort for residents
• energy efficiency

The popularity of this solution is rapidly increasing, as it’s hard to overlook a building where the architect has fully utilized corner glazing. These windows not only look ultra-modern but can also surprisingly complement rustic styles, especially when wooden frames are chosen.

Comfort for Residents is enhanced in several ways:

• more light: Sunlight enters the room from at least two directions.
• increased space: Additional glazing creates an optical illusion of a larger space.
• better views: Corner windows provide unobstructed views of the surroundings.
• opening up small rooms: In smaller kitchens, panoramic corner windows can help eliminate the feeling of confinement.

Energy efficiency is closely linked to comfort, as the excellent thermal performance of corner windows contributes to an optimal indoor temperature throughout the year. Modern profiles and double-glazed units significantly reduce heat loss, while large glass surfaces allow for greater solar gain in winter, maximizing the benefit of sunlight.

Disadvantages of corner windows

Every rose has its thorns, and corner windows are no exception. However, those expecting a long list of serious challenges can lower their guard. The real challenges boil down to two main issues:

• cost
• technical requirements for buildings.

The cost of corner windows is not exorbitant, but it is higher than the average price of windows used in modern construction, primarily due to the demands on corner structures. Large corner windows must provide adequate insulation, possess sufficient structural integrity, and effectively resist wind and water pressure. The characteristics of corner windows necessitate the use of high-quality systems. Whether they are plastic, aluminum, or wooden corner windows is a matter of personal preference.

In practice, it’s crucial to note that the installation of corner windows can only proceed if the building's structure allows for it. This is tied to additional requirements concerning the strength of the lintels. In the case of large corner windows, it may often be necessary to construct a reinforced concrete frame.

Meeting these requirements is usually not difficult for new builds, but replacing traditional windows with corner ones might not be worth the trouble.

It’s also worth mentioning window coverings. Enhancing the functionality of corner windows with blinds and shades is advisable, but not every system can work with them. Furthermore, proper preparation of the building for installing such additions is often necessary. These are quite complex issues that require prior planning, but a reliable guide through these matters is always the distributor-installer, who can recommend the right solutions.

Two types of corner windows

Before deciding to purchase corner windows, we need to familiarize ourselves with their two types:

• corner windows with a post
• corner windows with a step

The apparent difference between them is slight, but the functionality of corner windows of both types differs significantly.

Corner windows with a post

Corner windows with a post are, at least in terms of the technologies used, nothing extraordinary. They are simply two standard windows connected together, except that they are usually joined at a right angle rather than 180 degrees.

The post, which is a standard window profile, provides additional stability to the structure, making the installation of corner windows similar to that of regular windows, just in an unusual location.

If they have everything, why do we need another type of corner window? It is due to the presence of the post, which prevents achieving a uniform glazing effect—something that many investors desire.

Corner windows with a step

Corner windows with a step offer the greatest prestige and the best aesthetic effects for the interior. The step connection involves precisely joining the edges of the glass, which are ground at a specific angle, and bonding them with a dedicated structural adhesive. The connection is then secured in various ways, such as with silicone or masking tape. This type of connection is visible but does not draw much attention.

One could say that step windows are a more modern type of corner window, but in reality, they represent a different set of possibilities. We achieve almost all glass in the corner, but potential investors must know that this comes with certain compromises:

• The windows are fixed: This type of window is installed permanently and does not open.
• Higher price: Choosing a step instead of a post increases the investment cost by several dozen percent.
• One connection angle: Corner windows with a step can only be joined at a 90° angle.
• Higher requirements for the building: The lack of a reinforcing post raises the requirements regarding the static parameters of the wall.

Eliminating the post in a corner window significantly improves its aesthetics, but this comes at the cost of functionality. A window without a post cannot be opened for ventilation or easily cleaned from the outside. However, its appearance will be enhanced, leading to a better impression in the interior.

Are corner windows a good option for me?

New construction

If you are in the process of building a house, installing corner windows is an excellent idea, especially if the building's location raises concerns about proper interior lighting. Such glazing is a great ally when you want to maximize the use of natural sunlight.

It is important that large corner windows are included in the design rather than added at the last minute. This way, you can avoid costly changes to already constructed parts of the house.

You definitely need to consider the costs, as corner windows may require a higher financial investment. However, compared to other top solutions used especially in passive construction, the price is not prohibitive.

Replacing old windows

More modern corner windows can typically be installed in buildings that previously only had traditional windows. However, as mentioned earlier, it is necessary to check the building's structure for strength, as these windows bear loads differently than bricks or concrete blocks.

If the goal of replacing windows is to improve the building's energy efficiency, the type of windows should not be a hindrance. Modern window and door systems feature very good thermal parameters—often even better than the profiles themselves. You can also be assured of their resistance to wind and water pressure.

In renovation projects, it is often advisable to forgo windows with a step, although many investors may not even be aware of this and choose corner windows with a post right away.