{"id":22615,"date":"2016-12-12T12:30:41","date_gmt":"2016-12-12T17:30:41","guid":{"rendered":"http:\/\/www.constructionspecifier.com\/?p=22615"},"modified":"2017-06-08T09:20:07","modified_gmt":"2017-06-08T13:20:07","slug":"open-up-your-knowledge-of-operable-wall-louvers","status":"publish","type":"post","link":"https:\/\/www.constructionspecifier.com\/open-up-your-knowledge-of-operable-wall-louvers\/","title":{"rendered":"Open up your knowledge of operable wall louvers"},"content":{"rendered":"
\"When
When airflow control is of utmost importance, an operable wall louver is an ideal solution. When combined with fixed louvers as a dual-blade operable louver, these offer design and performance flexibility.<\/span>
Photo \u00a9 BigStockPhoto<\/em><\/figcaption><\/figure>\n

by Kristi Duce, CCS, GGP, CSI, AIA, NCARB<\/strong><\/p>\n

Operable wall louvers offer maximum flexibility for airflow control, design, and functionality. To control airflow, these \u2018adjustable\u2019 wall louvers contain blades that typically rotate within the louver frame between fully open at a preset angle and fully closed. In some cases, the operable blades may be the only set of blades within the louver frame. In dual-blade operable (or \u2018combination\u2019) louvers, however, they are in addition to the set of fixed blades.<\/p>\n

For cases where climate conditions preclude single louvers, dual-blade operable units allow aesthetic needs to be met while maintaining functionality and weather protection. If aesthetics is a concern due to the high visibility of a louver, a dual-blade unit with a fixed louver on the exterior can offer consistent appearance regardless of the interior blade\u2019s position.<\/p>\n

When severe weather is a concern, operable louvers should not be specified as a single unit, as they typically cannot withstand windborne-debris impact and are ineffective at resisting wind-driven rain. Instead, one can opt for a dual-blade model with a fixed louver capable of enduring these conditions on the exterior, and an operable blade on the interior for airflow control.<\/p>\n

If the operable louver location makes security is a concern, a dual-blade louver can be used with a fixed-blade louver on the exterior attached with security screws or concealed fasteners. Several other combinations of dual-blade louvers are available, or one can be created by using any type of fixed blades combined with operable blades in the same frame.<\/p>\n

The blades on operable louvers can be operated by cranks, push bars, chains, or actuator devices that are electrically, pneumatically, or hydraulically powered. The louver location and function generally dictate the operation type required.<\/p>\n

Operable louvers can be drainable-blade or non-drainable-blade. The former is designed with gutters to collect water falling on the blade and drain it to the blade ends. There, it flows in the channels of vertical frame members to the bottom of the louver and is weeped to the exterior. Non-drainable blades, on the other hand, allow the water falling on the blade to flow down its face to the louver face and then drip off\u2014frequently to be blown onto the blade below.<\/p>\n

Operable louver performance is measured by the following factors:<\/p>\n