OHL-DRC
Drainable Closable Louver

The Holyoake OHL-DRC is a precisely made closable, drainable, weather louver. It is constructed from extruded aluminium in a channel or flanged frame, with special interlocking closable blades gang operated by either manual or motorised means.
The blades feature a special gutter, so each blade only deals with the water that lands directly onto it. Therefore, water does not stream down the front of the louver, but is directed by means of this gutter on the leading edge of each blade, to the external base of the louver.
In addition to the drainable blades the OHL-DRC also offers the unique combination of a closable louver, operated by a manual handle, or via a motor. This provides the facility to fully, or partially close the louver automatically, when linked to a moisture, or rain sensor, or other building management system.
On a typical horizontal louver, where water cascades down the face, the water builds to a level where the pressure differential and the velocity of air over the louver, is enough to carry over the water to the inside of the louver.
By avoiding this effect the OHL-DRC Drainable Closable louver offers excellent performance, so there is much less water intrusion at a given level and a higher effective velocity can be used, without compromising the water penetration performance. While open, they offer minimum airflow resistance, with low droplet penetration for normal weather.