Photo courtesy of Inpro
Windows with operable shading devices can take advantage of daylighting while protecting occupants from unwanted glare and heat gain.
Sustainable design starts with the choices architects make—everything from materials to technology impacts a building’s durability, energy efficiency, and overall carbon footprint. One of the best ways to build sustainably is to retrofit existing structures instead of starting from scratch. Building reuse cuts down on waste, saves energy, and uses fewer raw materials, especially when demolition is involved. This article explores the overall sustainability benefits of retrofitting existing projects compared with building new. It also stresses the importance of specifying building materials that support sustainability goals and environmentally positive outcomes. Using case studies and real-world examples, this article considers the impact of specifying building products and materials in both new and retrofit projects that support durability, ease of maintenance, and cleanability, while promoting a healthier environment that supports occupants’ safety and welfare.
DURABILITY AS AN ASPECT OF SUSTAINABILITY
Durability is a critical component of sustainable design. To be sustainable, a project must be designed and specified to withstand external stresses and shocks, as well as regular use from occupants.
Durability includes how the building performs over time; it is directly tied to resilience, which can be defined as a building’s ability to withstand and recover from regular stressors and shocks. Durability of the building as a whole also depends on the durability of individual systems and materials, and how they work within systems, as part of a wall or building envelope, for instance.
Flexibility is another aspect of durability. Buildings must be flexible enough to perform to today’s standards and be capable of upgrades in the future as technology and performance expectations change. A building that can be modified to accommodate future uses or even be adapted to a different use will remain in service longer than one that cannot. Here, aesthetics are a consideration. Though classic, time-honored materials and design modalities are more likely to endure than trendy ones, architects and designers should anticipate that preferences will change and create designs that allow for cosmetic changes without damaging the underlying structure.
Sustainable From the Outside In
Truly sustainable designs promote building durability as part of a complete design philosophy. Durable buildings inherently last longer, extend the lifespan of projects, and avoid early replacement. These attributes ultimately mean that fewer natural resources are expended, less energy is used to manufacture, less material is in the waste stream, and a better economic return on investment for building owners.
Site orientation that improves daylighting; a structure that resists seismic forces; a building envelope design that addresses water intrusion, uncontrolled air movement, and seismic forces—all of these are components of durability that impact the health, safety, and welfare of occupants and must be considered through both creative design elements and the specification process.
Designing for site and climate: Designing for durability requires a holistic and integrated approach that considers the hazards and vulnerabilities—and opportunities—of a particular site and climate. Some of the potential hazards include earthquakes, tornadoes, hurricanes, high-wind events, flooding, and wildfires. It’s also important to understand the climate and how weather patterns may be changing. For instance, is the region experiencing more frequent and intense heat waves or winter storms? Other site-specific considerations include the terrain and how it interacts with prevailing winds, along with how the building can take advantage of the solar resource and shading. Finally, site design should consider the connections between the building and existing communities and infrastructure, and services.
A more durable and sustainable design will seek to protect the building (and its occupants) from hazards while working with natural resources of the site—for example, a passive solar design with high-performance windows and operable shading devices uses daylighting and heat gain to its advantage while protecting occupants from overheating and glare. Such a design accrues multiple benefits—reduced energy use, along with a more pleasant and comfortable interior environment, for example.
Sound structure: The structural components of a building—its foundation, columns, beams, walls, and floors—must support all loads for the life of the building. Commonly used structural materials like steel and concrete have high embodied carbon; therefore, it’s important to ensure that structural systems are strong and durable and will survive shocks with minimal damage, yet not over-engineered, using more materials than necessary.
A high-performance building envelope: The building envelope is the first line of defense against the elements, including wind, water (liquid and vapor), air, and temperature extremes. The envelope should be designed with high-quality, durable materials, but the building’s location will influence specific choices; for instance, fiber cement or stucco cladding and metal roofing are good choices for projects in zones at high risk for wildfires.
A durable envelope that’s well designed and properly installed supports sustainability while conferring other benefits to occupants. A high-performance building envelope reduces energy consumption; it also buffers occupants from temperature extremes, ensuring a safe, comfortable environment during these events. Such an envelope will manage moisture so that it does not accumulate and harbor mold, which can result in poor indoor air quality.
Good moisture management will also ensure components of the building are not subject to rot or corrosion, ensuring their performance for the life of the building.
Interior stresses: Many interior building elements are subject to wear and tear. This is especially true of institutional buildings like schools and healthcare facilities. Utilizing durable materials for exposed and high-traffic areas—floors, walls, corners, for example—can enhance sustainability by minimizing the frequency of replacements, conserving resources, and reducing environmental impact over the building’s lifecycle. Ease of maintenance is an important consideration here, as these surfaces must be cleaned frequently to ensure a safe, healthy environment.
Photo courtesy of Inpro
Carpet tiles may wear more quickly in high-traffic areas, but they can be replaced without replacing the entire flooring system.
DESIGNING FOR THE CIRCULAR ECONOMY
Unfortunately, many contemporary buildings have been designed with only short-term goals in mind. Too often, it is assumed that buildings will have a limited lifespan, only to be torn down and replaced with something better. The AIA, in its Framework for Design Excellence2, rightly criticizes this status quo as “inefficient, wasteful, and [one that] squanders the earth’s finite natural resources.”
Currently, construction and demolition debris are huge components of global waste. By contrast, “recycled and recyclable buildings and building materials are key components of a circular economy.” A circular economy is one where buildings and products are designed for long life and reused; where products and materials are continuously reused, refurbished, and recycled; and where waste is avoided at all costs.
No one can predict the future, but it is possible to anticipate a time when a particular building will no longer serve its current client. To preserve limited natural resources, reduce waste and carbon emissions, it’s essential to start thinking of buildings as material repositories that temporarily store resources, even if for decades. This approach requires designing systems that can be easily dismantled and reused. One example is structural systems that serve as finish materials—exposed cross-laminated timber elements, for example. Finishes that enable replacement of one damaged or worn area without replacing the entire system are another example of this approach: carpet tiles in high-traffic areas that can be individually replaced, or wall protection that is attached with mechanical fasteners rather than adhesives.
A holistic approach to materials vetting: You are likely starting to see that good design, which includes careful product specification, has significant impacts on many aspects of sustainability, including durability, embodied carbon, energy performance, and the occupant experience. Material selection is one of an architect’s top—and most onerous—responsibilities. Architects are tasked with many layered criteria—aesthetics and cost, chief among them. Layered on these requirements are the many aspects of sustainability and performance, including energy efficiency, embodied carbon, impacts on human health and the environment, and durability.
Increasingly, architects and specifiers are embracing a holistic approach to material vetting. This approach is perhaps best expressed in the AIA Materials Pledge where human, social equity, ecosystem and climate health and a circular economy are all supported.
Considering and balancing all of these requirements can be daunting. Third-party documentation and certifications can help vet materials for these holistic impacts. An important first step is learning what “ingredients” different building products contain. For help, look for third-party documentation such as environmental product declarations (EPDs) and health product declarations (HPDs), as well as documentation verifying that products have been tested through standardized durability tests.
Cultivating relationships with manufacturers committed to transparency and sustainability is key; preferring these manufacturers will help move the entire industry in a more sustainable direction. Look for manufacturers that offer products made from recycled content, host internal take-back programs, and commit to reducing carbon emissions, water, and waste.
THE BENEFITS OF RETROFIT OVER NEW CONSTRUCTION
The United States is home to a staggering number of existing buildings, including nearly 6 million commercial structures.⁴ Every year, some 200,000 to 300,000 existing buildings are demolished.5 Many of the buildings that are slated for demolition today are being replaced because they lack adequate water mitigation systems, insulation, weatherproofing, and ventilation. Older buildings may also be vulnerable to rot and deterioration because of poor building envelope design or improper installation. While new constructions must adhere to today’s stricter building and energy codes, existing buildings are, by comparison, less efficient, less safe, and less comfortable. These buildings represent a tremendous opportunity.
Reusing and updating an existing building is one of the most impactful sustainability decisions a firm or client can make. First of all, retrofitting rather than building new can drastically reduce the natural resources used in a project. Retrofits can potentially lower the building’s overall embodied carbon footprint, especially if existing concrete foundations and steel framing are retained.
Though it requires an evolution in approach, designing buildings for reuse and disassembly is essential if we are to meet collective goals for reducing carbon emissions, preserving natural resources and biodiversity, and reducing waste and other negative impacts on communities and the environment. Here are some of the opportunities architects, designers, and owners should consider when weighing a renovation over a new build:
Improved energy efficiency: Retrofitting an existing building to meet or exceed current energy codes will reduce an existing building’s energy consumption, lower energy bills for the owner or client, and likely make it more comfortable for occupants, too. Strategies include upgrading HVAC systems, replacing windows, and adding or enhancing insulation to roofs, walls, and floors. Renewable energy systems such as solar arrays may also be incorporated, and can potentially help achieve the goal of net-zero energy use.
It’s important to address the performance of the building envelope itself when upgrading HVAC systems. This includes testing and addressing places where air and moisture can infiltrate.
Improved resilience: Climate change is affecting how new buildings are designed. Resilience, or the ability to withstand and recover from shocks and stressors, is increasingly important. Resilience should be a key consideration for retrofits, too. In the time since an existing building was constructed, weather patterns and average temperatures may have changed; the region may also be experiencing more extreme weather events such as floods and wind storms. Retrofitting offers an opportunity to make the building more resilient to these stressors.
Structural systems may be strengthened or enhanced to boost resistance to seismic forces and wind. Ways to accomplish this include reinforcing beams, columns, and foundations; adding shear walls to boost lateral stability; adding expansion joints; and retrofitting roofs so they can withstand greater wind loads.
Another way to boost resilience is by adding redundant and backup systems—a solar array with storage batteries and/or a generator, for example.
Enhanced occupant health, safety, and well-being: Older buildings often lack adequate ventilation and access to fresh air and natural light. These buildings may expose occupants to poor indoor environmental quality, or IEQ. Inadequate ventilation or poor envelope design can create problems with moisture intrusion and humidity levels, which may promote mold growth. A retrofit offers an excellent opportunity to remedy these issues; it’s also a good time to enhance accessibility, egress, wayfinding, and fire performance.
Enhanced biophilic connections: Buildings allow occupants to learn, work, and play in a protected and comfortable indoor environment; however, they can also connect people with views of nature, natural light, fresh air, and even natural materials such as wood and stone. Notably, many existing buildings were designed before the full range of these benefits was understood. Retrofitting offers an opportunity to incorporate biophilic design elements such as daylighting, natural materials, and patterns and images inspired by nature.
Photo courtesy of Inpro
Warm wood, curving lines, and brightly colored abstract leaves contribute to a well-integrated biophilic design in this setting.
Photo courtesy of Inpro
Windows with operable shading devices can take advantage of daylighting while protecting occupants from unwanted glare and heat gain.
Sustainable design starts with the choices architects make—everything from materials to technology impacts a building’s durability, energy efficiency, and overall carbon footprint. One of the best ways to build sustainably is to retrofit existing structures instead of starting from scratch. Building reuse cuts down on waste, saves energy, and uses fewer raw materials, especially when demolition is involved. This article explores the overall sustainability benefits of retrofitting existing projects compared with building new. It also stresses the importance of specifying building materials that support sustainability goals and environmentally positive outcomes. Using case studies and real-world examples, this article considers the impact of specifying building products and materials in both new and retrofit projects that support durability, ease of maintenance, and cleanability, while promoting a healthier environment that supports occupants’ safety and welfare.
DURABILITY AS AN ASPECT OF SUSTAINABILITY
Durability is a critical component of sustainable design. To be sustainable, a project must be designed and specified to withstand external stresses and shocks, as well as regular use from occupants.
Durability includes how the building performs over time; it is directly tied to resilience, which can be defined as a building’s ability to withstand and recover from regular stressors and shocks. Durability of the building as a whole also depends on the durability of individual systems and materials, and how they work within systems, as part of a wall or building envelope, for instance.
Flexibility is another aspect of durability. Buildings must be flexible enough to perform to today’s standards and be capable of upgrades in the future as technology and performance expectations change. A building that can be modified to accommodate future uses or even be adapted to a different use will remain in service longer than one that cannot. Here, aesthetics are a consideration. Though classic, time-honored materials and design modalities are more likely to endure than trendy ones, architects and designers should anticipate that preferences will change and create designs that allow for cosmetic changes without damaging the underlying structure.
Sustainable From the Outside In
Truly sustainable designs promote building durability as part of a complete design philosophy. Durable buildings inherently last longer, extend the lifespan of projects, and avoid early replacement. These attributes ultimately mean that fewer natural resources are expended, less energy is used to manufacture, less material is in the waste stream, and a better economic return on investment for building owners.
Site orientation that improves daylighting; a structure that resists seismic forces; a building envelope design that addresses water intrusion, uncontrolled air movement, and seismic forces—all of these are components of durability that impact the health, safety, and welfare of occupants and must be considered through both creative design elements and the specification process.
Designing for site and climate: Designing for durability requires a holistic and integrated approach that considers the hazards and vulnerabilities—and opportunities—of a particular site and climate. Some of the potential hazards include earthquakes, tornadoes, hurricanes, high-wind events, flooding, and wildfires. It’s also important to understand the climate and how weather patterns may be changing. For instance, is the region experiencing more frequent and intense heat waves or winter storms? Other site-specific considerations include the terrain and how it interacts with prevailing winds, along with how the building can take advantage of the solar resource and shading. Finally, site design should consider the connections between the building and existing communities and infrastructure, and services.
A more durable and sustainable design will seek to protect the building (and its occupants) from hazards while working with natural resources of the site—for example, a passive solar design with high-performance windows and operable shading devices uses daylighting and heat gain to its advantage while protecting occupants from overheating and glare. Such a design accrues multiple benefits—reduced energy use, along with a more pleasant and comfortable interior environment, for example.
Sound structure: The structural components of a building—its foundation, columns, beams, walls, and floors—must support all loads for the life of the building. Commonly used structural materials like steel and concrete have high embodied carbon; therefore, it’s important to ensure that structural systems are strong and durable and will survive shocks with minimal damage, yet not over-engineered, using more materials than necessary.
A high-performance building envelope: The building envelope is the first line of defense against the elements, including wind, water (liquid and vapor), air, and temperature extremes. The envelope should be designed with high-quality, durable materials, but the building’s location will influence specific choices; for instance, fiber cement or stucco cladding and metal roofing are good choices for projects in zones at high risk for wildfires.
A durable envelope that’s well designed and properly installed supports sustainability while conferring other benefits to occupants. A high-performance building envelope reduces energy consumption; it also buffers occupants from temperature extremes, ensuring a safe, comfortable environment during these events. Such an envelope will manage moisture so that it does not accumulate and harbor mold, which can result in poor indoor air quality.
Good moisture management will also ensure components of the building are not subject to rot or corrosion, ensuring their performance for the life of the building.
Interior stresses: Many interior building elements are subject to wear and tear. This is especially true of institutional buildings like schools and healthcare facilities. Utilizing durable materials for exposed and high-traffic areas—floors, walls, corners, for example—can enhance sustainability by minimizing the frequency of replacements, conserving resources, and reducing environmental impact over the building’s lifecycle. Ease of maintenance is an important consideration here, as these surfaces must be cleaned frequently to ensure a safe, healthy environment.
Photo courtesy of Inpro
Carpet tiles may wear more quickly in high-traffic areas, but they can be replaced without replacing the entire flooring system.
DESIGNING FOR THE CIRCULAR ECONOMY
Unfortunately, many contemporary buildings have been designed with only short-term goals in mind. Too often, it is assumed that buildings will have a limited lifespan, only to be torn down and replaced with something better. The AIA, in its Framework for Design Excellence2, rightly criticizes this status quo as “inefficient, wasteful, and [one that] squanders the earth’s finite natural resources.”
Currently, construction and demolition debris are huge components of global waste. By contrast, “recycled and recyclable buildings and building materials are key components of a circular economy.” A circular economy is one where buildings and products are designed for long life and reused; where products and materials are continuously reused, refurbished, and recycled; and where waste is avoided at all costs.
No one can predict the future, but it is possible to anticipate a time when a particular building will no longer serve its current client. To preserve limited natural resources, reduce waste and carbon emissions, it’s essential to start thinking of buildings as material repositories that temporarily store resources, even if for decades. This approach requires designing systems that can be easily dismantled and reused. One example is structural systems that serve as finish materials—exposed cross-laminated timber elements, for example. Finishes that enable replacement of one damaged or worn area without replacing the entire system are another example of this approach: carpet tiles in high-traffic areas that can be individually replaced, or wall protection that is attached with mechanical fasteners rather than adhesives.
A holistic approach to materials vetting: You are likely starting to see that good design, which includes careful product specification, has significant impacts on many aspects of sustainability, including durability, embodied carbon, energy performance, and the occupant experience. Material selection is one of an architect’s top—and most onerous—responsibilities. Architects are tasked with many layered criteria—aesthetics and cost, chief among them. Layered on these requirements are the many aspects of sustainability and performance, including energy efficiency, embodied carbon, impacts on human health and the environment, and durability.
Increasingly, architects and specifiers are embracing a holistic approach to material vetting. This approach is perhaps best expressed in the AIA Materials Pledge where human, social equity, ecosystem and climate health and a circular economy are all supported.
Considering and balancing all of these requirements can be daunting. Third-party documentation and certifications can help vet materials for these holistic impacts. An important first step is learning what “ingredients” different building products contain. For help, look for third-party documentation such as environmental product declarations (EPDs) and health product declarations (HPDs), as well as documentation verifying that products have been tested through standardized durability tests.
Cultivating relationships with manufacturers committed to transparency and sustainability is key; preferring these manufacturers will help move the entire industry in a more sustainable direction. Look for manufacturers that offer products made from recycled content, host internal take-back programs, and commit to reducing carbon emissions, water, and waste.
THE BENEFITS OF RETROFIT OVER NEW CONSTRUCTION
The United States is home to a staggering number of existing buildings, including nearly 6 million commercial structures.⁴ Every year, some 200,000 to 300,000 existing buildings are demolished.5 Many of the buildings that are slated for demolition today are being replaced because they lack adequate water mitigation systems, insulation, weatherproofing, and ventilation. Older buildings may also be vulnerable to rot and deterioration because of poor building envelope design or improper installation. While new constructions must adhere to today’s stricter building and energy codes, existing buildings are, by comparison, less efficient, less safe, and less comfortable. These buildings represent a tremendous opportunity.
Reusing and updating an existing building is one of the most impactful sustainability decisions a firm or client can make. First of all, retrofitting rather than building new can drastically reduce the natural resources used in a project. Retrofits can potentially lower the building’s overall embodied carbon footprint, especially if existing concrete foundations and steel framing are retained.
Though it requires an evolution in approach, designing buildings for reuse and disassembly is essential if we are to meet collective goals for reducing carbon emissions, preserving natural resources and biodiversity, and reducing waste and other negative impacts on communities and the environment. Here are some of the opportunities architects, designers, and owners should consider when weighing a renovation over a new build:
Improved energy efficiency: Retrofitting an existing building to meet or exceed current energy codes will reduce an existing building’s energy consumption, lower energy bills for the owner or client, and likely make it more comfortable for occupants, too. Strategies include upgrading HVAC systems, replacing windows, and adding or enhancing insulation to roofs, walls, and floors. Renewable energy systems such as solar arrays may also be incorporated, and can potentially help achieve the goal of net-zero energy use.
It’s important to address the performance of the building envelope itself when upgrading HVAC systems. This includes testing and addressing places where air and moisture can infiltrate.
Improved resilience: Climate change is affecting how new buildings are designed. Resilience, or the ability to withstand and recover from shocks and stressors, is increasingly important. Resilience should be a key consideration for retrofits, too. In the time since an existing building was constructed, weather patterns and average temperatures may have changed; the region may also be experiencing more extreme weather events such as floods and wind storms. Retrofitting offers an opportunity to make the building more resilient to these stressors.
Structural systems may be strengthened or enhanced to boost resistance to seismic forces and wind. Ways to accomplish this include reinforcing beams, columns, and foundations; adding shear walls to boost lateral stability; adding expansion joints; and retrofitting roofs so they can withstand greater wind loads.
Another way to boost resilience is by adding redundant and backup systems—a solar array with storage batteries and/or a generator, for example.
Enhanced occupant health, safety, and well-being: Older buildings often lack adequate ventilation and access to fresh air and natural light. These buildings may expose occupants to poor indoor environmental quality, or IEQ. Inadequate ventilation or poor envelope design can create problems with moisture intrusion and humidity levels, which may promote mold growth. A retrofit offers an excellent opportunity to remedy these issues; it’s also a good time to enhance accessibility, egress, wayfinding, and fire performance.
Enhanced biophilic connections: Buildings allow occupants to learn, work, and play in a protected and comfortable indoor environment; however, they can also connect people with views of nature, natural light, fresh air, and even natural materials such as wood and stone. Notably, many existing buildings were designed before the full range of these benefits was understood. Retrofitting offers an opportunity to incorporate biophilic design elements such as daylighting, natural materials, and patterns and images inspired by nature.
Photo courtesy of Inpro
Warm wood, curving lines, and brightly colored abstract leaves contribute to a well-integrated biophilic design in this setting.
Retrofit Design Considerations, Inside and Out
Material selection for retrofits differs from new construction in a few key ways. Depending on the extent of the retrofit, the changes may range from replacement of entire systems to mostly cosmetic changes; for example, flooring, wall paneling, and acoustic treatments may be updated, along with furnishings, signage, and accessories like window shades and drapes.
In any case, durability should be a top consideration. Specifying durable materials contributes to the project’s sustainability by minimizing the frequency of replacements, conserving resources, and reducing environmental impact over the building’s lifecycle.
“It’s extremely important to consider the durability of products when it comes to sustainable design because using less material is a key cornerstone to sustainability – think “REDUCE, reuse, recycle,” in that order,” says Jessica Jenkins, Inpro Environmental & Technical Project Specialist. “A product that lasts 10 years is much more sustainable than one that needs to be replaced frequently – even if the frequently replaced product looks better on paper for environmental performance.”
A tool called life cycle analysis, or LCA, can help specifiers evaluate options and make informed decisions. Such an analysis calculates the environmental impact of a building, system or single product or material over its entire lifetime. Durable products may have a lower lifetime environmental impact because they last longer; flooring that lasts decades is a more sustainable choice than cheap carpeting that has to be replaced every three to five years, for example. An LCA can also reveal that products with a higher initial cost may cost less over the lifetime of the building, as they may need to be replaced less frequently and require lower maintenance.
As seen in the previous section, EPDs, HPDs, and third-party certifications such as Declare, GREENGUARD, and others can also help specifiers evaluate products using a holistic set of sustainability criteria. The following examples illustrate how careful specification of durable products can ensure retrofit projects meet performance, comfort, and sustainability goals.
Example 1: A Healthcare corporate office upgrade: Adding or replacing existing glazing with high-performance windows is a key part of a building retrofit design that can significantly improve energy efficiency, daylighting, aesthetics, acoustic performance, and more. Windows are also part of a successful biophilic design strategy, connecting occupants with views of nature, natural light, and even fresh air; however, it’s important to anticipate and mitigate potential drawbacks such as glare, UV damage, and unwanted heat gain.
Window treatments can work hand in hand with energy-efficient windows to provide the benefits of natural light and solar gain while protecting occupants from these unwanted consequences. For example, solar shades are made with a material that lets in daylight while blocking UV light and heat. Some shades are available in natural patterns and colors, helping to create a soothing, pleasant indoor environment.
An office retrofit shows how window treatments can be used to achieve energy efficiency and daylighting goals while creating a productive and appealing work environment. Here, a former insurance company office was retrofitted to serve as a corporate office for a nonprofit healthcare network. The design retained the original tall, narrow window openings but used window treatments to balance the benefits of natural light with privacy and protection from UV damage and glare. The design utilizes a combination of motorized drapery, solar shades, and mini aluminum blinds.
Example 2: Expansion joint systems bolster iconic public building: Many existing buildings were designed before seismic requirements were enacted or upgraded. However, in many cases it is feasible—and desirable—to perform a seismic retrofit and preserve the building. Such retrofits strengthen load-bearing components and their connections to each other and to the building’s foundation. The retrofitted building is better able to resist shaking forces and is less likely to suffer damage during an event—and better able to protect building occupants.
A key strategy in a seismic retrofit is the installation of expansion joints. These strategically placed gaps, which can be installed in walls, ceilings, or floors, allow multidimensional movement of a building during storms and earthquakes. Manufacturers can design expansion joint systems to fit a structure’s particular requirements. Some manufacturers also offer expansion joint covers to create a seamless appearance.
A retrofit of the Exploratorium, an iconic exhibit space located on the San Francisco waterfront, shows how expansion joints can be used to upgrade a building’s safety and resilience while retaining its essential character and function.
Almost 1,500 linear feet of interior and exterior seismic expansion joints, which ranged in width from 8 to 27 inches, were installed throughout the building. Close to 95 percent of these were custom designed and built, including several joints that incorporate 3/8”-thick aluminum diamond plate. Because the Exploratorium is built over the water, designers specified Kynar coatings on many of the joint systems to resist corrosion from saltwater. Waterproof fire barrier was also incorporated in places.
In keeping with the Exploratorium’s engaging educational focus, a dedicated display explains the forces to which the building is subjected and explains how expansion joints help a building withstand thermal and seismic movement.
Photo courtesy of Inpro
San Francisco’s beloved Exploratorium was retrofitted to meet the state’s rigorous seismic standards.
Example 3: Wall coverings update lobby with biophilic elements: Often, a retrofit involves replacing worn or outdated finish materials such as flooring, wall protection, acoustic treatments, and elevator interiors. Again, durability is a top consideration that should be balanced with other aspects of sustainability. Here’s where manufacturer transparency is critical for comparing one product with another. For example, wall protection is typically made from vinyl. This material is widely specified because of its durability, cleanability, and price point; however, it has significant environmental impacts throughout its life cycle. At least one manufacturer offers rigid wall protection made with 100 percent recycled pre-consumer content, making this a more sustainable option.
A renovation of an administration building lobby shows how wall protection can be used to update a space and enhance it with biophilic elements. The main stairway, lobby walls, and columns of the TwinStar Credit Union building were updated with rigid sheet panels that resemble oak. The panels are paired with clear anodized aluminum trim for a warm but crisp and modern look. Wood is a timeless material that never goes out of style; in addition, these panels are easy to clean and resistant to marks and scratches, ensuring they will look new for years to come.
Photo courtesy of Inpro
Wood is a timeless and universal biophilic material. Here, panels that resemble real oak are used to refresh a commercial lobby and stairwell.
A FOCUS ON OCCUPANT SAFETY AND WELFARE
Building material and product specifications can directly impact occupant health, safety, and welfare. It’s critical that specifiers take a holistic approach to materials selection, considering health and safety impacts along with sustainability and performance attributes.
Healthcare and educational settings pose particular challenges. These facilities include areas of heavy traffic and high turnover. Safety and health concerns are critically important. In schools, large numbers of people interact with each other and their environment, creating the possibility for transmitting disease organisms. In healthcare facilities, it’s important to protect vulnerable patients from highly contagious bacterial infections such as MRSA. Designs should foster good Indoor Environmental Quality, or EIQ, in order to promote healing, learning, well-being, and cognitive performance in schools, hospitals, and long-term care facilities.
Let’s take a closer look at these criteria, along with case studies from health care and educational facilities that illustrate the importance of specification and the positive outcomes for occupants.
Indoor Environmental Quality refers to conditions inside a building that shape occupants’ experience. IEQ includes but is not limited to indoor air quality, or IAQ. It also includes the space plan or layout, access to daylight and views, acoustic experience, and the degree of control occupants have over lighting, space conditioning, and other aspects of their environment.
Indoor Air Quality: One important indicator of indoor air quality is the presence of volatile organic compounds, or VOCs. These include a broad class of chemicals, some natural, some synthetic, some with the potential to affect human health or comfort. Some VOCs are irritants that can cause runny nose, watery eyes, and respiratory symptoms. In the long term, exposure to VOCs may cause damage to the liver, kidneys, and central nervous system; some are also known or suspected carcinogens.
VOCs are present in many building materials, often in the form of adhesives, sealants, paints, and other finishes. Many engineered wood products contain VOCs, as do engineered wood flooring, vinyl flooring, and carpeting. These materials can “off-gas” VOCs into interior spaces, potentially affecting occupants. According to the U.S. EPA, concentrations of many VOCs are consistently and significantly higher indoors than outside.
Specifying products that are third-party tested to have low or no VOC emissions can help ensure good IAQ. There are a number of ways to vet such products. HPDs include information about VOC emissions. Third-party certifications like UL’s GREENGUARD verify that products do not exceed certain emissions thresholds.
GREENGUARD certified products are screened for more than 15,000 VOCs known to pollute indoor air. There are three tiers of certification. GREENGUARD certified products have been verified to have a total VOC emissions rate no greater than 500 μg/m3. GREENGUARD Gold certification is more stringent, with a total VOC emission rate of 220 μg/m3. These products are appropriate for healthcare and educational facilities. Finally, products that are certified GREENGUARD Formaldehyde Free meet the standards of GREENGUARD Gold and also meet a stringent threshold for the emission of formaldehyde.
Other category-specific certifications include FloorScore for flooring and Green Label Plus for carpeting and rugs. Note that specifying low-emitting products and materials can also contribute toward LEED credits.
Acoustics: Noise levels in a space don’t just make for a more or less pleasant experience; a noisy indoor environment can aggravate stress, make it difficult to hear or communicate, and in the case of healthcare patients, compromise healing and disturb sleep. Unfortunately, hospitals have only gotten noisier, despite a growing understanding of the importance of a quiet environment. Background noise from HVAC equipment combines with punctuated sounds like breathing monitor alarms to raise decibel levels well above recommended guidelines from the World Health Organization.
Noise also affects staff in both healthcare and educational facilities, contributing to higher stress, lower cognitive performance, and anxiety and depression. Architects and designers can work with facility owners to create a more healthful acoustic environment. Mechanical systems can be designed with fans, duct sizes, discharge rates, and mitigating strategies such as vibration isolators. Interior finishes also have a significant impact on acoustics. Here are just a few considerations:Specify ceiling tiles made from glass or mineral fiber, as they effectively absorb sound.Wall panels that include fabric or other sound-absorbing materials can help reduce noise levels. Specify flooring materials like rubber and carpet that lower noise transmission from footfalls, carts, and equipment.
In addition to these common finishes, products tailored specifically for healthcare environments can be specified with acoustics in mind; for example, one manufacturer offers a bendable track and carrier for privacy curtains that produces much less noise than a grooved track.
Durability, safety, and ease of maintenance: In both educational and healthcare settings, finishes should be durable and easy to clean and maintain, and they should not promote mold growth or bacteria. MRSA, which stands for methicillin-resistant Staphylococcus aureus, is a bacterium that has developed resistance to antibiotics. It is commonly found in healthcare facilities and other buildings where large numbers of people gather and live. MRSA infections are difficult to treat, and while many cause only minor skin lesions, some can affect the heart, lungs, and blood, causing pneumonia and even death. According to the Centers for Disease Control, MRSA is responsible for more than 70,000 severe infections and 9,000 deaths per year. Disinfecting surfaces is a key strategy in preventing these infections.
Finish surfaces and other frequently touched items should be easy to clean and resistant to mold and bacteria. For example, privacy and cubicle curtains can be specified with fabrics that have been treated with silane, which thwarts bacterial growth.
Wall panels, shower tubs and surrounds, bathroom partitions, countertops, and other features can be specified using solid surface materials that are non-porous and anti-microbial. The material is easy to clean using common disinfectants; in addition, chips, and marks can be easily buffed out. It is also flexible; and some manufacturers will work with clients to create customized solutions for a particular building.
The retrofit of a large barracks at a military base in Texas7 shows how solid surface products can be used to update a facility that sees heavy use. Durability was a top consideration. In this total retrofit, the building structure was retained but the interior was completely remodeled. Solid surface wall cladding and shower walls were installed in all barracks bathrooms.
Photo courtesy of Inpro
The durable solid surface material used to retrofit showers in a large barracks facility is easy to clean and disinfect.
Biophilic design that promotes well-being: As we have seen elsewhere in this article, biophilic design connects building occupants with elements of the natural world and can have a range of benefits, from improved cognitive function and stress reduction to more effective healing. These effects are especially critical in learning and healthcare environments.
Both the design of spaces and the specification of materials and products are part of biophilic design. An office plan that ensures every employee has access to natural light (while of course protecting them from glare) is an example of biophilic design, as is the specification of carpeting with a natural pattern and organic colors, or wall coverings that feature wood grain or nature-inspired artwork.
“Positive distraction” is a term used to describe the belief that environmental features can elicit positive feelings, hold attention and interest, and, therefore, reduce stressful thoughts. A renovation of the Radiology Department at Children’s National Health System in Washington, D.C., illustrates the specification of products that support good indoor air quality while introducing elements from nature that help calm and distract pediatric patients there for cancer treatment.8 Rigid wall panels and flooring work together to create an environment bathed in soothing blues and aqua colors. The wall panels feature sea creatures and ocean plants, and interesting facts about them.
CONCLUSION
By now, it should be clear that sustainability is a complex endeavor, involving not only holistic, integrated design but informed, thoughtful selection of individual products and materials. Durability is an essential element of sustainable design, helping to ensure the performance and longevity of the building and its systems, as well as individual components. One of the most sustainable choices a design practitioner can make is to retrofit an existing building rather than new construction. Retrofits offer myriad opportunities to improve energy performance along with the resilience, structural safety, health, and comfort of a building. Thoughtful selection of durable materials can support myriad design goals of a project while enhancing the health, safety, and welfare for building occupants. From structural enhancements that improve a building’s seismic performance to durable wall coverings that provide a biophilic connection to building occupants, these choices are the key to creating truly sustainable designs.
End Notes
https://www.aia.org/resource-center/environmental-product-declaration
https://www.aia.org/design-excellence/aia-framework-design-excellence
https://www.aia.org/design-excellence/climate-action/zero-carbon/materials-pledge
https://www.eia.gov/consumption/commercial/
https://bringrecycling.org/the-future-of-adaptive-reuse/#:~:text=In%20the%20United%20States%20an,energy%20embodied%20in%20the%20structure
https://pubmed.ncbi.nlm.nih.gov/31881421/
https://www.inprocorp.com/projects-by-market/government/military-base-housing-renovation/
https://www.inprocorp.com/projects-by-market/healthcare/childrens-national-health-system/
https://cesp.gmu.edu/pvc/
Andrew A. Hunt is Vice President of Confluence Communications and specializes in writing, design, and production of articles and multimedia presentations related to sustainable design in the built environment. In addition to instructional design, writing, and project management, Andrew is an accomplished musician and voice-over actor, providing score and narration for both the entertainment and education arenas. www.confluencec.com https://www.linkedin.com/in/andrew-a-hunt-91b747/
