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The eyes may be the window to the soul, but doors and windows are often the heart of a building, providing everything from daylight to access and functionality. Whether it’s aesthetics or performance, fenestration options can have a profound and transformative impact on building design. In order to make the wisest decisions, architects need to stay informed about the latest trends, innovations, and performance requirements as well as understand how to maximize efficiencies in their next project.
This course will look at a wide variety of innovative fenestration products, systems, solutions, and trends that affect the design, functionality, and overall long-term success of today’s built environment—everything from material selection to code compliance.
© Fernando Alda
Fixed and sliding units bring beauty and function to this spacious, minimal residence, located in Spain.
Design and Performance Trends
Meeting Codes for Minimal Framing and All-Glass Aesthetics
A prominent trend in architecture today focuses on facades and fenestration systems that feature minimal hardware and all-glass aesthetics. When specifying these types of systems, however, architects are faced with the challenge of meeting energy codes. Codes are also becoming more stringent nationwide, as is exemplified in California Title 24.
“Understanding the fenestration code compliance process and the documentation required can be a challenge,” says CRL – U.S. Aluminum FenestrationMaster® and Director of Product Testing and Certification Ron Wooten. He advises, “Check with the local code authorities to determine the requirements as early as possible in order to avoid complications down the road.”
Advances in fenestration thermal performance are helping to alleviate the situation. Some new thermal entrance systems, for instance, offer sought-after all-glass aesthetics using ultra-narrow (as thin as 11/8-inch) vertical stiles and a low overall system depth (some only 2½ inches). In addition, select systems have the unique ability to support handle hardware on 1-inch insulating glass using proprietary through-glass fittings. This produces a streamlined “floating on air” visual. Despite its all-glass aesthetics, such a system can deliver U-factors as low as 0.43 using thermally broken framing and cladding, allowing it to comply with strict energy codes.
Butt-glazed curtain wall systems with no exposed exterior vertical mullions or joint fasteners can also provide uninterrupted horizontal glass spans that produce clean, all-glass visuals. Some have a double thermal system with 1-inch insulating glass, allowing them to deliver exceptional thermal performance to meet code. One manufacturer’s product features a polyurethane thermal break and a unique injection-molded thermoplastic connector that produces superior thermal isolation. This type of butt-glazed curtain wall system is ideal for retrofit applications because its clean sightlines can achieve an all-glass aesthetic while simultaneously meeting energy codes. Systems should be tested using standardized performance tests to ensure strength and durability.
© Geoff Captain
This thermal entrance produces all-glass aesthetics via ultra-narrow (as thin as 11/8-inch) vertical stiles and the unique ability to support handle hardware—including panic devices—on 1-inch insulating glass.
Codes and Energy Performance
Achieving the desired aesthetic is just one piece of the puzzle. With any project that involves fenestration—whether it’s new construction or a retrofit application—architects must be aware of the local codes that specify energy performance requirements and understand the NFRC’s role in complying with these codes. They should only work with fenestration system manufacturers that can supply the necessary documentation, such as NFRC Bid Reports and Label Certificates. Some manufacturers will also provide State Energy Commission Document Coordination and hardware consultations. Partnering with local code authorities in the early stages of the design process is also advised.
In retrofit applications, architects should know that although performance requirements for existing fenestration components can sometimes be grandfathered in, new systems must comply with the energy codes of local jurisdictions.
Fire-Rated Safety Glass
Another performance feature manufacturers may offer is superior fire-resistant and fire-protective safety glass, including fire-rated doors, systems, and curtain walls; intruder-, impact-, bullet-, and hurricane-resistant glass; and other clear fire-rated glazing products that protect from 20 to 180 minutes. Often, these products combine a minimalistic appearance with maximum safety and performance.
Wireless Alternatives
Why fire-rated glass? Because of Building Code Requirements. But today, you have a choice of products that offer higher performance and human safety while still meeting building code requirements. You can achieve a better design aesthetic with larger sizes that allow you to specify a passive rather than active system, such as sprinklers. Clear glass also allows you to bring light into your spaces.
Photos courtesy of Olaf Rohl, 2015 (left); Robert Steve, 2017 (right)
Fire-rated glass offers high performance and design flexibility while maintaining strict building code requirements. Shown here, The Fairmont Hotel in Vancouver, British Columbia, Canada (left); CCU I-study corridor, Coastal Carolina University in Conway, South Carolina (right).
Features and Benefits of Fire-Rated Glass
Innovations in glazing technology and materials have dramatically changed the industry, bringing several benefits to architects, designers, and building owners:
Expanded Fields of Use
- Longer fire ratings and larger-sized glass
- Higher degrees of fire resistance/protection
- Application-adapted performance
- Accidental human impact solutions
Multifunctional Features
- Visual clarity
- Sound reduction
- Decorative and privacy treatments
- Solar and thermal insulation
- Explosion resistance
- Bullet resistance
- Hurricane resistance
- Seismic rating
Daylighting for Energy Efficiency
Using fire-rated glass is also an excellent way to harness natural daylight in open-plan building designs while ensuring fire safety and energy savings, reducing the need for artificial light, reducing carbon footprint, and cutting heating and cooling costs. In exterior applications, these products may be incorporated into double and triple glazing with solar control and low emissivity features, which allows for the most amount of light while maintaining the energy performance of a building.
With the number of new glazing products available and the advancement of production technologies, the design possibilities continue to grow. Products now exist to accommodate virtually every condition, thus allowing the architect/designer to satisfy cost and performance objectives without sacrificing design or code compliance.
Photo courtesy of Olaf Rohl
Fire-rated glass can be used to harness natural daylight while ensuring fire safety, minimizing the need for artificial light, and cutting heating and cooling costs. Shown here is the Verizon Flagship Store, Chicago.
The eyes may be the window to the soul, but doors and windows are often the heart of a building, providing everything from daylight to access and functionality. Whether it’s aesthetics or performance, fenestration options can have a profound and transformative impact on building design. In order to make the wisest decisions, architects need to stay informed about the latest trends, innovations, and performance requirements as well as understand how to maximize efficiencies in their next project.
This course will look at a wide variety of innovative fenestration products, systems, solutions, and trends that affect the design, functionality, and overall long-term success of today’s built environment—everything from material selection to code compliance.
© Fernando Alda
Fixed and sliding units bring beauty and function to this spacious, minimal residence, located in Spain.
Design and Performance Trends
Meeting Codes for Minimal Framing and All-Glass Aesthetics
A prominent trend in architecture today focuses on facades and fenestration systems that feature minimal hardware and all-glass aesthetics. When specifying these types of systems, however, architects are faced with the challenge of meeting energy codes. Codes are also becoming more stringent nationwide, as is exemplified in California Title 24.
“Understanding the fenestration code compliance process and the documentation required can be a challenge,” says CRL – U.S. Aluminum FenestrationMaster® and Director of Product Testing and Certification Ron Wooten. He advises, “Check with the local code authorities to determine the requirements as early as possible in order to avoid complications down the road.”
Advances in fenestration thermal performance are helping to alleviate the situation. Some new thermal entrance systems, for instance, offer sought-after all-glass aesthetics using ultra-narrow (as thin as 11/8-inch) vertical stiles and a low overall system depth (some only 2½ inches). In addition, select systems have the unique ability to support handle hardware on 1-inch insulating glass using proprietary through-glass fittings. This produces a streamlined “floating on air” visual. Despite its all-glass aesthetics, such a system can deliver U-factors as low as 0.43 using thermally broken framing and cladding, allowing it to comply with strict energy codes.
Butt-glazed curtain wall systems with no exposed exterior vertical mullions or joint fasteners can also provide uninterrupted horizontal glass spans that produce clean, all-glass visuals. Some have a double thermal system with 1-inch insulating glass, allowing them to deliver exceptional thermal performance to meet code. One manufacturer’s product features a polyurethane thermal break and a unique injection-molded thermoplastic connector that produces superior thermal isolation. This type of butt-glazed curtain wall system is ideal for retrofit applications because its clean sightlines can achieve an all-glass aesthetic while simultaneously meeting energy codes. Systems should be tested using standardized performance tests to ensure strength and durability.
© Geoff Captain
This thermal entrance produces all-glass aesthetics via ultra-narrow (as thin as 11/8-inch) vertical stiles and the unique ability to support handle hardware—including panic devices—on 1-inch insulating glass.
Codes and Energy Performance
Achieving the desired aesthetic is just one piece of the puzzle. With any project that involves fenestration—whether it’s new construction or a retrofit application—architects must be aware of the local codes that specify energy performance requirements and understand the NFRC’s role in complying with these codes. They should only work with fenestration system manufacturers that can supply the necessary documentation, such as NFRC Bid Reports and Label Certificates. Some manufacturers will also provide State Energy Commission Document Coordination and hardware consultations. Partnering with local code authorities in the early stages of the design process is also advised.
In retrofit applications, architects should know that although performance requirements for existing fenestration components can sometimes be grandfathered in, new systems must comply with the energy codes of local jurisdictions.
Fire-Rated Safety Glass
Another performance feature manufacturers may offer is superior fire-resistant and fire-protective safety glass, including fire-rated doors, systems, and curtain walls; intruder-, impact-, bullet-, and hurricane-resistant glass; and other clear fire-rated glazing products that protect from 20 to 180 minutes. Often, these products combine a minimalistic appearance with maximum safety and performance.
Wireless Alternatives
Why fire-rated glass? Because of Building Code Requirements. But today, you have a choice of products that offer higher performance and human safety while still meeting building code requirements. You can achieve a better design aesthetic with larger sizes that allow you to specify a passive rather than active system, such as sprinklers. Clear glass also allows you to bring light into your spaces.
Photos courtesy of Olaf Rohl, 2015 (left); Robert Steve, 2017 (right)
Fire-rated glass offers high performance and design flexibility while maintaining strict building code requirements. Shown here, The Fairmont Hotel in Vancouver, British Columbia, Canada (left); CCU I-study corridor, Coastal Carolina University in Conway, South Carolina (right).
Features and Benefits of Fire-Rated Glass
Innovations in glazing technology and materials have dramatically changed the industry, bringing several benefits to architects, designers, and building owners:
Expanded Fields of Use
- Longer fire ratings and larger-sized glass
- Higher degrees of fire resistance/protection
- Application-adapted performance
- Accidental human impact solutions
Multifunctional Features
- Visual clarity
- Sound reduction
- Decorative and privacy treatments
- Solar and thermal insulation
- Explosion resistance
- Bullet resistance
- Hurricane resistance
- Seismic rating
Daylighting for Energy Efficiency
Using fire-rated glass is also an excellent way to harness natural daylight in open-plan building designs while ensuring fire safety and energy savings, reducing the need for artificial light, reducing carbon footprint, and cutting heating and cooling costs. In exterior applications, these products may be incorporated into double and triple glazing with solar control and low emissivity features, which allows for the most amount of light while maintaining the energy performance of a building.
With the number of new glazing products available and the advancement of production technologies, the design possibilities continue to grow. Products now exist to accommodate virtually every condition, thus allowing the architect/designer to satisfy cost and performance objectives without sacrificing design or code compliance.
Photo courtesy of Olaf Rohl
Fire-rated glass can be used to harness natural daylight while ensuring fire safety, minimizing the need for artificial light, and cutting heating and cooling costs. Shown here is the Verizon Flagship Store, Chicago.
High-Performance Grilles and When to Use Them
High-performance grilles can provide a number of advantages for such applications as parking garages, storage facilities, and a host of other building types. Benefits include aesthetics, security, and visibility. High-performance grilles not only provide valuable functionality but also give the feeling of openness. They are available in myriad colors to suit the style of virtually any building.
According to Siva Davuluri, director of strategic marketing at CornellCookson, for parking garages in particular, grilles are the most common option, even compared to doors. He says, “Architects, owners, and designers like the open feeling as opposed to having a dark, closed space. With many parking garages, the same grille panels are used to make fixed panels around the perimeter so it all looks similar with the same cohesive design. For security purposes, high-performance grilles help security personnel to see there is no one doing mischief. Also, high-performance grilles aid with visibility for customers, making it easier for cars to see what’s behind the opening.”
Photo courtesy of CornellCookson
The benefits of high-performance grilles include aesthetics, security, and visibility.
Cycle Counts and Why They Matter
The term cycle means one full opening and closing of a door or grille—going from fully closed, fully open, and back again. The Door & Access Systems Manufacturers Association (DASMA) definition of high-performance doors states that they must meet the 100 cycles per day mark, except that cycles of doors/grilles aren’t always spread out over the entire day. There is a significant difference in wear (and subsequently in construction requirements) for a grille that will cycle 100 times in one hour vs. one that will cycle four times each hour for 24 hours.
Figuring out the right kind of cycle life (meaning maximum cycles expected during peak periods, not just total cycles) is critical to selecting the right type of high-performance door.
Total cycles matter, but as noted, timing matters more. Let’s say you have a grille in a parking garage with 100 spots in a secure building that requires proof of clearance to enter and closes after each car passes through. There is only one way to enter, and staff that work in the building have shift times that start between 7 a.m. and 9 a.m. and end between 3 p.m. and 5 p.m. This means you’ll have 200 daily cycles, but the vast majority will be in two separate two-hour windows. Your door must be able to handle the high use in the short window of time without breaking down or wearing out.
High-Performance Construction vs. High-Cycle Springs
A true high-performance rolling grille must be built for durability from the bottom up. There is a myth circulating in the industry that springs = cycle life. If everything about your high-performance grille is the same as a standard grille, but you put high-cycle springs on it, you have a high-cycle-spring grille—not a high-performance grille. In fact, the gold standard for high-performance rolling closures is actually a springless design. Springs inevitably break and need to be replaced, causing downtime and maintenance fees.
So, what else needs to be built for high performance? The operator system, for one, needs to be able to handle the maximum number of cycles in the minimum amount of time you expect to use it. A direct drive operator is a good investment, as there are no chains or sprockets to wear out. And it should feature a soft start and stop to increase life by reducing wear and tear. On open, the speed of a best-in-class, high-performance rollup grille should start opening at a slow speed, ramp up in the middle, and then slow down before reaching the fully open position. The reason is to reduce wear and tear on all door components, but especially the operator. The guides (metal channels that hold the curtain in) also need to be robust enough to handle frequent fast operation. Experts recommend looking for self-lubricating guides to prolong curtain life.
Choosing Materials for Design and Functionality
The fenestration materials that you choose matter to the design, function, and longevity of your building—whether it’s withstanding weather or replicating the details of historic design. Choosing the right material for windows and doors is an important but sometimes confusing decision—the core structural composition, interior material, and exterior cladding all contribute to appearance and performance.
It is recommended to look for a manufacturer where experts regularly assess each material and adjust selection, testing, and design accordingly in an effort to make durable and high-performing products.
Among the most popular window and door materials in the marketplace—each offering unique benefits and advantages for homeowners, builders, and architects—are the following:
- Wood is a premium material for windows and doors, offering classic aesthetic appeal, many options for customization, and design versatility, creating a warm, natural feeling within contemporary spaces and historic buildings alike. Also, it handles various treatments and finishes well. Unlike other materials, wood has an inherent richness due to it being a natural material—no two pieces are exactly alike.
As a material, wood offers many benefits. It maintains its properties throughout drastic temperature changes. It also provides exceptional insulation. And it is a renewable material that also requires very little energy in the production of an end product, making wood an environmentally friendly option.
According to Ben Wallace, materials science manager at Marvin Windows and Doors, one caveat with wood is that if wood has too much moisture, it is more vulnerable to warping and unable to accept preservatives, paints, or stains. He recommends making sure the manufacturer confirms that suppliers are consistently grading lumber and providing the moisture content required. He adds, “To be sure that the wood has the right percentage of moisture content, the manufacturer should take an extra step once they receive it from suppliers, running cut lumber through machines that measure its moisture content. If the moisture content does not fall within the acceptable 6 to 12 percent range, the machine should separate the unsatisfactory lumber from the rest of the wood. This attention to wood throughout the supply chain contributes to quality craftsmanship, as well as longevity and performance of products over time.”
Photo courtesy of Marvin Windows and Doors
Wood is among the most popular window and door materials in the marketplace, offering environmental benefits, excellent insulation, and classic aesthetics, as well as many options for customization and design versatility.
- Extruded aluminum is an extremely tough cladding that protects wood windows. This results in superior durability for the major clad components of typical fenestration products —frame, sash, casing, and divided lites.
Thin aluminum, however, can dent easily, causing headaches for homeowners and builders alike. To provide protection and strength, experts recommend looking for extruded aluminum that exceeds industry standards, thereby elevating exterior cladding to a new level of performance.
Some manufacturers’ extruded aluminum meets the highest American Architectural Manufacturers Association (AAMA) 2605 standard, which requires 10 years of color retention and chalk resistance. An extruded aluminum substrate with an extremely tough surface coating will result in significantly superior surfaces on major clad components.
Unlike rollform aluminum, high-quality extruded aluminum profiles are formed first, then painted, which results in superior adhesion and a consistently uniform finish. The AAMA 2605 standard for rollform aluminum components requires only a 0.9-millimeter finish thickness, instead of the 25 percent thicker 1.2-millimeter coating required to meet the AAMA 2605 standard for extruded aluminum. This means that the extra finish provides increased protection, thickness, and durability, ensuring that clad products meeting these specifications will retain their color, gloss, and beauty for years to come.
- Pultruded fiberglass, an innovative material that is highly durable, as strong as steel, extremely reliable, and can perform as well years after installation as it does on day one—requiring little maintenance.
Composite materials used by different manufacturers will vary. Experts recommend thermoset composite materials rather than thermoplastic. When the material makeup contains a high density of woven fibers bound by a thermally set resin, it will make the product more resistant to pressure and temperature than thermoplastic composites. Thermosets, in fact, will hold their shape up to 285 degrees Fahrenheit. This means that windows using this type of composite will maintain their shape—even in harsh climates with regular exposure to temperature variation.
Opening Glass Wall Systems
For manufacturers, it’s important to supply products that enable the architect to fulfill their vision while also providing a product that lasts. These points are as important to the architect as the aesthetic—as well as the product being recommended to the client. In other words, you want to be able to trust the product within your design to fulfill the objective but to also not let you down. An example of such a product is opening glass wall systems, which can be customizable.
Design and Performance
According to Matt Thomas, marketing manager for NanaWall Systems Inc., “Large openings are easy to design, but it’s the performance when closed that matters most. Glass walls must perform during all seasons of the year—especially glass walls that open. Their performance is critical.” In fact, the true measure of quality is how an opening glass wall performs when closed. This is the most important attribute, as it’s potentially the weakest link if not designed correctly. Performance attributes to look for may include:
- Energy efficient: When the opening glass wall system is closed, the energy-efficient design should keep the cold on the outside while maintaining warmth inside—even right up against the glass and frames.
- Seals out wind and rain: Specialized seals and panel design can provide superior humidity and moisture control, while sill designs can resist wind-driven water from entering the home.
- Extreme weather resistance: When closed, the glass walls should form a refuge against extreme weather, keeping occupants comfortable and secure. Some manufacturers’ products include moving structural posts that provide unparalleled strength in a Miami-Dade County and AAMA hurricane approved (NOA 15-0226.05 and 15-226.06) system.
Photo courtesy of Nanawall Systems
Opening glass wall systems provide both beauty and function for a variety of applications. Shown here is Skullcandy headquarters in Salt Lake City.
Watch the video clip below to see an opening glass wall system in action.
Slim Glass Systems
Structurally glazed, operable walls with minimal sightlines is a growing trend in the industry. More and more people are becoming aware of the benefits from both aesthetic and performance perspectives.
Architects tend to question how the profiles of this type of system are so thin (less than 1 inch), but manufacturers rely on the structural glazing rather than the frame for support. This also allows for the panels to be larger, so that occupants can enjoy an expansive, uninterrupted view.
“Twenty-five years ago, Swiss engineers at a leading fenestration manufacturing company modified the function of glazing to invent a sliding system with ultra slim sightlines,” explains Jessica Kim, senior technical marketing manager at Vitrocsa USA. “In its traditional role, glass fills the frame and performs virtually no static function. It was found that glass can be used as a structural element that itself supports the window, resulting in a minimal frame that serves simply as the guide along which the glass can slide. The invisible sliding glass wall was invented.”
Features of Slim Glass Systems
Sliding systems are available with both horizontal and vertical profiles, but slim glass systems can also be fixed, or there can be pivoting systems with the same slim and matching profiles. Regardless, stainless-steel roller bearings are in the tracks, which allows for the panels to span from the floor to the ceiling. Some of these systems are even self-draining, meaning water and debris can flow through the tracks without interrupting the operation of the system.
Photo courtesy of Vitrocsa USA
Eighteen-foot oversized sliders have been installed at St. Patrick’s Cathedral. The aluminum is clad in bronze to match the surroundings.
Design Features
- Maintain consistent slim sightline throughout all product offerings
- Slim profile allows zero visual boundaries between the inside and outside of building; brings the outdoors in
Performance
- The units are generally dual glazed or triple glazed
- Thermally broken
- NFRC rated
- Air and water tightness tested
- Acoustic rated
- Able to withstand harsh climates
Historic Renovations
Specialty manufacturers can play a key role in helping owners and developers meet stringent historic renovation requirements with innovative solutions, including replication windows. Architects frequently seek a design that has not previously been manufactured. Architectural product manufacturers that specialize in custom solutions will work closely with them to create a new design to meet their exact needs.
Product options may include not only custom designs to satisfy project needs but also creation of an entirely new product, such as a new steel replication window for the Starrett Lehigh Building in New York City.
Benefits of Using Modern Materials and Designs
Retrofitting older buildings with modern materials and designs provides higher structural performance and thermal efficiency. Historic window products can offer a wide range of aesthetic options that transform historic buildings into modern performing buildings while retaining their original appearance.
Photo courtesy of Graham Architectural Products
The Starrett Lehigh Building retrofit in New York City features a new steel replication window for the landmark structure.
Conclusion
Designers and architects looking to meet a host of challenges related to building openings have an enormous advantage given the current options available to them. From aesthetics and design trends to code compliance and energy efficiency, innovations in fenestration play an integral role in helping to optimize the aesthetics and performance of new construction and renovation projects throughout the United States and beyond.
