Drainable louvers keep interiors dry, but how do they “drain” rainwater? Learn where the water goes with this quick Condenser read.
Non-drainable louvers can protect an opening from the rain. All louvers utilize angled blades that deflect rainfall while allowing air through the louver’s free area.
This image highlights the drain channels found in the louver's jambs.
In light rain, the rainwater will naturally slide off the angled blades and down the face of the louver. The water falls off the blades at the sill and away from the opening.
But this drainage will create a waterfall effect if the rain picks up, which collects along the lower row of blades. This increases the risk of water infiltration.
Drainable blades have troughs that prevent spillages across the face of the louver. Instead, the water is directed to channels in the louver’s jambs. If you look at the inside of the louver’s jamb, then you will see these channels line up with the drain troughs. The image above has the channels highlighted.
The jamb channel will often look like a depression in the jamb that runs the full height of the louver. The water falls down the louver through these channels, directly to the louver’s sill.
Drainable blades have troughs along the face side of the blade. The troughs capture water before it slides off the blade.
This eliminates the waterfall effect and drastically reduces the risk of water penetration. From there, the sloped interior of the sill directs the water out of the louver. The water will typically follow the wall to the ground below.
In severe weather, excess water can collect at the sill. If it rains hard enough, it can potentially flood the sill and cause the water to spill through the louver.
Drain pans block the sill section along the back side of the louver, which prevents backsplash into the space behind the louver. It also provides an additional space for rainwater to collect in the louver.
Drain pans are open along the face side of the louver and provide a slope for collected water to fall out of the louver.
This design also helps prevent the cascade effect between louvers by providing a longer ramp for drainage. This keeps the water away from the wall, so that it doesn’t fall into any louvers below.
Proper louver drainage is important. Water damage at ventilation points can be difficult and costly to fix. Choose the right louvers to protect your project.
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