LOUVERS FAQs

A:Mill finish aluminum is raw or unfinished material. This material is commercially smooth and substantially free from blisters, inclusions, voids, slivers and kinks. Slight discontinuity resulting from flow and die lines inherent in the extrusion process will exist. Occasional discontinuities removed easily making the surface suitable for finishing operations are acceptable. Although aluminum is naturally resistant to corrosion, its appearance will change because of weathering and aging. Coloration and sheet will vary over time. Mill finish products may have a non-uniform surface appearance resulting from oil, heat and oxide discoloration that is inherent in the manufacturing process.

A:With respect to louver products, pressure drop is a measure of airflow resistance typically displayed as inches of water gauge at specific free area velocities. Free area and the aerodynamic properties of the louver product are among items that play a part in determining pressure drop. Lower pressure drop is generally considered more advantageous. Note that high free area is not necessarily synonymous with low-pressure drop. AMCA 500-L prescribes the method for determining louver pressure drop.

A:A drainable blade louver, such as Greenheck series ESD or EDD, incorporates horizontal drain gutters on the front or leading edge of the louver blade. The intent of a drainable blade louver is to mitigate the cascading of water down the face of the louver. Water that collects in the horizontal drain gutters channels to the vertical downspouts located in the louver jambs (sides). Once water reaches the vertical downspouts, gravity takes effect and the collected water escapes at the louver sill (bottom). Drainable blade louvers provide good water rejection properties, but lend little defense against wind driven rain.

A:With respect to louver products, the AMCA Listing Program is reserved for the AMCA 540 debris impact test and the AMCA 550 High Velocity Wind Driven Rain test. Unlike the AMCA 500-L test procedures, AMCA 540 and AMCA 550 are “pass/fail” criteria test procedures. By displaying the AMCA Listing label AMCA is certifying that the louver product(s) in question have passed the AMCA 540 and/or AMCA 550 standard. The AMCA 540 and/or 550 standards are requirements for the Hurricane Prone Region as defined by the International Building Code.

A:AMCA is the Air Movement and Control Association International. The mission of AMCA International is to promote the health and growth of the industries covered by its scope and the members of the association consistent with the interests of the public. AMCA develops industry related test standards for air movement and control products while independently certifying product performance to ensure reliable and accurate product performance. For more information about AMCA please visit www.amca.org

A:Our average lead-time for standard catalogued products is four weeks for mill finish products. Production lead-times may fluctuate depending on order size, seasonality and/or backlog. Orders that require special design requests (SDR’s) will have longer than average lead-times.

A:Free area is the available open area of a louver that is not impeded by the louver components. Louver frame depth, component profiles, louver blade spacing and louver blade angle all play a role in determining the louver free area. AMCA publication 500-L prescribes the method for determining louver free area. A far too often used rule of thumb is “50% free area”. The percentage of free area is not consistent from size to size. This holds true for all manufacturers. As an example, Greenheck model ESD-403 offers 50% free area based on a 48 in. x 48 in. size. The same louver offers only 30% free area for a 12 in. x 12 in. size. The very same louver offers 54% free area for a 120 in. x 120 in. size. Greenheck does not recommend specifying louvers based on an assumed percentage free area.

A:No louver may be considered 100% waterproof or stormproof. Depending on the louver type, application and configuration Greenheck recommends sizing conventional intake louvers at or around 75% of the products capacity with the capacity defined as the “Beginning Point of Water Penetration”.