Jalousie Windows

Jalousie windows are one of the most effective windows for providing natural ventilation. In warm climates, having ample natural ventilation creates a much cooler house.

In some tropical and subtropical regions, jalousies are prevalent. Australia and some parts of Southeast Asia still use them often.

However, in several regions, jalousie windows are thought of as being old fashion and outdated. Some people refuse to use them anywhere in their new home. This approach is unfortunate since jalousie windows often outperform most other popular window types in tropical countries. 

Though not as popular today, adding jalousie windows to your home is a great way to cool your home naturally.

There has also been a lot of development in the design, performance and durability of jalousie windows over the past few decades.

The jalousies of today are not like those 40 years ago.

What Is A Jalousie Window?

A jalousie is a window that consists of horizontal slats or blades parallel to each other. These blades are in a frame that typically allows them to open and close together. The blades come in different materials, including glass, wood and metal.

Why Are They Called Jalousie Windows?

Jalousie is a French word. It means jealousy.

However, it is not clear how the name relates to the windows. Some believe it comes from the slats of the louvre windows screen inside from the eyes of jealous people outside.

Differences Between Jalousies And Louvre Windows

Louvre is generally another name for a jalousie window. Depending on the region determines which name is more popular. 

Countries such as Australia, the United Kingdom, India, the Philippines and Singapore use louvre. In the United States of America, they spell it as louver.

In addition, while jalousies always tend to be operable (the slats open and close), louvres can refer to fixed and operable options.

Why Did Jalousie Go Out Of Style?

In the early to mid-1900s, jalousie windows were trendy. They were most prevalent in hot, humid climates because they promoted good natural ventilation and light. Many traditional homes in tropical regions had jalousie or louvre windows. 

However, jalousies are not as popular today because of performance issues. 

With the increased use of air-conditioning, traditional jalousies became less favourable because of air leakage.

Also, traditional glass jalousies were not very secure. It was easy to remove the glass panels. 

Soon, some regions began to replace jalousies with sash and other types of windows. Today, most people consider jalousie windows to be outdated an old fashion. 

Do They Still Make Jalousie Windows?

Yes. Some companies still make jalousie and louvre windows. They are still prevalent in some parts of the world. In Australia, several traditional and modern homes use louvre windows. 

I sometimes play a game where I try to guess which country a house is in. Homes in northern Australia usually have louvres which make them easy to identify. 

Photo: Mansyur Hasan | Trapezioma | Andyrahman Architect

However, some regions in South and Southeast Asia still use jalousies.

Innovations In Modern Jalousie Windows

As mentioned, traditional jalousies had some significant flaws with their design and function. For modern home applications, these deficiencies made louvre windows unpopular.

If you search on the internet, you will find several articles saying why jalousie louvre windows are not good. These sites mainly reference air leakage safety and security issues.

However, these articles refer to old, traditional jalousies.

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Newer jalousie windows have made significant progress in functionality and performance.

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Modern louvre and jalousie window designs have several improvements. Hence, making them vastly superior to the old traditional jalousies of the past. They are once again an excellent option for contemporary homes.

Improvements and innovations to modern jalousies and louvre windows include:

• Enhanced safety and security features.
• Better water and air tightness.
• Impact resistance in hurricanes and storms.
• Glazing options for low UV transmission rates.
• Increased sound insulation ratings.
• Automated and motorised open and close functionality.

Types of Jalousie Window And Materials

The blades of jalousie and louvre windows come in different materials. These include glass, wood, metal, acrylic and PVC.

Opaque louvre blade options like wood and metal were once popular. 

When I was younger, I would sometimes see wooden jalousies in old traditional houses. These wooden jalousies were of skilful craftsmanship. The blades and frame were both made of timber. You could open and close them, and a metal pin or nail could lock them in position.

I worked on a project some years ago that recreated this type of traditional wood jalousie. The wooden slats fit into vertical wood strips. One of the strips are free to slide within a frame which allows the window to open and close. It is a simple but effective design and I believe still has a place in modern design.

Subsequently, more modern timber louvres blades were in a metal frame system.

Metal louvres were also typical, primarily in buildings like schools. However, some homes in regions with a lot of tropical storms and hurricanes often use metal louvres. These louvres were more durable and would have excellent resistance to impact from flying debris.

Eventually, glass louvre blades in metal frames became one of the most popular materials. The glass could be clear, frosted or sometimes even have a texture. They could let in more light and offer transparency even when closed.

Jalousie Windows and Air Conditioning

One of the main reasons that jalousie windows stopped being popular was their inefficiency in air conditioning.

Traditional jealousies were not very airtight. The spaces between the slats and around the frame would leak a lot of air. 

Therefore, as mechanical ventilation became more widespread, jalousies and louvre windows lost popularity. They were inefficient, and their air leakage caused homeowners to waste energy.

Photo: Veronica Sagredo | Gavin Steet House | People Oriented Design

However, some modern manufacturers are creating more airtight jalousie windows. Hence they prevent less air leakage in rooms with air conditioning.

Manufacturers such as Safetyline Jalousie have their louvres blades framed on three sides. In addition, the opening side presses against a rubber seal. This arrangement creates a tight seal that keeps air from penetrating. 

Pros of Jalousie Windows

Jalousie louvre windows have many benefits. In warm, tropical climates, they are significantly more advantageous. The reason is that they provide natural ways of lighting and cooling your house or building. Whether its cross ventilation at lower levels or stack ventilation for upper level windows or clerestories.

Photo: Cathy Schusler | Ridge House | Bones Studio

Although jalousie louvres are not as popular in some regions, they offer many benefits.   

Here are some of the pros of jalousie louvre windows provide.

• They permit almost 100% of their opening for natural ventilation.
• When partially closed, breezes can flow through while keeping out light rainfall.
• Opaque louvre blades like wood or metal can help shade from direct sunlight entering your room.
• Louvres with opaque or translucent blades can provide privacy while open.
• They have more flexible size options.

If you understand the benefits of jalousie louvre windows better, you may see why they are advantageous. These advantages make them ideal windows for your modern tropical home project.

Cons of Jalousie Windows

Most of the disadvantages of jalousie windows tend to relate to old, traditional systems. These cons include issues with security, air leakage and durability.

However, modern manufacturers have much better products where most of the disadvantages no longer exist.

Another con of jalousies is that there are not many manufacturers making quality products. If you want to benefit from the current selections in jalousie windows, there are only a few options.

Conclusion

Jalousie windows have had a complex history. Their inefficiencies and poor quality made them lose their popularity.

However, the benefits of jalousies in warm climates still make them an excellent window option for your tropical architectural home. In addition, the improvement in modern systems makes them more comparable to other windows.

Their ability to maximise natural ventilation makes them a great asset in a home for tropical climates.

Featured image photographer: Peter Eve
Project: Inside Out House
Architect: Sabi Design