Driving Building Performance With Data

October 14, 2020
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This post is a collaboration between Rishika Shrivastava and Chris Hazel.

Ayers Saint Gross has long embraced sustainability as a vital component of good design and we believe the more research we perform and the more data we collect, the greater our ability to achieve ambitious sustainability goals and design more beautiful and functional buildings for our clients. We have focused our thinking about building performance into two categories: embodied carbon and operational carbon.

Embodied Carbon

We utilize Whole Building Life Cycle Assessments (WBLCA) to investigate the impact and opportunities of construction materials and products to achieve our embodied carbon reduction goals. WBLCA looks at the environmental impacts of building materials (including global warming potential) over their entire life cycle—from extraction and manufacturing through the landfill or recycling plant. 

We are calculating the embodied carbon of completed projects to identify which components or life cycle stages are the largest contributors to environmental impact, and will leverage this information to inform even stronger design processes in the future.

One project we’ve completed a WBLCA on is the Hayden Library Reinvention. By renovating existing buildings in lieu of tearing them down and constructing with new materials, we avoid the embodied carbon of new construction altogether. WBLCA was conducted to quantify how much embodied carbon was preserved by maintaining 95% of the building’s existing opaque envelope and structural system and how much additional embodied carbon was invested to make the building useful for the next 50+ years. Our analysis revealed 9000 MT of CO2e was preserved in the renovation while only another 550 MT of CO2e were spent. This example illustrates how building renovation or reuse can greatly reduce construction’s embodied carbon impact.

Structural systems and building envelopes tend to be significant sources of embodied carbon. For Semans-Griswold Environmental Hall, we found that we could substantially reduce environmental impact by focusing on the materials chosen for curtainwall systems because of aluminum’s high embodied carbon. Similarly, focusing on thermal insulation also helped us reduce embodied carbon because some types of foam insulation, including expanded polystyrene (EPS), extruded polystyrene (XPS), and polyisocyanurate or spray foam insulation, have blowing agents with massive global warming potential. Specifying insulation materials with lesser embodied carbon can be helpful in reducing impact. 

Reducing embodied carbon in construction requires collaboration between designers, builders, structural engineers, and manufacturers across the building sector. WBLCA during the various design stages can be helpful in making choices between various building structural systems, assemblies, and products. We look forward to continued engagement with our partners to reach our embodied carbon reduction goals.

Operational Carbon 

While embodied carbon has more recently come to the forefront of sustainability discussions in the AEC industry, operational carbon (which occurs during the in-use phase of a building) has been the primary focus of sustainability thinking over the last several decades. Our thinking on operational carbon has continuously evolved and we are developing in-house digital tools and processes for measuring operational carbon throughout the design process so that we can produce buildings that function better, cost less to operate, are better for our planet, and are better aligned with our clients’ sustainability goals.

To reduce operational carbon in buildings, Ayers Saint Gross has been developing a process of iterative performance analysis throughout design. From early-stage climate analysis to understand site factors such as temperature, humidity, and solar access, to whole building energy models, we rely on thoroughly tested analysis tools and robust data to predict how buildings will perform prior to starting construction.

One of our most versatile methods for understanding building performance is known as “shoebox analysis.” By taking a simple, repeating element of the building (e.g., a single structural bay), we can run quick analyses on a small area but learn a lot about a large area of the building design.

We use this type of analysis to quickly learn about holistic effects of small design changes. For example, we can create a model with a small window and a large window in a repeated office module or student housing unit and compare how the variation in window size affects daylight access, outdoor view access, solar heat gain, thermal comfort, glare potential, and expected energy usage intensity (EUI). Since these models are small, we can run analyses in a fraction of the time of larger models and extrapolate the results to how a whole building is likely to perform.

The shoebox analysis is part of a larger toolkit developed by Ayers Saint Gross to evaluate expected building performance. These tools allow us to better study occupant comfort by visualizing more analytical and sensorial aspects of a building such as daylight access and thermal comfort. These tools provide a fast, reliable way for our design teams to optimize a building, saving owners money in both first costs and operational costs.

We’re excited to continue advancing strategies toward carbon neutrality. The tools we’re leveraging to optimize embodied carbon investments and reduce operational carbon will help us in aligning the people, programs, and places we serve to champion environmental stewardship, healthy living, and positive social and economic outcomes for all.

How Signage Optimizes High-Performance Buildings

October 13, 2020
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As more high performance design methods, materials, and systems are implemented in the built environment, it’s important not to forget that we as the human occupants of buildings still play a big role in their impact. Understanding occupant activities–the way people experience and use a structure over its lifespan–is key to maximizing the long-term value of any project and is a crucial part of creating effective designs.

Thoughtful signage can inform, inspire, and ultimately bolster a building’s long-term success, ensuring that high-performance elements remain front and center for users throughout a project’s lifecycle. Ayers Saint Gross encourages interdisciplinary collaboration between our architecture and graphic design studios to create building-specific interior illustrations. Here are two examples from our portfolio that illustrate how signage can reinforce sustainable design choices and create more successful buildings.

Trippe Hall at Penn State Behrend

Penn State University has a robust sustainability mission to “comprehensively integrate sustainability into the University’s core fabric of research, teaching, outreach, and operations that will transform students, faculty, and staff into competent sustainability leaders capable of carrying out our vision for the future.” However, overall efforts can sometimes be difficult to implement at individual campuses.

For a residence hall at Penn State Behrend, sustainability signage had two major benefits: it earned LEED points via an Integrated Education Innovation Credit, and it helped align the Behrend campus’ sustainable efforts to the university’s mission. With increased mission awareness, Penn State students hopefully feel individually empowered and connected to each other by their sustainable actions. 

To highlight Trippe Hall’s high-performance elements, we designed a system of 26 unique interior signs that call attention to sustainable features throughout the building.

Of course, simply putting stats on signs is usually not enough to engage users. A didactic approach isn’t fun or memorable. So our design team created slightly cheeky copy and graphics, and used a relatively scaled-down size for the interior sustainability signage. The small, strategically placed signs are a fun discovery when a user adjusts shades in the lounge or does laundry. The interdisciplinary collaboration among our interiors, sustainability, and graphic design studios, and our in-house writing staff, resulted in a custom system that is memorable and inspires action.  

We also created a 43.5’ x 9’ vinyl wall graphic in the bike storage area, which is an exterior space in the notch of the building. The large, bright graphic provides desired lightness to the otherwise dark space as well. Included on the graphic are “stickers” that list destinations around campus and their bikeable distances, encouraging the use of bikes over vehicular travel.

Bancroft Elementary School

District of Columbia Public Schools (DCPS) modernizations target LEED Gold certification and incorporate sustainability signage. The goal of including sustainability signage is to educate students on the benefits of sustainability and encourage environmental literacy and awareness.

As a part of the renovation and addition to Bancroft Elementary, sustainability signage was included as a part of a larger custom signage and wayfinding system. Originally proposed as a six-sign system installed throughout the school, our design evolved into one large graphic in a highly visible location at a scale appropriate for an elementary school audience. While small-scale signs with an element of surprise and discovery work well for college students, elementary-age students have short attention spans and multiple signs diluted the overall message. Additionally, since Bancroft students are usually confined to grade-level corridors, chances of all the students seeing all signs were limited.

Ultimately, we designed a 12’ x 10’ graphic for wall spaces on either side of the doors leading to a playground along a main corridor. Colorful graphics and statistics combined with kid-friendly messages in English and Spanish align with the school’s bilingual curriculum.

Both Trippe Hall and Bancroft Elementary demonstrate a heartening trend toward displaying sustainability information and inspiring a building’s users to take action.

Green Week 2020: The Carrot Awards

April 23, 2020
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Since 2013, Ayers Saint Gross has hosted an annual Green Week to elevate sustainability literacy within our staff, advance high-performance designs for our clients, reflect on sustainability achievements, and plan for the year ahead. Our firm continues to energetically advance the diverse interests of our clients and communities. It feels particularly important to celebrate Green Week this year, the 50th anniversary of Earth Day.

The global scientific community agrees that preserving our way of life requires keeping global warming below 2°C. Past 2°C, climate change will accelerate and become irreversible – the planet will warm until humans can no longer survive. The scientific community has established a carbon budget of 500 GtCO2e. This is the total amount of carbon human activities can emit from this day forward and stay below 2°C. Annual CO2 emissions today are approximately 40 GtCO2 per year. If we maintain the status quo on annual carbon emissions, in about 12 years global warming will accelerate. The time to act is now and as practitioners in the built environment, we play a critical role.

The AEC industry’s discussion of sustainability has historically focused on operational carbon emissions from building operations. Keeping buildings at appropriate temperature and humidity, electric lighting, and powering our plug-in devices are responsible for approximately 30% of annual carbon emissions. Missing from this dialogue, however, has been an appreciation for the embodied carbon of the actual materials from which the built environment is constructed. Industrial activity is responsible for approximately 40% of annual carbon emissions, of which half is tied to the production of concrete, steel, and aluminum alone. Concrete, steel, and aluminum are significant components of our built work as an interdisciplinary design firm, and we need to aggressively reduce the amounts of those materials we design in developing our clients’ built environments.

This week, we’ve been hosting teleconference meetings across our organization to share information that will help us in our quest to reduce embodied and operational carbon emissions from our design portfolio 50% by 2030.

These sessions included Baltimore City’s Sustainability Director, Lisa McNeilly, highlighting the creation of the Baltimore Sustainability Plan and how it’s been implemented and tracked. The Plan is framed to lead with equity and when plans, programs, and policies are implemented at the intersection of equity, economy, and the environment, outcomes are often more relevant, impactful, and longer lasting. FSi Engineers’ Ben Roush broke down the basic concepts and principles behind net-zero buildings and spoke on lessons learned over many net-zero projects. A trio of professionals from Thornton Tomasetti – Alexandra Davis, Christopher Williams, and Paul Becker – addressed why embodied carbon matters, how to identify carbon “hot spots” in a building, whether wood is truly good, and what questions architects should be asking structural engineers from the start to influence positive change and drive progress toward the AIA 2030 Commitment’s goals.

We reflect on our AIA 2030 Commitment results, the predicted energy use intensity of our whole building projects, and the lighting power density of our interiors projects. We’ve recorded this data since 2011, which enables us to recognize and reward the most energy efficient of these projects from the previous calendar year with our annual Carrot Awards to inspire other projects to strive for greater energy efficiency.

We believe sustainable design and great design are the same. Our highest performing projects under design in 2019 illustrate strategies every project in our firm aspires to achieve.

We’re pleased to announce this year’s Carrot Award winners are the Elon University Engineering and Physics Building and the Denison University Residence Hall Renovations. Congratulations to the design teams of these projects!

Elon University, Engineering and Physics Building
Elon University, Engineering and Physics Building

In collaboration with Walter Robbs Callahan & Pierce Architects, Ayers Saint Gross is designing a new Engineering and Physics Building for Elon University that will incorporate design fabrication space, prototyping equipment, and project assembly areas for the program’s engineering students. The project will expand the engineering program’s offerings and create a campus edge that will complete the quadrangle expansion between Moseley Hall and the existing Elon Elementary School. The building is composed of two parts: a three-story building that reflects the Greek Revival style of Elon University’s campus context and a two-story wing with a more modern aesthetic. Associated outdoor spaces will support community-building.

The Denison University Residence Hall Interior Renovations refresh existing residences for primarily first year students. Smith Hall, Shorney Hall, Curtis Hall, and Crawford Hall offer double and triple room options, but had limited space for community-building. For all of the halls, the entry sequence and ground floor common areas are being upgraded to provide a more open and welcoming experience. The renovations provide necessary outside the unit social spaces for residents and meet the needs of contemporary students. The new interior lighting design will reduce lighting power density by 77%, more than three times the current AIA 2030 reduction target for interior spaces, through daylighting and LED lighting.

Be on the lookout for more sustainability-focused projects from our firm. For more on how Ayers Saint Gross approaches sustainable design, see our firm’s sustainability strategy, Take Action.

Ayers Saint Gross at Advanced Building Skins

October 24, 2019
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Sustainability is a core Ayers Saint Gross value and resiliency is a crucial aspect of this goal. With much of the research and technology looking into new construction, it is important not to forget the sustainable possibilities of existing buildings.

On October 28, we will be presenting at the Advanced Building Skins Conference in Bern, Switzerland. This conference brings together Architects, Engineers, and Building Scientists (as well as material scientists and academic researchers from technical universities around the world) to share both the latest theoretical developments in building envelope technology and real-world experience and creative solutions as these advancements are put into practice. We will be presenting on the innovative double-thermal mass skin implemented as part of the Johns Hopkins Hospital Nelson Harvey Building Exterior Over-Cladding and Interior Renovation.

For hospital buildings in particular, where there can be no loss of patient care and the building must remain occupied, maximizing existing resources is paramount. By avoiding the carbon footprint associated with demolition and site work, applying inventive design solutions to existing buildings gains not only the sustainability advantages of new technologies, but also leads to an overall improvement, a substantial cost savings for the owner, and a reduced construction schedule.

For this project, forensic and visual observations of the façade disclosed severe thermal and moisture failures with decomposed flashing and lack of insulation. Similarly, the building was constructed without allowing thermal expansion vertically or horizontally of the building envelope, so areas of the façade were structurally failing, bowing, and delaminating. Like many buildings built over the last several decades, however, the structure was still sound.

Innovative solutions using thin precast concrete panels in combination with existing masonry created a hybrid double-skin envelope. In addition to all of the environmental benefits of ensuring the resiliency of the building, the double-thermal mass wall decreases heat transfer gain/loss through the building envelope for any given season and capitalizes on the high heat capacity of concrete and masonry to delay heat flow through the envelope by an action termed thermal lag. This results in a higher performing building.

We are happy to share these advancements and real-world applications with the world, and look forward to learning all the latest developments.

Green Week 2019: The Carrot Awards

April 17, 2019
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Ayers Saint Gross hosts an internal Green Week every year to advance sustainability literacy within our staff so we can provide better high-performance designs to our clients, reflect on our sustainability achievements to date, and plan for the year ahead.

Over the course of next week, we’re sharing information we’ve learned through project (or projects’) certifications, professional certifications, and conference attendance, as well as bringing in invited guests. We’re pleased to host Dr. Christine Sheppard of the American Bird Conservancy who will be speaking to our entire firm about Bird-Friendly Building Design. Anne Greenstone from Steelcase will be teaching our Baltimore office about the Fitwel certification and office wellness, and a representative from CMTA will teach our DC office more about design considerations for net-zero buildings.

Since 2011, we have annually reported the predicted energy use intensity of our whole building projects and the lighting power density of our interiors projects using the AIA 2030 Commitment. This data allows us to recognize and reward the most energy efficient of these projects from the previous calendar year with our annual Carrot Awards to inspire other projects to strive for greater energy efficiency.

We believe sustainable design and great design are the same. Our highest performing projects under design in 2018 illustrate strategies every project in our firm aspires to achieve.

We’re pleased to announce this year’s Carrot Award winners are the Hayden Library Reinvention at Arizona State University and the Brown Advisory Bond Street Office Third Floor Tenant Improvements. Congratulations to the design teams of these projects!

Hayden Library, originally built in 1966, is representative of a design and construction era that was limited by available technology and prioritized considerations for a library differently than today’s campus conditions require. The HVAC, lighting, plumbing, and architectural upgrades included as part of the library’s reinvention result in a significantly more resource-efficient building than the existing construction. The project is predicted to have an energy demand of 55% less than baseline and will offset a portion of its electricity load with a rooftop photovoltaic array. This work would not be possible without the collaboration of an engaged client and our team at Affiliated Engineers.

The Brown Advisory Headquarters Tenant Improvements provides commercial office space in Baltimore for a privately owned investment management company. The space we designed for them reduces lighting power density by 56%, more than twice the current AIA 2030 reduction target for interior spaces, through daylighting and LED lighting.

Be on the lookout for more sustainability-focused projects from our firm. For more on how Ayers Saint Gross approaches sustainable design, see our firm’s sustainability strategy, Take Action.

Ayers Saint Gross at the University of Texas at Austin Energy Week

February 1, 2019
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If you’re in Austin this coming week, I hope you’ll join me on Tuesday, February 5 for a panel discussion on building energy efficiency.

The Future of Building Energy Efficiency: Smart Building or Building Smart?

Buildings account for 40% of energy consumption in the United States. In the growing age of ‘smart’ technologies and sustainable design, how do these market drivers influence energy usage in commercial buildings? This panel will assess current design and technology-based solutions for their energy saving capabilities in existing and new commercial buildings and project the future of the industry. Discussion will also touch on the following questions: What does ‘smart building’ look like now, and in the future? What are barriers to adoption and challenges to implement tech-based solutions? How will standards and certifications (e.g., AEGB, ASHRAE, LEED, WELL, Living Building) evolve to make way for these changes?

Presenters
Zoltan Nagy, Assistant Professor, Civil, Architectural, and Environmental Engineering, UT Austin (Moderator)
Michael Sweeney, Associate Principal, Arup
Sarah Talkington, Project Manager, Austin Energy – Commercial Green Building
Allison Wilson, Sustainability Director, Ayers Saint Gross

Details
Tuesday, February 5, 2019
10:30 – 11:30 AM
Etter-Harbin Alumni Center
2110 San Jacinto Blvd, Austin, TX 78712

Ayers Saint Gross at TCUF 2018

September 13, 2018
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If you’re in San Antonio next week, I hope you’ll join the Ayers Saint Gross team at one of our three TCUF sessions, or visit our display in the Architectural Showcase. Here’s where we’ll be.

A New Era of Sustainability Planning: From Vision to Implementation
Texas A&M’s 2018 Sustainability Master Plan integrates social equity objectives with environmental and economic efforts while balancing the need for long-term vision with action and accountability. Through nine themes that address the physical environment, social sustainability, waste management, and institutional efforts, sustainability initiatives at Texas A&M have been transformed from an environment-heavy focus to an approach that places equal emphasis on all three elements of sustainability’s triple bottom line.

Concurrent to developing the university’s Sustainability Master Plan, Texas A&M’s Department of Residence Life sought ways to evaluate its contribution to institution-wide sustainability efforts and prioritize future endeavors. The Residence Life Sustainability Master Plan seeks to advance the department’s capacity to operate sustainable facilities, support sustainable life skills education, and leverage competitive advantage in the local student housing market.

Presenters
Chareny Rydl, Director of Residence Life, Texas A&M University
Lara Hendrickson, Sustainability Operations Coordinator, Texas A&M University
Allison Wilson, Sustainability Director, Ayers Saint Gross

Details
Friday September 21, 2018
Republic C (4th Floor)
1:00PM – 2:00PM


An Instigator and Path to Crafting a Campus Plan
Campus master plans, both aspirational in vision and realistic in implementation, seek to guide the long-term physical development of institutions in alignment with their vision, mission and goals. The session will evaluate and illustrate conditions supporting the need for a campus master plan, what to incorporate into the effort and how to adopt a continuum of planning on campus.

Texas A&M University’s 2017 Campus Master Plan will serve as a case study, guiding attendees through the process of determining when a plan is needed, where to focus your efforts, what elements might be included, who to engage in the process, how the proposed transformations have impacted the campus experience and why to outline future supporting planning efforts for continuous improvement.

Attendees will develop and refine skills to critically analyze past and current planning efforts to identify potential process adjustments leading to increased planning impacts on your campus.

Presenters
Lilia Y. Gonzales, University Architect, Texas A&M University
Dana Dixon, Senior Associate, Ayers Saint Gross
Corey Rothermel, Associate, Ayers Saint Gross

Details
Friday September 21, 2018
2:10PM – 3:10 PM
Republic B (4th Floor)


Enterprise Planning: A Case for Moving Beyond a Traditional Master Plan
Differing from a traditional master plan which focuses solely on the built environment, enterprise planning touches all areas of an institution to guide strategic direction. The outcome is a shared vision which becomes the framework for policies, programs, and physical space.

Through a highly collaborative process involving hundreds of Tarrant County College stakeholders, a series of charrettes acted as the primary tool for discovery, analysis, and dialogue. The activities sought to create a collective understanding of key concepts, establish big-picture priorities, and discuss stakeholder ideas for the near term and long term. These workshops created a venue to discover and analyze challenges, craft potential solutions, and define the future, all in tandem.

The outcome was the establishment of three overarching goals and a set of eight principles that together serve as the pillars of the college’s vision and guide all areas of the institution.

Presenters
Nina Petty, Vice Chancellor for Real Estate & Facilities, Tarrant County College
Doug Lowe, President, Facility Programming and Consulting
Jack Black, Principal, Ayers Saint Gross
Corey Rothermel, Associate, Ayers Saint Gross

Details
Saturday September 22, 2018
11:15 AM – 12:15PM
Crockett C/D

WELL 101: Creating Healthy Places

July 23, 2018
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For many people in the AEC industry, sustainability is synonymous with LEED, the world’s most widely used green building rating system.

At Ayers Saint Gross, however, we define sustainability as balancing the unique needs of people and ecological systems with the economic realities inherent in each project. That definition recognizes that there are multiple ways to measure success in sustainability. It also supports the triple bottom line of people, planet, and payback, and acknowledges that LEED may not always be the most appropriate yardstick with which to measure sustainability on every project.

One of the latest green building rating systems to take the AEC industry by storm is the WELL Building Standard. WELL poses a people-centric, rather than planet-centric, question: How can a building support better health, happiness, and well-being for its occupants?

I was inspired to become the first WELL AP at Ayers Saint Gross, earning my certification in June 2018, because we often design buildings for the education of health care professionals, such as our recently completed Howard Community College Science, Engineering, and Technology Building and the University of Pikeville Health Professions Education Building. It’s important to me that these projects more directly support occupants’ well-being and put the environmental factors that influence health outcomes on display. The WELL system was developed over a six-year period and formally launched in October 2014. Now administered by GBCI, WELL provides a pathway for measuring, certifying, and monitoring how buildings support human health and well-being.

Every WELL Precondition or Optimization is substantiated by medical, scientific, or industry research to ensure a data-driven system. WELL also requires ongoing monitoring, annual reporting for some features, and re-certification every three years.

This level of rigor ensures that a building doesn’t just operate as intended on day one, but that it continues to do so on day 1,001 and beyond. It’s an exciting prospect to move beyond how buildings are predicted or intended to function, and to talk about how they do function on an ongoing basis.

The WELL Building Standard v1 sorts its 105 Preconditions and Optimizations into seven concepts: air, water, nourishment, light, fitness, comfort, and mind. Below are more details on these concepts, and some suggestions for how designers and clients can thoughtfully approach the WELL certification process.

  • Air. This concept aims to optimize indoor air quality through the minimization of introduced contaminants, as well as filtration and testing to ensure air quality is conserved throughout occupancy. High indoor air quality has been linked to improved cognitive function, so it makes sense that this concept is the most heavily weighted subject within WELL.
  • Water. The water concept aims to ensure easy access to potable water and to maintain stringent standards regarding inorganic, organic, and agricultural contaminants in water for human consumption. To meet Preconditions and Optimizations, WELL projects incorporate a variety of filtration systems to ensure the purity of water for human consumption.
  • Nourishment. This is my favorite WELL concept because even without owning a commercial or institutional building, there are requirements in here that can change how I go grocery shopping and help me improve my health. Among other standards for projects that provide food service each day (including vending machines), processed foods are held to sugar restrictions and dinnerware must be within prescribed size limits to support portion control.
  • Light. The light concept addresses access to daylight and views, as well as the impact electric lighting can have on circadian rhythms. While energy conservation is not a stated part of the WELL Building Standard, many of the features within this concept help minimize energy use. Designers can develop appropriate building masses that allow for greater levels of daylight penetration to support success in this concept.
  • This concept encourages active transportation both for commuting and within a building. Project owners have multiple policy requirements within this section including activity incentive programs (like those offered at Ayers Saint Gross).
  • Comfort. The comfort concept addresses ergonomics, acoustical comfort, olfactory comfort, and thermal comfort. WELL recognizes that different kinds of work require different kinds of spaces, and create different acoustical and thermal conditions. Building a variety of comfort conditions into a building ensures that everyone can maximize their learning and productivity.
  • Mind. The mind concept addresses biophilic design, adaptability, sleep, business travel, and other subjects that impact mental health. Opportunities for innovation are also recognized within the mind concept.

While LEED is an important tool for talking about sustainability in the built environment, I am excited to engage with newer rating systems that allow us to have more human-centered discussions about sustainable design.

Just as LEED and other codes, standards, and rating systems are updated on a regular basis, WELL has been updated this summer. WELL v2 is a pilot program and it’s unclear how long the pilot period will last. As of this posting, projects can choose to register under either WELL v1 or WELL v2 and IWBI assures project teams that when WELL v2 becomes the dominant WELL Building Standard advance notice will be provided.

Check WELL’s FAQ for more on the transition between WELL v1 and WELL v2. You can also reach out to me to learn more about how WELL might be applicable to a project you’re considering at awilson@asg-architects.com.

A New Model for Floating Wetlands

May 10, 2018
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The National Aquarium has an ambitious mission to inspire conservation of the world’s aquatic treasures.

With its prime location in downtown Baltimore on historic shipping piers, the Aquarium wants to localize this mission by restoring aquatic environments in its own backyard, the Chesapeake Bay. To that end, the Aquarium is planning to redevelop an inlet at the heart of its campus with a large-scale floating salt marsh.

These recreated wetlands will serve multiple purposes. They will support greater biodiversity in the Inner Harbor and provide infrastructure for supplemental oxygenation of the water. They will also be an immersive experience for learning about the Chesapeake Bay watershed and its component ecosystems.

Several major technical challenges stand in the way of realizing this vision. First, conventional floating wetlands are costly, and yet they typically last a mere five years. It would be prohibitively expensive for the Aquarium to replace such a large floating wetland structure (planned to be 16,000+ SF) twice per decade.

Secondly, conventional floating wetland systems are topographically flat and not readily calibrated to create a range of microhabitats. They are incapable of supporting the ecological diversity that the Aquarium desires for this unique environment.

Lastly, conventional floating wetlands are not stable enough to support maintenance personnel. For the Aquarium to be able to manage such a landscape, the structure needs to be designed with a high degree of stability.

To realize the client’s vision, our designers (and our partners at Biohabitats, McLaren Engineers, and Kovacs, Whitney & Associates, continuing Studio Gang’s EcoSlip concept) had to create a durable and more topographically varied floating wetland.

***

A brief history of Baltimore’s Inner Harbor: in pre-Columbian times, there was tremendous biodiversity in this zone of the Chesapeake Bay. With the rise of the Industrial Revolution, the area became a major shipping port. Hard infrastructure development mirrored rising urban populations into the early 20th century, replacing natural shorelines. Humans reshaped the harbor to suit the needs of industry and shipping, which resulted in lost habitats and waning species diversity.

The heavy industry eventually faded, and in the 1980s the Inner Harbor was one of the first post-industrial waterfronts transformed into a cultural amenity. Unfortunately, while the land surrounding the Inner Harbor’s water was revitalized, the water itself was largely neglected.

Another significant development that affects the health of the Chesapeake Bay is sprawling urbanization throughout much of its watershed. Hard surfaces cover soil and prevent infiltration of rain water into the ground, so when rain falls on buildings and pavement, it carries lawn fertilizers, pet waste, and road salts into storm drains. Leaks in an aging network of sewer and stormwater pipes, running underneath the city, also added excess nitrogen and phosphorous to Inner Harbor waters. This polluted urban stormwater runoff joins suburban and rural runoff and ultimately flows downstream into waterways like the Inner Harbor. Excess nitrogen and phosphorous, transported in polluted stormwater runoff, is utilized by naturally occurring phytoplankton species and fuels an endless cycle of algae population explosions and crashes throughout the Inner Harbor. When the excess fertilizers that enabled the algal blooms to occur are consumed, a massive die-off of phytoplankton follows. The dead algae sinks to the bottom and provides food that fuels a major bacterial bloom. The rapidly growing bacteria population uses up all the available dissolved oxygen in the water and effectively smothers fish, crabs, and other aquatic life.

Reversing years of environmental degradation and creating a renewed and thriving ecosystem requires a large-scale intervention capable of delivering a wide array of ecological services. Floating wetlands were a natural choice for the Aquarium’s project. 

However, as noted above, conventional floating wetlands have some significant drawbacks. They are typically made of polyethylene terephthalate (PET) injected with marine foam for buoyancy. Plants are placed in drilled holes to allow their roots to reach directly into the water. The PET layers are typically flat with upper layers extending out of the water – a form that does not mimic the varied topography and microhabitats of most wetlands or tidal shorelines. Thus only a limited number of aquatic species can thrive in them (falling well short of the Aquarium’s ambitions for this project).

Additionally, with time, biomass accumulates from plants and bivalves that colonize the PET mesh, causing the entire wetland to sink under its own weight. 

Therefore, while current models of floating wetlands can serve decorative and educational purposes, they are ultimately more akin to a flower show exhibit than to a real-life habitat that is both durable and functional enough to achieve the Aquarium’s objectives. We had to develop a new floating wetland model and adapt an array of technologies from other disciplines to realize our goals.

***

In collaboration with the Aquarium and our multidisciplinary team of scientists and engineers, we designed a new kind of floating wetland. It improves upon the technologies of conventional floating wetlands while remedying their shortcomings in terms of habitat-creation capabilities and the lifespan of the final installation. These new technologies and variables have been prototyped and are currently being tested within the harbor on the Aquarium’s campus.

First, we addressed the issue of topography.

In lieu of a flat floating sheet of PET, our team created a layered topo-model with varied planting surfaces at different elevations, some submerged, relative to the water surface. In the middle of the prototype, a deeper channel provides habitats analogous to shallow salt marsh tidal channels. On the edges, the layers stack up to simulate the low and high marsh environments of the Chesapeake Bay. The prototype also features airlifts and air diffusers, which help to oxygenate and continuously circulate the water and prevent water stagnation in the channel and around the outer edges of the form. All together, these interventions create a variety of microhabitats, which will be utilized by a greater diversity of species and life stages of those species.

Secondly, we addressed the issue of buoyancy. Conventional floating wetlands have what is called static buoyancy from integrated marine foam, which means they can generally restore equilibrium in response to pressure (ie, they don’t capsize or sink easily). Our design adds a rigid support structure underneath the PET layers with capabilities for adjustable buoyancy. This “skeleton” is made of high density polyethylene (HDPE) pipes and pontoon structures that provide the wetland with ballast.

Adjustable buoyancy is essential to longevity. As the plants grow and become heavier, the PET bed can be raised or lowered by pumping water into or out of the pontoons as needed. This design feature also allows for easier maintenance and unique research opportunities. The pontoon structure acts similarly to a ship’s ballast system, whereby trim and list are controlled through adding and removing water. That way, the elevations of individual areas of wetland can be controlled, rather than solely raising and lowering the entire structure uniformly.

The reserve buoyancy system within the PET layer is one of the most difficult and sensitive portions of the design. As buoyancy is directly related to the weight of water displaced, PET mesh itself has very little buoyancy in reserve to counteract the added weight of maintenance workers and waves. To address this issue, we filled hollow cavities in the PET layers above the waterline with marine foam, which is engineered to provide added buoyancy and stability to allow people to stand on the edge of the wetland without it swamping. The foam cavities are carefully spaced in linear strips to avoid interference with plantings.

Additionally, we added a cementitious bonding coating to the PET to increase longevity with regard to ultraviolet degradation.

The 200-SF prototype was shop-fabricated, transported in pieces, and then assembled in a shipyard on the Middle Branch River before being towed to its current position in the Inner Harbor in August 2017. Aquarium staff then planted it with over more than 1400 plugs of native plants. (The staffers were pleased to report that the wetland was stable and firm underfoot—a pleasure to work on compared with the small conventional floating wetlands that have been used on a small scale around the Inner Harbor.) Every square inch of this ecological powerhouse provides opportunities for a diverse range of organisms to grow, colonize, molt, spawn, or eat.

***

Nine months into the experiment, preliminary results are promising.

Almost immediately after implementation, Aquarium scientists observed a rapid colonization of the submerged woven PET material by biofilms, a type of beneficial bacteria that creates a sticky, living coating of the vast PET surfaces. Biofilms feed on excess nitrogen and other nutrients in the water and are the first step towards reaching broader biodiversity and recreating a more natural and multi-layered food web.

By the third day, schools of killifish moved into the prototype’s central channel, and a blue crab was observed molting in the protected shallow water of the new habitat. More fish, anemones, and crustacean species soon followed, along with the arrival of larger species like wading birds and muskrat. The recreated wetland has brought several native species back to the Inner Harbor and into full view of people passing by.

Going forward, the performance of the prototype will continue to be measured. Its impact on water quality will be monitored using data collection equipment installed nearby in the same inlet. This information will help us to calibrate and refine the design of the floating wetland system, so that it has maximum impact when it is fabricated at full scale.

We’re excited to see what’s next for the Aquarium, the Harbor, and the Bay, and what role our newly designed wetlands can play in improving these vital and beautiful places.

 

Jonathan Ceci, Shelly Drees, and Amelle Schultz contributed to the writing of the article.

Green Week 2018: The Carrot Awards

April 18, 2018
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Ayers Saint Gross hosts an annual Green Week to advance sustainability literacy within our staff so we can provide better high-performance designs to our clients. We use this time to:

  • Evaluate our performance in the AIA 2030 Commitment, a voluntary program of the AIA in which we report the predicted energy use intensity of our whole building projects and the lighting power density of our interiors projects.
  • Recognize the most energy efficient whole building project and interiors project under design with the annual Carrot Awards to inspire other projects to strive for greater energy efficiency.
  • Share information colleagues have learned through project experiences, professional certifications, and attendance at conferences.

Since Green Week’s inception in 2013, every year’s programming gets more robust and more engaging. Last year’s Green Week included five sessions and awarded 99 continuing education units to our staff. This year hopes to top those numbers by offering seven sessions across all three of our offices.

So what exactly is a Carrot Award and who are this year’s winners? Sustainable design is sometimes oversimplified to as “carrots and sticks” process, in which carrots are enticing incentives that inspire great design and sticks are cumbersome requirements design teams have to meet. We believe sustainable design is great design, so high-performance projects are a carrot to us. Our highest performing projects under design in 2017 are aspirations for every project in our firm to reach for.

This year’s whole building Carrot Award goes to Washington College’s Semans-Griswold Environmental Hall in Chestertown, Md. It is a new construction project of approximately 11,000 GSF that will support academic and lab spaces for environmental programs and the Center for Environment & Society at Washington College. The project is working toward a Petal Certification under the Living Building Challenge and is predicted to have an energy demand 71% less than baseline. The remaining energy consumption of the building will be offset by on-site solar power which will allow the building to achieve net-zero energy operations annually. To achieve this extraordinary level of energy savings, the project prioritized appropriate building orientation to maximize passive heating and cooling strategies. It will also optimize on-site solar production. A highly efficient geothermal heating system supports the project’s capacity to meet all of its HVAC demands without any on-site combustion.

The project is designed to use daylight whenever possible and supplement as needed with efficient LED lighting. End users have also strategized with designers about how to minimize plug loads, as these become a higher percentage of the total end use of energy in net-zero buildings than in other buildings.

This work would not be possible without the collaboration of an engaged client and our teams at Gipe Associates and CMTA.

This year’s interiors Carrot Award goes to our renovation of George Washington University’s Marvin Center. This student collaboration space in Washington, DC acts as a campus living room and decreases lighting power density by 73%, nearly three times the current AIA2030 reduction target, through daylighting and LED lighting.

Congratulations to this year’s winners, and be on the lookout for more sustainability-focused projects from our firm. For more on how Ayers Saint Gross approaches sustainable design, see our firm’s sustainability strategy, Take Action.

Ayers Saint Gross at AIA DC’s Building Enclosure Council

March 26, 2018
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If you’re in the greater Washington DC area this week, I hope you’ll join me on Tuesday March 27 for a lecture sponsored by AIA DC on an in-depth case study of a unique approach to a high-performance renovation.

Over-Cladding for Thermal Performance and Building Resiliency

The Nelson Harvey Building patient tower occupies a dense urban site in the heart of the Johns Hopkins Hospital campus in Baltimore, Maryland. Ayers Saint Gross teamed with Wilmot Sanz to renovate the exterior and interior of the nine-story, 33-year-old, 118,500-SF building. The innovative and sustainable approach in developing a new hybrid building envelope combines high-performance over-cladding with the existing envelope. The result is a modern design aesthetic that is energy efficient, environmentally sustainable, and highly resilient. In addition to new exterior over-cladding systems, the renovation includes new pat ient rooms, the first-floor lobby, main entrance, and plazas.

After attending this course, participants will be able to:

  • Identify the code implications related to exterior enclosure on existing infrastructure that inform design decisions in a repurposing project;
  • Describe the role that technology plays in assessing, coordinating, and implementing design strategies for new enclosure design on existing infrastructure;
  • Examine the impact of design decisions related to cladding materials, fenestration, roofing, and insulation on the constructability of a new enclosure design; and
  • Discuss the various strategies to future-proof buildings through innovative design systems that address short-term and long-term building enclosure performance and sustainability objectives.

Presenter
Dan McKelvey, Associate Principal, Ayers Saint Gross

Details
Tuesday, March 27, 2018
6:00 PM – 8:00 PM
District Architecture Center
421 7th St NW, Washington, DC 20004

Credits
2.0 HSW | LUs

SITES 101: Creating Sustainable Landscapes

December 20, 2017
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Most people connected to the AEC industry are by now well familiar with Leadership in Energy and Environmental Design, more commonly known as LEED, the world’s most widely used green building rating system.

Less familiar to many is the Sustainable Sites Initiative, aka SITES. SITES is, broadly, LEED for landscape. The rating is a way of helping designers set and reach sustainability goals with clients. The system was developed through an interdisciplinary effort by the American Society of Landscape Architects Fund, The Lady Bird Johnson Wildflower Center at The University of Texas at Austin, and the United States Botanic Garden. After a rigorous testing period, the program was transferred to Green Business Certification, Inc (GBCI) in 2015. It’s a relatively new force in sustainability for the built environment, and in my opinion, it’s a powerful one. I am excited about how SITES can help create a holistic approach to sustainability in the built environment.

Every SITES prerequisite or credit is based on the idea of ecosystem services. Ecosystem services are the benefits we receive from natural systems, comprised of both the living and the nonliving components of the landscape. SITES sorts these benefits into four categories: provisioning, supporting, regulating, and cultural. Below are more details on these categories and some suggestions for how designers and clients can thoughtfully approach the SITES certification process.

  • Provisioning. Any useful product produced by the landscape would be the result of a provisioning system. These products include food, lumber, energy supplies, medicines, and similar items. These credits can be earned through a variety of approaches such as incorporating edible gardens, or using local quarries for stone elements on a site.
  • Supporting. Supporting systems keep ecosystems healthy. They include soil formation, photosynthesis, habitat creation, and biodiversity. Credits for supporting can be reached through both design intervention and preservation. Much of the program focuses on preserving healthy soils and ecosystems that would take years of in-situ cultivation to recreate. Improving degraded sites through soil remediation and using native planting to improve habitat value are another way to earn credits.
  • Regulating. Regulating systems produce benefits by maintain larger systems through carbon sequestration, local and global climate regulation, and water and air cleansing. A common regulating technique is the use of bioretention and filtration to clean water and recharge the water table. Biofiltration facilities allow stormwater management infrastructure to function in a healthy way rather than adding to city storm water systems. These systems can often add a cultural value as well by improving the aesthetic of a place.
  • Cultural. This category includes a wide range of tactical choices, like outdoor exercise and gathering spaces, highlighting local icons, and healthy benefits. It’s everything from the creation of a healing garden near a hospital to the inclusion of native plants in a landscape design.

Personally, the thing that excites me most about the SITES system (and about being the first SITES AP at Ayers Saint Gross) is the ability to help a landscape project improve a place’s ecological functioning. Living landscapes are unique for their ability to recharge systems and can make a place function better than before intervention. Too often we see a LEED certified building that is a sustainable island in a landscape that doesn’t support the same high-performance objectives. SITES is a terrific tool to help align the development and management of land with innovative sustainable design.