We know louver selection can be difficult. In this article, we picked out four louvers, one from each category, to help meet your airflow requirements. Subscribe to MCDLG Newsstand for this and more.
Louver selection isn’t easy. One category can have up to twenty louvers and half of them will meet your project’s requirements. How do you choose? In this article, we will present louvers from four categories and explain why they are the best fit for a specific requirement.
You don’t have to choose our pick. Use each louver as an example of what to look for when meeting airflow requirements.
EA-662-VSL by Arrow United Industries
Standard louvers will typically account for rain in still or light wind conditions. The EA-662-VSL is built by Arrow United Industries for resisting wind driven rain. This louver is equipped with vertically oriented chevron blades. Chevron blades are an excellent balance between protection and performance. The curve of each blade can stop incoming water with minimal effect on air flow intake. That means you get excellent protection without compromising air stream.
With vertical blades, the EA-662-VSL can quickly drain water from its blades. This is known as gravity drainage, because the water falls to the louver’s sill. The rainfall can’t collect in the louver’s blade catches or drain channels. There is no need to worry about overflowing or backsplash, especially when the louver has a drain pan installed.
The EA-662-VSL is AMCA rated for Air Performance, Water Penetration, and Wind Driven Rain. The beginning point of water penetration on this louver is over the test maximum of 1250 feet per minute. For wind driven rain, this louver has a Class A rating at 100% efficiency for both phases. In other words, it fully rejected all rainfall during each test phase. Read this article for a complete explanation of wind driven rain testing.
Severe weather louvers keep rain out of your building. Look for louvers with an AMCA Ratings Seal for Wind Driven Rain. Then, check the louver’s submittal for the test data. Louvers with Class A reject 99% or more of incoming rainfall. Choose the louvers that meet your airflow requirements and protect the opening from water damage.
AS7D99CH by Airline Louvers
If you are building in a coastal region, then you will probably have hurricane requirements. These codes and standards ensure that your building is resilient to high winds and heavy rainfall. As part of these requirements, you will hurricane louvers in your ventilation opening.
Hurricane louvers are designed to resist two aspects of a hurricane: high velocity wind driven rain and impacts from windborne debris. As the name implies, high velocity wind driven rain is rainfall driven by high winds:
This is the maximum wind speed of a category two hurricane, according to the Saffir-Simpson Hurricane Wind Scale.
Hurricane louvers are tested under AMCA Standards 540 and 550, each focusing on one of aspect of hurricane louver protection. AMCA Standard 540 tests a louver’s ability to withstand windborne missiles and AMCA Standard 550 tests its ability to reject rainfall in hurricane conditions. The AS7D99CH by Airline Louvers is listed for both.
The AS7D99CH is a combination stationary louver consisting of two sets of chevrons blades. The forward blades are horizontal, keeping the horizontal profile of a traditional louver. These blades are drainable, connected with drain channels in the jambs that lead to the louver’s sill.
The back-end blades provide an additional layer of protection from wind driven rain. These blades are vertical, like in the EA-662-VSL, providing gravity drainage directly to the louver’s sill. The AS7D99CH also comes with a drain pan as a standard feature.
Hurricane louvers provide top-tier protection during the worst weather events. If your project is on a coastline, then you should consider adding hurricane louvers to your ventilation points. Check for AMCA listing labels for 540 and 550. These labels signify that the louver has passed the test for each standard.
A4SHP by Air Balance
It may seem like the best option will always be hurricane louvers, but that isn’t the case. You should pick the louver that meets your project’s requirements. If you don’t have a requirement for hurricane or severe weather, then you should look for louvers that meet your airflow needs.
We mention this a lot on the Newsstand. If you have too much protection, then you can lose out on air performance. This is why it’s important to choose the louvers that best fit your project. For mild weather, consider using non-drainable louvers to maximize airflow efficiency.
The A4SHP is a high-performance stationary blade louver by Air Balance. This louver uses straight blade with no drainable trough. The blades are angled at 42 degrees to deflect incoming rainfall. This blade angle deflects incoming rainfall with minimal effect on the air stream. The A4SHP is AMCA rated for Air Performance and Water Penetration with a beginning point of water penetration of 990 FPM. Add flanges to the frame for a seamless look between the louver and the opening.
Know your requirements first. If you don’t need severe weather protection, then consider adding non-drainable louvers built for airflow. Choose the louvers you need to meet the project’s requirements.
IL31A by Louvers & Dampers
There may be times when you need to close off a ventilation point. You can install a control damper behind a louver to achieve this. The more cost-effective option is an adjustable louver. Adjustable louvers can rotate their blades to open or close an opening. When open, the blades maintain a pre-determined blade angle to deflect rainfall. Certain adjustable louvers will also have drainable blades, so you can minimize water infiltration when the louver is open.
The IL31A by Louvers & Dampers is an adjustable, drainable louver. This louver has drainable baffle blades that capture rainwater and direct it to drain channels in the jambs. These blades can rotate to close the opening when airflow stops. The IL31A comes with silicone rubber blade seals and polyurethane jamb seals for tight closure. Keep rain out while the louver is closed.
Louvers are usually installed in inaccessible areas of the building. Add an electric actuator to automate blade rotation. This actuator type allows the louver to open or close without an operator present. With an electric actuator, you can signal the louver to close at any time. Read more about electric actuation in this article.
If you want the option to close ventilation openings, consider adding an adjustable louver like the IL31A. Adjustable louvers provide the benefits of a louver-damper combo without the added cost of separate units.
The first step is knowing what to look for. Know the requirements before you select a louver. Once you know what you need, then you can check the louver’s submittal. Make sure the louver will meet your project’s needs.