Thursday , July 18 2024

HVAC Systems: How Louvre Vents Improve Airflow and Light Control

Ventilation louvers are integral to ventilation and air conditioning systems in homes, businesses and industrial facilities. They create healthier living and work environments by bringing in fresh, cooled outdoor air and keeping moisture and debris out. And they also reduce harmful substances and humidity as part of a wider collection of HVAC and cooling system parts.

What are Ventilation Louvres?

A close-up image of a metal louvre vent installed on a rusted metal surface. The louvre vent is secured with four screws at the corners.


Ventilation louvres are building accessories with angled blades or slats, attached horizontally to wall, window or door frames. They resemble blinds or shutters, but function as natural ventilation, drawing in clean air. The parts function alongside other cooling equipment, such as fans to remove excess heat, moisture and polluted air from building interiors. Thus they have a vital role in occupant health and comfort. When placed in external walls, louvre vents protect against dust, rain, vermin and burglars. And they can reduce noise from noisy exteriors. Common household areas where they’re installed include kitchens, laundries and basements.

How They Work

Louvres are often used extensively to effectively manage airflow and air quality. This role is controlled by the number, size and design of the blades. Each blade has a unique configuration, leading to different types of louvre vents. By changing louvre sizes, angles and blade configurations, homeowners can control air volume into the premises, while limiting or obstructing outside water and debris. The simple design can be tailored to individual needs or varied rooms.

Where They’re Used

A close-up image of a metal louvre vent installed on a rusted metal surface. The louvre vent is secured with four screws at the corners.


With varied shapes, sizes, designs and finishes, vents can be found on exterior walls, doors and windows, at the end of ductwork in HVAC, and as architectural elements in interiors and exteriors. Choosing the right type is based on airflow needs and what you’re trying to achieve. All types are designed with airflow in mind, but some offer other benefits.

Different Types

You’ll find louvre vents in varying specifications, with design differences leading to varied uses. The aim is to balance outside protection and overall airflow. In this sense, there are three common types of louvre ventilation:

Stationary Straight Blade

Straight and flat blade profiles are found in areas where air performance is key. The blades have smooth surfaces to limit drag and allow other cooling components to easily draw air inside the premises. Blades are also designed with some level of water resistance. Here the number and angle of the blades are the main factors.

If air quantity is a priority choose louver vents with fewer blades and a larger unobstructed “free area” with more space between each blade. Stationary ventilation louvers are the most common type in homes and commercial and industrial buildings and can be tailored to meet specific applications with the use of numerous accessories, such as extensions and subframes to improve functionality.

Severe Weather Louvres

These are designed to efficiently remove or repel water. They have drain troughs on blade faces and drain channels in the jambs, whereas the sills are fitted with drain pans. The blades have chevron shapes with central curves allowing air to pass and slopes collecting moisture. Water is further limited with blade catches.

Adjustable Types

adjustable louvre vent on a wall


Choose adjustable louvres for the most versatility. These provide a good balance between weather protection and overall airflow. Blades can be adjusted from an open to a closed position depending on needs. Combination adjustable types are a more complex design, with straight blades louver vents on the outside and adjustable blades on the inside. The design does better at water and debris protection without limiting airflow.

How Louvres Benefit Your Project

Ventilation louvres bring a long list of benefits for any building. These include:

  • Improved airflow – get cleaner cooler air without accompanying debris, water or outside pollutants. The parts are effective, simple to produce and can be installed anywhere.
  • Increased water and soundproofing – effectively deal with water, wind, insects and vermin while still drawing cool air. Louver vents can additionally lower outside noise, leading to a quiet and more comfortable inside environment.
  • Security – metal variants with reinforced steel bars offer heightened protection against theft or tampering. Install these in businesses or areas requiring balanced airflow without risking outside interference.
  • Style – louvres add an understated architectural element. They come in varied sizes fitting existing doors, walls or windows, and in different configurations (single, double, triple) to suit varied aesthetic and project requirements.
  • Customisation – different mounting types (flanged, glaze-in, face-fixed), and the style considerations listed above means you can mix and match louvre vents for any building.
    The only possible downside is that they need some consideration in cleaning, especially types with angled blades.

Why Materials Matter?

Vents are made of metal, wood or glass. The highest strength, however, is offered by metal variants. Opt for aluminium if you need lightweight options, or high-grade stainless steel for outright strength and protection. Both metals can be treated and coated to achieve the desired look. For instance, black powder coatings add more rust resistance to stainless steel with the benefit of a matte aesthetic.