COVID, sustainability drive college building design
Colleges and universities have been sustainability trendsetters over the past several years. COVID-19 has required designers to think differently
- Kim Cowman, PE, LEED AP, National Director of Engineering, LEO A DALY, Omaha, Nebraska
- Daniel S. Noto, PE, LEED AP, Owner, Noto Consulting Group LLC, Roswell, Georgia
- Coral Pais, PE, BEMP, LEED AP BD+C, WELL AP, Mechanical Engineer, DLR Group, Cleveland, Ohio
- John M. Rattenbury, PE, LEED AP, Vice President, Cannon Design, Boston
- Luke Richards, PE, Project Engineer, RMF Engineering Inc., Raleigh, North Carolina
- Simon Ubhi, PE, LEED AP BD+C, Principal, Henderson Engineers, Los Angeles
- Toby White, PE, LEED AP, Associate – Boston Fire and life Safety Practice Leader, Arup, Boston
What’s the biggest trend in college and university buildings?
Kim Cowman: Health and safety is the biggest trend right now in college and university buildings. Our clients want to be prepared for the next crisis like COVID-19 that may require them to use space differently. For example, a lecture hall that once sat 150 students may be used for a class of 50 students. A residence hall may need to be able to serve as a quarantine space. Looking ahead, they are also going to be thinking about the energy impact of modifications to HVAC systems to address COVID-19. A common response to COVID-19 has been to increase fresh air intake. That has negative energy use and cost implications. I think they will be asking us how they can make their buildings safe without incurring additional energy and cost.
Daniel S. Noto: The biggest trend in HVAC design, ever since early 2020, has been retrofitting existing systems to help mitigate COVID-19 spread on campuses. All design considerations must first go through a test of “How does this design ensure that the space is safe for in-person learning?” before going on to more detailed design questions.
Coral Pais: Campuses are moving beyond just developing sustainability plans or signing on to commitments such as the American College & University Presidents’ Climate Commitment. They are not moving into a more robust implementation phase of these commitments. This includes live tracking and better reporting of the greenhouse gas emissions, electricity and gas usage, as well as waste and emissions from transportation.
John M. Rattenbury: Before the pandemic, I would say sustainable design. Those going into higher education, for the past decade or more, tend to be highly environmentally conscious and that trend is increasing. From new construction of academic buildings, laboratories and residence halls, everyone wants and expects energy efficiency, water use reduction and services that encourage recycling. Since the pandemic has hit, there is now a focus on air quality. With an airborne virus, colleges are seeking better methods for increasing air changes and providing high-efficiency filtration to maximize safety within their facilities.
Luke Richards: RMF has seen a commitment from colleges and universities to shift to more sustainable designs, balancing long-term cost saving measures against increased upfront costs. Our local clients are requiring new facilities to be certified by such sustainability standards as U.S. Green Building Council LEED or the Green Building Initiative’s Green Globes. This involves designing above code minimums and implementing better indoor air quality practices, energy saving measures and sustainable material sourcing. Budgets are important in the decision-making process, though while these facilities are designed and built for long-term usage, life cycle cost analysis can provide information for determining economic paybacks. In an effort to attract top faculty and student talent, higher education campuses are using sustainably designed facilities within their marketing.
To help reduce COVID-19 transmission, what types of engineering solutions are you offering colleges and universities?
Luke Richards: One of the simplest COVID-19 mitigation strategies is the implementation of increased ventilation. Increasing the proportion of outdoor air relative to return air has the effect of diluting contaminants by either dilution or removal through pressurization and relief air paths. Designers and building owners should understand the consequences of this solution and that it is not simply adjusting set points or damper settings. The capability of existing equipment heating and cooling systems are determined during design with engineered entering and leaving air conditions. In the extreme heating and cooling seasons, the existing HVAC equipment may not be able to handle the increase in outdoor airflows due to higher sensible and latent loads needing to be conditioned. Adverse effects can increase indoor temperature and humidity.
Toby White: Early into the pandemic, Arup began to look for creative ways to improve and inform design to address this new risk and perceived “new normal.” Arup’s crowd modeling software MassMotion had been developed over a decade ago to provide insight into efficient and user-friendly design of spaces, particularly transit terminals. Our developers and engineers were able to quickly modify our software to analyze physical distancing scenarios and collect simulated data on occupant exposure and proximity to one another. This tool allows designers and architects to experiment with different wayfinding strategies, vertical transportation queuing and variations in occupant arrival and departure scheduling by comparing relative output data of the various design scenarios. With this data, the designers can make informed and deliberate decisions about how their space can be used while promoting social distancing and limiting occupant-to-occupant exposure.
Kim Cowman: Our first recommendation is to verify basic operation of the current HVAC systems. Are they performing per design and code requirements? Over time mechanical system components can fail and system overrides inadvertently left in place in building management systems can contribute to under-ventilation of spaces and impact the health of occupants. A focused commissioning exercise will validate the operation of the units, ensuring that minimum ventilation requirements are being met and that all components (valves, dampers, control logic) are operating as intended.
Once systems are verified to meet original design and code requirements, we then consider improvements to filtration and increases to the relative humidity in occupied spaces. Research shows that between 40% to 60% relative humidity significantly reduces pathogen spread and increases our bodies’ ability to protect themselves from pathogens. The challenge in increasing humidity is that some existing systems are not designed with supplemental humidification and that exterior envelope construction may be at risk for condensation with increase humidity levels. Care must be taken to determine the overall building can operate at a higher RH without damage.
We then will discuss additional air cleaning technologies with the owner. Technologies such as UV lights applied to cooling coils have been used for many years to reduce microbial growth and aid in cleaning of coils. They are also a proven mitigation technology for pathogens when provided at appropriate output levels. Additional strategies to improve indoor air quality include increasing existing UV system outputs and incorporating UV systems at air handling units. When it comes to newer air cleaning technologies that have recently received more press and attention due to the pandemic, our approach with clients is to discuss the potential unknowns of these systems due to limited real-world application and testing and potential risks due to the lack of long-term data on performance.
Coral Pais: Long range transmission of infectious aerosols can be reduced through optimization of ventilation and filtration. Most buildings have the means of bringing in outside air. The question is: “Is it enough to properly dilute the space based on the number of occupants at a given time?” In cases where there may be a concern, we recommend short term or long-term monitoring of IAQ before applicable solutions are proposed for a space given its use and function.
Daniel S. Noto: We offer a review of the existing HVAC system and work with the university or college to develop a cost-effective plan to renovate and/or upgrade individual systems to promote a safe environment for in-person learning. This includes upgrading filtration (higher MERV ratings), adding ultraviolet lighting to existing air handlers and, when possible, increasing outside air percentages, without compromising humidity control.
What future trends should engineers expect for such projects?
Coral Pais: Colleges and universities are driven by long-term goals. They understand their buildings are going to last for decades and so they are naturally inclined toward a sustainable mindset. As an industry, we are becoming more aware of the efficiency of microgrids and campuses are great opportunities where independent grids can be applied. We were part of a project that provided space for the expansion of a mechanical plant that could connect all of the arts building on the south part of a campus — the solution was forward thinking and well planned.
Luke Richards: A significant importance is being placed on IAQ. The ongoing COVID-19 pandemic has colleges and universities retrofitting existing facilities to promote the health of occupants, faculty and students. One part of best IAQ practices includes filtration of contaminants within the building envelope. The biggest trend we are seeing is a push for bipolar ionization because it is relatively easy to retrofit in existing systems and has a fairly low first cost for the potential benefits. However, this is an emerging technology and not all manufacturers of the technology are meeting the claims they make and, in some cases, can even generate ozone into the building air stream.
Looking ahead, how do you think these buildings will be designed differently to meet new health challenges brought on by COVID-19?
Luke Richards: COVID-19 appears to be here to stay and the lessons learned from this pandemic can be implemented to minimize other airborne pathogens such as the yearly flu. Specific to HVAC systems, new buildings will need to be designed to exceed the code-minimum ventilation requirements and will need to implement energy recovery strategies to offset the increased energy consumption, while the same energy code requirements still apply. Touchless plumbing fixtures are becoming more popular as well to minimize the spread of germs in public spaces. While restroom fixtures had begun to transition to touchless flush valves and lavatory fixtures pre-COVID-19, we have recently seen a trend in touchless technology being used in laboratory fixtures.
Kim Cowman: Moving forward from the pandemic, the focus will be on providing a healthy indoor environment. Clients are now more educated on the impact of IAQ, filtration levels and ventilation rates on the spread of pathogens. So are the students and faculty occupying these spaces. As designers, we will engage in more conversation with facility staff and look toward designing systems that exceed the minimum standards for ventilation and filtration. Our goal in the long term is to provide resilient systems capable of accommodating increased filter efficiencies and the associated increase in pressure drop and fan energy requirements needed to operate at increased levels of ventilation during high-risk times of year. We may also see a need for additional monitoring of indoor air conditions beyond temperature to include CO2 levels or particulate levels that can be displayed for building occupants, providing information on the quality of the indoor environment they are occupying.
John M. Rattenbury: At the onset of the pandemic, an institute in Cambridge, Massachusetts, embarked on an initiative to obtain sewer samples from individual residence halls. Science has shown that the coronavirus is shed by humans through the digestive tract in much higher concentrations than in a nose swab sample, thus allowing for early detection. However, finding suitable locations to tap into the sewer pipes proved to be a challenge because the piping systems are not designed to provide for single point sampling with easy access. I can see design practices change to allow for sampling wells.
Describe a university science or engineering lab you have helped design and innovative engineered systems within it.
Kim Cowman: Brace Laboratory, completed in 1906, is one of the first buildings constructed at the University of Nebraska – Lincoln. The University engaged LEO A DALY to conduct a feasibility study, then to conduct a full renovation for use as an undergraduate lab facility. The resulting project restored the original tiered auditorium, introduced biology laboratories and facilitated the university’s exploration of collaborative classrooms. The renovation project also restored some of the historic details of the original design throughout the interior.
The renovations provided program specific updates, including three life sciences laboratories and lab support spaces, a classroom for the university’s Technology Transforming Teaching (T3) initiative, two general purpose classrooms, staff offices, an auditorium that expanded seating capacity from 160 to 186 seats, improved technology, updated lighting and acoustics, a new HVAC system, LED lighting, all new windows, continuous insulation added to the exterior walls, new wood main entry doors with glass panels (installed to meet original design intent and bring natural light into the lobby) and refinishing and reinstalling of the original cast iron building sign that was found in the wall above the boarded-up transom at the entry door.
The key engineering challenge was the installation of air conditioning in a historic building that has never had it. The design team had to be very resourceful about how and where we located equipment, which included repurposing the building’s attic as a mechanical room and creating routings the new air conditioning systems. It was a significant design achievement to be able to incorporate the new systems while still maintaining the original design intent and aesthetic of the century-old building, while enabling easy maintenance and future removal.
Luke Richards: RMF recently completed the design for a vivarium science facility intended to research the slowing and elimination of Alzheimer’s. This renovation to an existing laboratory facility will be a mix of animal housing and wet laboratory/testing spaces. HVAC equipment dedicated to the renovated spaces was designed to maintain specific temperature and humidity set points while delivering between 10 and 20 air changes per hour of once through or 100% outdoor air. The dedicated air handling unit included initial air filtration with pre- and intermediate filters, hot water preheat coil, chilled water cooling coil, supply air fan array with fan redundancy and final HEPA filtration.
Energy recovery is crucial for reducing energy consumption in the HVAC systems while maintaining safety for the researchers and husbandry staff. A glycol energy recovery loop was designed to use the dedicated animal exhaust system as a heat sink (or source depending on the season) to precondition the outdoor air being delivered to air handling unit coils. Any air that is conditioned and supplied to the spaces is exhausted and a portion of that energy should be recovered safely. The energy transfer between the supply and exhaust air streams occurs through a closed loop hydronic system, guaranteeing that exhaust contaminants are not bypassed back into the supply.
Simon Ubhi: 850 PBC is a collaborative, seven-story research facility in the heart of Phoenix. Designed for LEED Gold Certification, the building houses researchers from Arizona State University, Maricopa Community Colleges and commercial research firms. Henderson engineered the building systems with resilience, occupant wellness and efficiency in mind with 50% water use reduction and 17% energy savings over ASHRAE 90.1-2010. As wildfires increasingly impact the southwest, MERV 15 filtration will protect occupants and critical research from harmful smoke. Redundancy in the power, equipment and controls for essential systems will ensure continuity of service.
Tell us about a recent COVID-19 project you’ve worked on that’s innovative, large-scale or otherwise noteworthy.
Kim Cowman: At the start of COVID-19, in the spring of 2020, LEO A DALY thought leaders conducted a significant R&D project studying the potential to reduce pathogen spread by increasing relative humidity in buildings. Building upon Dr. Stephanie Taylor, M.D.’s March 2020 report in the Annual Review of Virology, which found that interior relative humidity levels of at least 40% can substantially suppress all methods of COVID-19 spread, we studied the building impacts of increasing relative humidity on a variety of building types. Our study, titled “Increasing Winter Humidity in Buildings to Reduce the Spread of Infectious Disease,” was cited in a number of publications and raised the level of discourse on design responses to the pandemic. In addition, our thought leaders teamed with the University of Nebraska School of Medicine to present in a number of industry forums. This research has since gone on to become a key element of our design approach for improving health.
How are engineers designing these kinds of projects to keep costs down while offering appealing features, complying with relevant codes and meeting client needs?
Coral Pais: The most successful strategy that I have seen in delivering the best option to a client is when all members of the team are involved including the architect, owner and construction manager. Involving the construction manager early in the design process allows them to understand the goals of the project and be part of a solution that can balance costs with efficiency.
How are college and university buildings being designed to be more energy efficient?
John M. Rattenbury: College and universities are making far more use of energy recovery systems.
Simon Ubhi: Integrated design and iterative energy modeling are essential to designing high performance buildings. For 850 PBC, we layered strategies to achieve an overall energy savings of 17% over ASHRAE 90.1-2010. As a developer-driven laboratory project with university tenants, this project proves significant efficiency can be achieved within a reasonable budget. In the central plant, we used variable speed systems, low-temperature heating water, air and waterside economizers and run-around energy recovery between laboratory exhaust and air handling units. Within the spaces, we maximized daylight harvesting with dimmable LED lighting and integrated the lighting controls to reduce the laboratory air changes during unoccupied periods.
Coral Pais: Large university campuses have developed their own sustainability standards that are part of the project requirements. This provides a platform for the design team to stretch energy-efficient design goals. On the operation side, campuses are working with commissioning agent teams and controls contractors to continuously identify opportunities for savings.
Luke Richards: Colleges and universities are beginning to require the certification of new facilities to a sustainability standard such as LEED. These facilities are built for long-term usage, where sustainability and energy saving measurements are most beneficial and have time to realize economic paybacks. RMF has been designing more of these facilities with energy recovery strategies as a way to enhance overall building efficiency.
With the current trend to increase ventilation in campus buildings, due to both the COVID-19 pandemic and best IAQ practices, problems can arise from existing HVAC equipment not being designed for the increased loads required for conditioning and meeting indoor space/temperature set points. The climate in the Southeast is both warm and humid, requiring any outdoor air to be dehumidified before being supplied to building spaces. Pretreating outdoor air with energy recovery coils or wheels can reduce the overall energy needed to meet indoor set points and assist existing HVAC cooling/heating coils that were originally designed with more recirculated air.
Toby White: The recently completed Colby College Athletic Center, which I project managed was designed to reduce energy usage significantly. This project incorporated an assortment of low energy strategies including energy recovery wheels on all air systems, daylight harvesting to reduce electric lighting energy and capturing excess waste heat from multiple sources to heat the indoor pool in the aquatics center.
What is the biggest challenge you come across when designing such projects?
Luke Richards: The biggest challenge we face is typically the project budget. Many of the university projects that RMF works on are funded by the state and overages are unacceptable. Designing facilities that go above code-minimum designs and implement more energy efficient designs have an increase in cost due to either additional equipment being required or simply more expensive equipment. Design decisions are made looking at payback periods to make sure investments will yield reduced energy consumption costs over time. We use life cycle cost analysis combined with energy model simulations to make educated decisions and typically recommend energy saving measures that have at least a 10- to 15-year payback for our higher education clients.
Daniel S. Noto: When designing new projects for colleges and universities, the biggest obstacle, as usual, is securing the funding necessary to invest in a more efficient design. The budget for a project that puts Energy Efficiency high on the priority list often has to be slightly higher than your “standard project.” Educating the facilities, engineering and design staff at the school can help make the budget and scope process run more smoothly.
What is the typical project delivery method your firm uses when designing these a facility?
Luke Richards: Our university and college projects are typically built using the design-bid-build method. Campuses will advertise for design teams that have significant project history and expertise in the area of their project type to interview. Once designer selections are made, it is the responsibility of the design team to develop construction drawings and specifications in line with the predetermined budget or provide ongoing budget guidance as necessary. The completed design documents and specifications are then bid by contractors, with the lowest bid being selected. RMF recently completed a project using the design-bid-build delivery method.
The university’s request for qualifications had specific project goals and an initial budget. RMF was selected as part of a local architect’s design team where we both shared a long history of working on this particular campus and designing these types of teaching laboratories being constructed. The design team worked closely with university project managers and research faculty to ensure all stakeholder goals were realized. Submissions for review at the 30%, 60% and 90% completion milestones included design team cost estimates to ensure the project budget was in line with current construction costs. The use of add alternates allowed the university team to determine the base project scope within their budget but also allow for additional renovations should the contractor bids come in favorably.
What technologies are you incorporating into design that is used in classes or laboratories? What innovative ways are colleges and universities including building systems to assist with coursework?
Kim Cowman: The pandemic has increased the focus on technology in the classrooms to accommodate remote and distance learning capabilities. This is driving conversations and design solutions on how to best integrate distance learning into not only traditional lecture classrooms but into learning and teaching labs. Incorporating A/V subject matter experts into the design conversation early is critical to determine the most appropriate technology solutions, which could include additional and new camera technologies to assist in screen capture on not only white boards but also lab demonstration spaces and leveraging student and educator personal electronic devices to interact with digital platforms.
What are engineers doing to ensure such projects (both new and existing structures) meet challenges associated with emerging technologies?
Coral Pais: Education and ease of operation. As designers, it is important to educate owners about technologies that can meet the design intent for a building but it is also important to recognize that if a facilities/operation team is not comfortable using a technology, it has potential to not be successful.
Kim Cowman: To accommodate the increase in remote learning needs, we’re seeing the convergence of audio-visual technology and information technology infrastructure. Leveraging a building network to run A/V and other systems gives scalability for future technology integration and moves away from proprietary equipment. The challenge for engineers is planning and sizing data and IT rooms to accommodate merged systems. In new construction, this can lead to larger and additional room considerations integrated into space planning efforts. Renovation projects may need to look at phasing of the construction process to build new, appropriately designed data rooms for future tie-over connections while keeping the legacy systems and data rooms operational during construction.
Simon Ubhi: Designing these systems to be as flexible/adaptable as possible. Technology/building use is changing at a rapid pace. Implementing modular lab planning and associated utility system distribution is one way to be flexible for emerging technologies. Understanding what available spare capacity and diversity is designed into systems is crucial for maintaining/ensuring a facility’s ability to adapt into the future.