What is a Curtain Wall?

These days, there are a whole host of building and architectural techniques when it comes to constructing a new building. 

Advances in technology and materials mean that so many different design options are available during the construction process, and one of the most popular options is curtain walls.

If you’re interested in architecture, it’s likely you’ve come across this style before. But if you’re new to the concept or simply want to learn more about it, we’ve put together this handy blog to help.

We’ll answer the question of ‘what is curtain walling’ as well as provide you with all the information to ensure you fully understand the process.

What Is A Curtain Wall?

If you’re wondering ‘what is a curtain wall?’, we’re here to help.

In summary, a curtain wall is a non-structural cladding system for external walls on buildings. Most common on skyscrapers and multi-storey buildings, they keep the interior and exterior of buildings separate- keeping the weather out and people in.

Unlike most orthodox building methods, curtain walls do not support any structural elements whatsoever. In fact, they only support their own weight and any weight that is imposed on them (such as wind). This is very different from most walls that are built. 

Due to this, curtain walls are typically made from lightweight materials. Primarily, they’re made from an aluminium frame that comes with opaque or infilled glazing.   

Curtain walls can also be customised bespoke to the design requirements of the building they’re set to feature on, and the facade is extremely aesthetically pleasing.   

What Is A Stick-built Curtain Wall?

Most curtain walls are unitised- meaning they’re created and glazed in a factory before being transported to the site where they’re being used.

However, this is not always the most appropriate option depending on the specifics of a project. 

In situations where a unitised curtain wall is unsuitable, a stick-built curtain wall will likely be used. 

A stick-built curtain wall type is constructed differently from its unitised counterpart. Instead of being built in one place and transported to its destination, the components of a stick-built curtain wall are assembled piece by piece on-site. 

The frame and glazing elements are put together in a systematic manner, almost like a jigsaw puzzle.

While this method is more labour-intensive, it can be more cost-effective and provide more thermal movement.        

The History of Curtain Walls 

Curtain walls are nothing new. 

In fact, they began emerging as far back as the 1800s but really started to gain prominence in the 1930s as a result of aluminium becoming more widely available in the construction industry. 

Since then, curtain walls have been used in construction projects all over the world with some of the most famous architectural landmarks featuring them. 

They’re also closely associated with the modernist style that started to become popular in the middle of the 20th century, with the use of glass and repetition of units both being very common elements in curtain walling. 

What Are The Features of Curtain Walls?

Now we have a thorough understanding of what curtain walls are, let’s take a closer look at some of their main features.  

• Non-structural: As already mentioned, a curtain wall does not support the building’s load. Instead, it transfers its weight to the main structure of the building, including its columns, floors and foundations.
• Glass panels: Another common feature of a curtain wall is the use of glass panels. This type of glazing allows natural light to enter the building, giving its occupants a pleasant light source that can be beneficial if working in an office environment. 
• Aluminium frames: Since aluminium became a widespread building material, the popularity of curtain walls has soared. Curtain walls almost always come with this kind of panel in place, providing it with strength, durability and corrosion resistance. 
• Weatherproof: One of the main features of curtain walls is that they offer great protection from the elements. They are able to protect the interior of the building from rain, wind and temperature fluctuations.
• Thermal efficiency: Curtain walls often incorporate thermal breaks and insulated glazing- meaning energy efficiency is enhanced.    

What Are The Benefits of Curtain Walls?

Curtain walls provide buildings with a number of great advantages. 

Due to their lightweight nature, curtain walls are extremely affordable. This is a particular advantage if the building project is significantly large, as the affordability of the technique will not compound costs too much.

As well as this, because of the system’s weatherproofing ability, it can help a building become extremely energy efficient. Keeping adverse weather out will ensure a building does not incur higher costs of heating or cooling. 

Another advantage is that curtain walls are incredibly versatile. They can be installed on both small and large buildings, making them a hugely popular choice on a wide variety of projects.    

In addition to all of these functional benefits, curtain walls are also aesthetically pleasing. Their contemporary, modern appearance has seen them used on a whole host of large-scale projects around the world.    

Examples of Curtain Walls Around The World 

Curtain walls have become a popular design choice for some of the world’s most iconic landmarks and buildings. 

Just a few examples include:

• The Gherkin: London’s distinctively shaped office building was built in 2004 and includes a curtain wall of diamond-shaped glass panels.
• The Empire State Building: New York’s top tourist destination includes a great early example of a curtain wall on its facade. 
• Burj Khalifa: The tallest building in the world can be found in Dubai and features an impressive curtain wall system. The facade is made up of reflective glass panels which change appearance during the day depending on the amount of sunlight it receives. 
• The Louvre Pyramid: Paris’ Louvre Pyramid was completed in 1989, and features and iconic glass and metal structure that serves as the main entrance to the museum. It is a superb example of a curtain wall not on a skyscraper.
• Petronas Twin Towers: Completed in 1996, the Petronas Twin Towers in Malaysia’s capital Kuala Lumpur was previously the tallest building in the world. Their curtain walls consist of a combination of stainless steel and glass that give the towers a striking appearance.