What Are Window Louvers?

Window louvers (also spelled “louvres”) are an architectural feature found on the windows of buildings since the Medieval Era. In the car world, they’re a series of slats placed either on the rear window or the side quarter windows of a vehicle. They’re intended to add style, reduce glare, and keep the car’s interior cool.

Popularized in the 1960s by cars like the 1965 Mustang GT350 and 1966 Lamborghini Miura, the trend continued well into the 80s. Though less common today, the aftermarket still offers hundreds of window louver options. Modern cars with retro styling, like the Ford Mustang and Dodge Challenger, are popular candidates to receive the louver treatment.

What Do Window Louvers Do?

Window louvers mostly add style to a car. However, they do offer some more tangible benefits. Originally, window louvers were designed to reduce the glare produced by highly-angled rear windscreens (such as the one found on the classic Mustang). They also help keep the interior cooler by allowing less sunlight to pass through.

There are no aerodynamic or performance benefits provided by window louvers.

Are Window Louvers Illegal?

No, window louvers are not illegal in any U.S. jurisdiction or any other country. However, some drivers have reported being pulled over by police for having them. Be sure to know the law in your area, if applicable.

What Types of Window Louvers Are There?

There are two main types of window louvers: rear window louvers and side quarter window louvers.

Rear window louvers are a large, single piece that fits onto the back window of a vehicle. They offer a stylish, classic look. Moreover, they grant the practical benefit of protection from the sun.

They reduce rear visibility a bit, but you can see through them with only a slight reduction in viewing area. The thin nature of the slats ensures there aren’t any huge blind spots.

Side quarter window louvers are placed on the rear side windows of a vehicle. They’re often (but not always) installed in conjunction with rear window louvers. Sometimes, quarter window scoops are used instead. These are solid pieces that don’t allow any light through.

Quarter window louvers offer shade for rear passengers, but also impede their view due to the angle. Overall, the sun and heat reducing benefits are not as large as with rear window louvers.

Quarter window louvers are less expensive than rear window louvers, offering a more affordable way to make a big impact on style.

Which Cars Have Window Louvers?

There aren’t any cars that come with factory window louvers anymore, but they were popular in the 1960s on muscle cars and exotics. The Lamborghini Miura is instantly recognizable for its rear window louvers. The 1965 Mustang GT350 had iconic quarter window louvers, while the 1969 Mustang Mach 1 added rear louvers. Other cars, like the iconic Delorean DMC-12, maintained the trend through the 1980s.

Today, louvers are reserved for enthusiasts who want to go the extra mile for style. Purists will argue that they only belong on muscle cars and pony cars, but you’ll see them on everything from hatchbacks to pickup trucks. Still, the Mustang is the most common car to see them on, due to its history and retro style.

Sources: The History of Window Shutters, All About Shutters