With an emphasis on green building, each new design is more cognizant about the surround environment and how it affects the building and its occupants. The sun can be one’s best friend by being able to harness its energy through the use of photovoltaic panels, or using it to provide natural lighting. However, on the opposite side the sun and its heat can negatively affect the building systems by adding cost as well as negatively affecting building occupants’ overall satisfaction. Exterior sun control devices may be used as a means to help protect a building and it’s occupants from the negative affects of the sun. By effectively using exterior sun control devices a building is able to save money and create higher occupant satisfaction.
Energy Savings
Cooling costs account for nearly a quarter of all the building’s energy costs, second to space heating. By preventing the direct transmittance of light and heat into the building, sunshades are an effective strategy to lower cooling costs. While exterior sun control devices block direct sunlight from entering the building, they still allow natural ambient light in, thus reducing the need for artificial lighting, which accounts for another significant energy cost. Artificial light is also a major contributor to heat, thus increasing cooling costs as well.
Not Just About Energy Savings
Employee satisfaction surveys often show that environmental comfort of a workspace can have an impact on employee satisfaction and productivity. Being too hot or too cold can serve as a distraction causing employees to focus their attention to their lack of personal comfort instead of the task at hand. Direct sunlight or glare may also cause undue eyestrain, which may lead to discomfort and fatigue. By including exterior sun control devices the window may also be free from internal shading devices, such as blinds or roller shades, thus providing a direct line of sight to the outdoor space. Multiple studies have shown that having a connection to outdoor spaces increases occupant satisfaction, especially those with flora or fauna.
Strategies
Louvered sunshades are the most effective exterior sun control device. Typically fabricated from aluminum sunshades are lightweight and hold up to the most extreme weather conditions. Louvered sunshades are also ideal over canopies in the sense that they allow air, water, snow and ice to pass through, thus reducing the loads imposed on the building and the need for additional unnecessary structural support.
Louvered sunshades may be installed in horizontal or vertical orientations, typically on the south or west elevation. Exterior sun control devices should be designed based on geographic location, building orientation and size of the window. Typically sunshades are designed to prevent direct sunlight from passing through the sunshade at the peak sun angle on June 21.
Fabrication
Sunshades are fabricated utilizing only a few components, typically extruded aluminum. Blades are the term used to describe the slats or vanes that make up the sun-blocking component. Blades are available in a variety of shapes (tubular, louver, airfoil) and sizes. Other materials in lieu of blades may be used as a shading component. Perforated metals, egg crate grilles and photovoltaic panels may be used as shading elements. The fascia is the front outermost component of the sunshade.
Typical shapes include tubes, bullnoses or wedges. Outriggers are the arms that cantilever out from the building that capture the blades and fascia. Outriggers may be straight or tapered, flat bar, tube or channel. Lastly, mounting brackets are used to install the sunshade to the wall. These brackets are often custom fabricated to integrate with the building substrate. All components are joined together using mechanical fasteners that allow for a clean appearance between points. Mechanical fasteners have also been proven to be a stronger connection than welding, as aluminum may weaken when the heat from welding is applied.
Design Considerations
As mentioned previously, geographic location plays an important role in the design of the sun control device. It is important to work with a professional engineer who is licensed in the jurisdiction of where the project is located to ensure that the specific design criteria and loads have been taken into account. Fasteners into surrounding conditions, while not typically provided by the manufacturer, should be selected based on the calculations provided by the engineer.
Being Green
Adding exterior sun control devices to a design can help a building earn LEED certification. The following areas where sun control devices can contribute to LEED points are: Sustainable Sites, Energy & Atmosphere, Materials & Resources and Indoor Environmental Quality.
Many louver manufacturers have segued into manufacturing exterior sun control devices as the components are similar. Industrial Louvers has been manufacturing louvers, equipment screens and sun control devices for more than 40 years. Being able to provide unique products and unique solutions specialized for an individual building ensures successful project delivery.
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Brett Reinhardt is the marketing manager for Delano, Minn.-based Industrial Louvers Inc. To learn more, visit www.industriallouvers.com.