Shading with Metal Louvers and Canopies

by Mark Robins | February 1, 2022 12:00 am

To do this, shading devices such as louvers and canopies have become a critical tool for architects when designing energy-efficient buildings. Shading reduces a building’s overall cooling requirement and emissions, and saves energy as a result.

Solar shading optimizes building performance and is a must for all sustainably minded building design. “Integrated façade elements like louvers and canopies can be the basis for a building’s exterior design, and offer a poignant contrast to both glazing and opaque cladding, all while making the facility more energy efficient,” says Colin Drake, AIA, LEED AP, principal, JRA Architects[2], Louisville, Ky. “A building’s south façade can be calibrated to shield glazing from all warm season, direct sunlight, while allowing it to enter for passive heating in cooler seasons.”

“Sunshades are primarily used to contribute to LEED requirements, helping to lower a building’s solar heat gain coefficient,” says Varun Patel, business development manager of architectural grilles and shading, Construction Specialties Inc.[4], Lebanon, N.J.

The two most important factors in shading design are seasonal sun angles and location.
Michael Bradley, CEO, MASA Architectural Canopies, Piscataway, N.J.

Travis Wendt, owner and president of Houston-based Metallic Products Corp.[6], explains that in certain areas along the West Coast, California in particular, shading requirements are now incorporated into building codes. “In other words, these considerations are no longer simple goodwill efforts to keep spaces more comfortable. They’re legal requirements a design team must factor in when it comes time to get the ball rolling on projects in specific areas.”

SPECIFIC SHADING SOLUTION

Shading is not a one-size-fits-all issue. Each individual building project requires a shading solution specific to that building’s needs. Each sunshade must be an exact fit for the area it protects.

Knowing sun angles is vital. “The sun’s path across the sky is so consistent that designers can control the light very precisely, with varying effects throughout the year,” Drake says. “Façade orientation and the incident sun angles are everything to properly designed solar shading. It’s imperative to consider the range of sun positions throughout the day and year to optimize performance and occupant comfort.”

“Each building must be protected in the correct locations,” explains Michael Bradley, CEO of MASA Architectural Canopies[7], Piscataway, N.J. “A randomly constructed piece will never achieve the full potential benefits. Something that almost fits means that it almost works. The two most important factors in shading design are seasonal sun angles and location. A sunshade must be constructed to address the Azimuth angle—the compass direction from which the sun strikes the building. Understand that the sun is not a light bulb. It doesn’t act the same way in every situation. Therefore, sun shading must be specific. Consider which sides and/or corners of the building need protection. Also, don’t get stuck on the first floor. Stacking sunshades up to the top floor of the building can exponentially increase benefits. Sunshade planning comes down to knowing the needs of your building and addressing them.”

“When you specify proper shading, not all sun rays will reach the interior, improving occupant comfort and lowering energy costs,” adds Patel. “That said, on east and west elevations horizontal or vertical line sunshades are most effective. On the south side of a building, specifiers should consider shading devices that project outward at least 3 to 4 feet. Careful consideration of the sun’s movement allows building owners to maximize sunlight where desired and protect against it elsewhere. All these considerations contribute to reducing heating and cooling costs, lowering a building’s overall carbon footprint.”

FLEXIBLE, DYNAMIC SHADING SOLUTION

A flexible shade system can block the sun or let it in, as needed, for effective energy conservation. Metal louvers have changed the way shade can be delivered. “Rather than pergolas being made of wood—or stone if you want to look way back in history—and other heavy materials that, once installed, didn’t move, the use of metal frames that can hold pivotable metal louvers has made shading for buildings more versatile,” says Scott Selzer, founder and CEO of StruXure[1], Dahlonega, Ga. “The sun doesn’t stay in one location all day. Having a product that can adjust to the sun’s movement provides a much more effective shade solution.”

An automated shading product, like StruXure’s Perogla X, provides more than shade. It provides protection from wind and rain; Selzer calls it interactive and smart. “On the other hand, a static product is limited: a fixed, angled-slat pergola, for instance, only provides shade at certain times of day, and no protection from rain; and a static canopy-style structure is equally one-dimensional in its functionality.” Also, many shading materials are made of aluminum, a sustainable product. “Aluminum is recyclable,” Selzer adds. “We have recycled nearly 1 million pounds of materials in the last 12 months alone.”

Bradley agrees dynamic shading devices are useful but cautions they come with their own challenges. “The cost to build and install adjustable pieces, and potentially electronics, can be prohibitive. Also understand that adjustable devices will require maintenance, upkeep repair, or replacement of parts over its life span. A well-built fixed device will consistently perform it job simply and cost effectively.”

Patel cautions the biggest barrier to dynamic shading is the expense. “Dynamic shading devices typically have a higher price tag and operate with motors that need repair and maintenance over time. This results in a higher cost up front and a more costly life cycle. Fixed shading devices are less expensive than dynamic devices and rarely need repair or maintenance.”

Wendt believes the key consideration when determining whether to go fixed or dynamic is to think through the end user’s experience and the amount of maintenance they’re willing to put in. “If the customer is more a ‘set it and forget it’ type of person—and we find that many are—fixed is the way to go. There’s little to no maintenance as opposed to dynamic iterations which feature moving parts that can wear out and break.”

CANOPY SHADE

Architectural canopies have multiple applications: walkways, doorways and windows. A canopy located strategically above a building’s air conditioning unit helps lower operating costs by keeping the unit shaded from direct sunlight.

Also, canopies can also help protect the unit from leaves, dirt and debris that can clog its elements and lower efficiency. Canopies above windows help keep indoor temperatures more comfortable, lessening the need for thermostat adjustments.

Wendt advises making sure the chosen canopy is built to last for the long haul. “If the building is in an area regularly impacted by frigid winters or high winds, you’ll need to opt for a sturdier canopy to protect both the structure and the people who visit it. In the metal building world, we find that customers are interested in shading options that work smarter, not harder. If a building canopy can pull double duty in some way—keeping an area cooler during the daytime and providing outdoor lighting in the evening, for instance—people tend to view it as a better investment. Aesthetically pleasing designs with complementary colors and finishes help, too. Everybody wants their building to look nice.”

Jim Leslie, general manager of Pittsburgh-based EXTECH/Exterior Technologies Inc.[8], explains to maximize effective shading with canopies, design teams should involve manufacturers early in their project’s development, when it’s the least costly to explore options and overcome limitations.

“This early involvement and design assistance from the manufacturer will ensure the project’s relevant codes, standards and performance requirements are met, as well as the desired appearance, budget and schedule. A few manufacturers can provide an all-in-one turn-key solution: from canopy design through installation, saving time, cost and frustration.”

To enhance canopies, perforated metal is being used as a decorative material. “A canopy with perforated metal allows the sunlight to shine through, creating aesthetically pleasing light and shadow patterns,” Bradley says. “It is a useful tool in daylighting design.”

Drake explains that, “Perforated metal is an excellent alternative to more conventional shading systems by allowing the design team to prescribe the optimum amount of light admitted through the façade, and the quality of view created when the cladding is paired with glazing. There are any number of remarkable visual effects that can be created using perforated panels in high visibility portions of the building.” Selzer cautions that while perforated metal used in shading applications can regulate both ventilation and sunlight, it does not; however, offer the protection and flexibility of automated, solid metal panels.

Source URL: https://www.metalarchitecture.com/articles/shading-with-louvers-and-canopies/

---