Designing Dynamic Metal Canopies

by Mark Robins | February 1, 2021 12:00 am

They set the mood or atmosphere of a building; they can give businesses a unique and identifiable look. Business names, logos and other eye-catching designs can be printed on them, providing a cost-effective covered space with company identification.

Metal canopies create a fluid extension of a building without the expense of adding on rooms. “A canopy extends the habitable area of a building, expanding its footprint in a subtle, inferential way,” says Whitney Sander, principal, Sander Architects[2], Marina del Rey, Calif. “With this expanded footprint, the building ‘precinct,’ or area of protection, is larger. If we consider that the area of a building is that space with the building conditions—passively in this case—then the building area includes the canopy-covered areas adjacent to it.”

When people approach a large building and wonder where the entrance is, they immediately begin to understand the role that canopies play. Canopies help direct people along pathways. “Canopies help declare the entry and oftentimes give buildings their identity, acting as the welcome mat for the front door,” says Craig Rizzo, architectural designer and principal at ZGF Architects[3], Seattle. “Metal canopies invite patrons in, providing a level of engagement and protection.” Brent A. Schipper, AIA, principal, ASK Studio[4], Des Moines, Iowa, agrees, saying, “The canopy is the first cue to the spirit of a building. It begins the narrative at the critical moments of entry.”

In addition to entrances, canopies can provide weather protection by covering diverse areas like gas station fueling areas, outdoor cafés and drive-through windows. Sander says canopies “have historically offered a lighter-impact place of protection from weather elements adjacent to buildings.” They can block the sun’s heat and ultraviolet light, and also give shelter from rain, wind, sleet or snow at drop-off areas as occupants or visitors transfer from a vehicle to a building. Because they can absorb some of the sun’s heat, air-conditioning energy costs are lessened.

“In essence, canopies create semi-protected, intermediate zones between the exterior environment and the building interior,” says Alex Korter, AIA, RIBA, LEED AP BD+C, principal at CO Architects[5], Los Angeles. “Canopies are often also used in landscape areas or on rooftops or terraces to provide shade, and define seating and social areas for occupants to enjoy.”

CANOPY DESIGN ADVICE

There are many considerations, variables and challenges associated with canopy design. “Given the available metal profiles available, textures and colors, the possibilities are infinite,” Rizzo says. “Canopies are a great opportunity to express a little playfulness.”

Schipper believes that, “Metal allows the designer to be challenged and challenge what is common, for example: gravity. Through the use of stock shapes and common fabrication techniques, the canopy design can provide an identity for a building.” Schipper has been designing his canopies with plate steel as the roof membrane with an elastomeric coating. He says the use of plate steel adds to the illusion of floating planes in that the membrane has a thin profile.

When designing canopies, be aware of the effect they will have on the overall presence of a building. “Canopies can have a substantial impact on the design reading of a building,” Sander says. “They are often the first building elements experienced on the approach to a structure, and therefore have a greater effect on the perception one has of the structure. Similarly, a human eyelash with substantial eyeliner might enhance an eye, and could greatly change the experience of a face.”

One of the challenges in canopy design is making the supporting structure as elegant, integrated and as light as possible to emphasize the horizontal surfaces canopies create. “Since canopies often need to provide shelter from the rain, integrating the drainage strategy to get rainwater off the canopy is also something to be considered and addressed in the design right away,” explains Korter. “This is especially important since most canopies need to be designed to shed water in a closed drainage system including gutters and downspouts and not just shedding water off the edges. The seamless integration of lighting, signage and sprinklers (where applicable) into the design is also often a challenge and requires very close coordination with the supporting structure design.”

In addition to determining the level of protection against rain, wind and daylight filtration need to be considered. “It’s all about the details and the first impression,” Rizzo notes. “How to keep a canopy elegant, lightweight and on budget, all play into the design. Other considerations that are important drivers are managing water, necessary clearances, and most of all, ease of maintenance. Canopies need to perform but also need a durable life span, and that’s where the right choices come into mind regarding metal profile, thickness and durable detailing. It’s front and center.” Canopies can be attached or freestanding add-ons to buildings. Schipper explains there are often either structural reasons or code reasons to keep the canopy a freestanding entity. “Canopies that are not part of the building structure may be allowed to refrain from sprinklers if built with non-combustible construction as afforded by metal. Canopies often have lesser structural requirements than occupied structures so there are inherent differences in stiffness and movement that must be isolated. Whether attached or detached, the canopy must be part of the building narrative and not simply a covered walk.”

Douglas V. Pierson, AIA, LEED APBD+C, professor of practice, NC State School of Architecture and co-founder/partner, architect and design principal at pod architecture + design[6], Carrboro, N.C., stresses that with many canopy design considerations, canopies must still be designed to be integral to the overall building. “One of the biggest challenges of integrated canopies is the perceived added cost; however, if they are woven into the overall fabric of the building, the work, materials and trades are already baked in to the overall construction and cost is mitigated. Nonetheless, a commitment by the client is essential.”

THE FABRIC OF CANOPIES

A growing design trend is using alternative materials to provide more malleability and flexibility in canopy geometries. “Using more lightweight materials such as fabrics, mesh or perforated, and folded panels reduce the size of the supporting structural members,” Korter says. “Using fabric, mesh or other architectural metals for canopies can create a more holistic approach by closely integrating metal canopies with the façade design and help contribute to the overall building performance.”

Sander calls woven wire metal fabrics a wonderful, durable way to provide shade protection in lieu of a traditional fabric canopy. “In metal fabrics, fine wires—and even flat steel ribbons—are woven into meshes of various types and complexities. Some metal fabric meshes are quite intricate in their pat – terns. Fabrication technology has advanced sufficiently that these products are produced by substantial machines to provide near-perfect, repetitive patterns of different thickness and materials. By contrast, traditional fabric canopies have some advantages: they are pliable, almost lyrical in their curved, sensuous forms. If they are treated with a plastic (or similar waterproof) coating, they also provide rain/snow protection, which woven steel wire fabrics do not entirely. Both metal fabric and traditional fabric options are currently in broad use, and each product is continuously being improved in fabrication and performance characteristics.”

Rizzo believes with metal design and fabrication processes creating more complex geometries, there’s really no limit to the imagination. “Fabric architectural metals are being tested to push form and ease of fabrication. It’s always inspiring to see what designers and fabricators are doing today—pushing the limitations on materiality and connections. Where metal once had the tendency to be more assertive, compared to common fabric awnings for example, innovations today allow for a lighter and more delicate play on what metal canopies can offer. Sometimes seemingly more complex or expensive, they can prove to be achievable and efficient through fabrication and simplification of construction, allowing for more permanence and longevity over time. Execution, proper detailing and careful choice in metal use can allow for wonderful playful opportunities.

Source URL: https://www.metalarchitecture.com/articles/designing-dynamic-metal-canopies/

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