Improving High-Performance Facades Through Post-Occupancy Evaluation  

While a great deal of time, effort, and expense typically goes into designing, fabricating, fine-tuning, erecting, and commissioning a high-performance facade, once a building is up and running, the building team is typically on to the next project and the owner assumes the facility is performing as intended.

Photo courtesy of Kirksey Architects

Post-occupancy evaluations are important to ensuring that high-performance facades are actually performing as designed. Such a study was completed for the Energy Center Three building in Houston.

However, due to the complexity and number of systems that must come together in a high-performance facade, more often than not, the system is not performing at its optimal level. A high-performance facade is defined as a building enclosure that employs complex concepts for daylighting, solar heat gain control, ventilation, and space conditioning based on the use of advanced materials, automated dynamic components, and integrated climate controls.

“High-performance facade systems are inherently complex and growing more so,” explains Mic Patterson, Ph.D., LEED AP BD+C, immediate past president, ambassador of innovation and collaboration, Facade Tectonics Institute (FTI), Los Angeles. “They are consequently sensitive to quality issues in design and execution, particularly in their fabrication and installation.”

Furthermore, the facade is the most expensive part of a building, and the building’s energy consumption, daylighting, HVAC, comfort, and sometimes acoustics are highly dependent on it.

“In general, post-occupancy evaluations (POE) are sorely needed as a best management practice for all design projects. With any large capital investment promising multiple attribute returns, it would be unwise not to perform some level of POE and commissioning effort,” says Colin Rohlfing, AIA, LEED AP, vice president, director of sustainable development, HDR, Chicago.

Preaching the importance of POEs, Patrick Thibaudeau, vice president, sustainable design, HGA Architects and Engineers, Minneapolis, explains that they show areas where occupant comfort and satisfaction require engaging building occupants in a process of understanding and improving the overall performance of the building. “The post-occupancy phase of a project is becoming increasingly important since it involves the completed project and the actual workings of the people in the building,” he says.

Photo courtesy of Perkins Eastman

Useful POE information gathered from another K–12 design led Perkins Eastman to reduce window sizing and add an internal lightshelf at Dr. Martin Luther King Jr. School in Cambridge, Massachusetts. The result is that students and teachers rarely turn the electrical lights on.

The Facade’s Interworkings

Drilling into the details of how facades work, Heather Jauregui, LEED AP BD+C, O+M, CPHC, sustainability specialist, Perkins Eastman, Washington, D.C., explains that from a thermal comfort and energy perspective, the more well-insulated and airtight an assembly, the greater the risk that construction and/or detailing mistakes can be made. If this occurs, moisture can accumulate within the insulation and eventually lead to mold/mildew issues or degradation over time.

Furthermore, from a daylight perspective, the facade has a tremendous impact on how much daylight enters a building and how well that daylight is controlled. “The orientation, window-to-wall ratio, window proportions and location, glazing parameters, and shading elements all impact where and how daylight may be transmitted to the interior and how these elements combine to deliver significantly different results,” she says.

“Studying the assembly after construction can help catch potential errors before they may become an issue down the road,” she continues. “This can also lead to a learning opportunity for both the design team to improve detailing on high-performance facades on subsequent projects and for the construction team to improve on how the envelope comes together to minimize potential issues.”

In fact, Jauregui reports that after conducting POEs on multiple past projects, Perkins Eastman discovered that designing to textbook lighting levels may actually over-light interior spaces in relation to occupants’ real-life preferences. This valuable information is currently informing the firm’s designs, as it has revised its daylight targets accordingly.

While key data like this can only be uncovered with POEs, Aulikki Sonntag, Drees & Sommer, Basel, Switzerland, points out that the majority of new-construction high-performance facades, especially those that are custom designed, do undergo significant laboratory testing during early construction phases. This frequently includes a performance mockup and, as required, isolated material testing. “These are typically the responsibility of the curtain wall contractor conducted at and/or witnessed by an independent test lab,” she explains.

Sonntag reports that performance mockup testing often includes water infiltration testing, static with pressure differential; dynamic water infiltration via simulated wind-driven rain; structural testing of wind loads; thermal testing to confirm material and joinery can withstand extreme temperature changes; racking, which is a simulation of building movement; proof load structural, which is 1.5 times the design wind load; and proof load racking that tests cyclic movements and the associated safety factor for the overall design.

“On selected curtain walls, we use infrared cameras to test for bridging and to review if operable windows are working properly with HVAC interoperability,” adds Arathi Gowda, AIA, AICP, LEED AP BD+C, associate, SOM, Chicago.

Additional assessments may include testing the loads induced by window-washing equipment, endurance cycling of moveable components such as shading systems, and cycling of operable elements, which is relevant to maintenance. It’s also important to understand that because high-performing new facades incorporate a large degree of prefabrication, if and when field testing were to reveal performance issues post-occupancy, the ability to address these issues may be somewhat limited, depending on the issue.

“Joinery and anchorage is no longer accessible, and there is no exterior scaffold allowing for field work to be conducted. If a typical condition fails in performance—e.g., air infiltration, water infiltration, or even structural issues—chances for a successful field fix are low,” cautions Sonntag.

“The ability to make any modifications after envelope completion is very limited and expensive, unlike MEP commissioning where you can fine tune the systems after construction,” agrees Stevan Vinci, CET, LFA, LEED Fellow, BECxP, CxA+BE, principal, senior sustainability and building science specialist, building specialty services, Morrison Hershfield (MH), Portland.

With MH’s testing expertise, the firm can help owners sort through the various testing options available and develop a new standard envelope testing strategy for current and future projects.

That said, POEs are still highly recommended, and Sonntag lists a number of scenarios where they are particularly useful:

• When the system has a low degree of prefabrication and the air and weather seals are more dependent on the field labor conditions and ultimate quality of the work.
• There is no repetition on elements, hence there is no typical element to be tested in laboratory which would represent a sizeable percentage of the building envelope condition.
• The system is influenced by other adjacent parts, e.g., acoustic or sound separation via adjacent walls/slabs or intersecting with other wall types.
• The system is not a new construction but works with an as-built condition, e.g., refurbishments/renovations where the as-built cannot be fully replicated in the laboratory.
• The system includes moveable components that are field-installed or might require adjustment in the field and cannot be fully evaluated in laboratory or factory settings, e.g., sunshades/operables and their tie-in into the building control system.
• Components that are related to life safety issues, e.g., electrical components, smoke evacuation, etc.
• The system is technically unique or complex and there is not much historical data available, or the system is an integrated part of the overall energy concept of the building, e.g., temperature flow in multilayer facades or tie-in mechanical system using precooled and or preheated air.

Photo courtesy of Tom Bonner Photography/HGA Architects & Engineers

The results from HGA’s Los Angeles Harbor College Science Complex POE is being used as a benchmark for future projects.

What to Evaluate

Returning to the topic of POEs, once a building is already up and running, the main thing that these studies focus on is any and all assumptions associated with operational energy use and human wellness that the project was designed to achieve.

“The studies often involve an electronic survey that building occupants complete online. In addition, an on-site inspection can be performed to observe building functions and interview occupants to follow up on survey results,” explains Thibaudeau. “The most frequent post-occupancy evaluation is monitoring energy use by obtaining energy data and evaluating it and making adjustments to the building.”

While performance aspects will vary, Rohlfing explains that the parameters that are usually measured include energy use in annual, monthly, weekly, daily, and 15-minute intervals; thermal comfort compliance per the Center for the Built Environment’s Thermal comfort survey; and useable daylight and glare monitoring.

Furthermore, Jauregui emphasizes the importance of studying how the envelope deals with daylight, temperature, moisture, and sound. “For daylight, it is important to look at both how the envelope impacts daylight distribution in the indoor environment and how it impacts glare or visual discomfort. For temperature, many factors impact comfort, so studying air temperature in combination with radiant surface temperature and infrared imaging can give a more accurate picture of comfort.”

Sound should also be evaluated, both ambient and occupied conditions, to assess both persistent background noise issues as well as how material surfaces deal with absorption/reflection of sound.

Solar heat gain is of particular interest to buildings in hot climates, according to Julie Hendricks, AIA, LEED Fellow, vice president, director of EcoServices, Kirksey, Houston.

“Shortly after a building has been constructed, we are wondering if the facade is doing its job of avoiding heat gain and keeping the building occupants thermally comfortable,” she explains. “We have just begun our explorations into this topic, and right now we have a few tools—our solar radiation meter and our thermal camera—that we use to give us some insight into the facade’s performance. The thermal camera gives us some insight into facade leakage and infiltration problems as well.”

For buildings incorporating automated building-integrated shading systems that interface with the building management system and involve sensors, controls, blinds or louvers, and software, it is important to rigorously test and validate that all components are performing as designed, adds Patterson.

POEs in Execution

As Hendricks alluded to, Kirksey’s solar radiation meter takes measurements in BTU per hour, per square foot by pointing the sensor toward the surface being measured. Two measurements are taken, one inside and one outside the window. “Then we take the ratio of the inside measurement to the outside measurement as an approximate measure of the window’s operational SHGC [solar heat gain coefficient],” she says.

By using the solar radiation meter, Hendricks’ team can also see how effective any shading devices might be in combination with the high-performance glass.

Image courtesy of Kirsky Architecture

As part of the Burnett Bayland Gym POE, Kirksy tested the glazing’s SHGC and found it to be consistent with the published manufacturer values.

“The other thing that we do is take thermal camera images of the facades. Infrared thermography detects the infrared energy that is emitted or reflected by materials and creates images that display the surface temperature of objects,” she explains. “Thermal camera images can be used to study heat differences in building materials, which may be caused by thermal bridging, infiltration, or moisture. It is a helpful tool to locate and assess areas of concern in a building facade. We have used our thermal camera to locate moisture leaks in walls and roofs and improperly installed insulation, among other issues.”

To better understand the kinds of scenarios that a thorough POE can help ascertain, Sonntag lays out a number of examples:

• The temperatures and humidity levels when the vents open for natural ventilation
• The solar radiation levels when shading elements are closed to reduce glare issues and overheating
• Within multilayer facades, e.g., closed-cavity facades, the cavity temperatures/humidity levels that would require mechanical-induced air flushing and/or electrical components to be shut down to prevent overheating and damage
• The point where waste heat and heat buildup is ready to be reused by switching from active to passive mode of a building operation
• The wind protection levels of sensitive facade components; e.g., design of exterior skin that allows for the shading system to be operated at windy conditions

In addition to all the technical aspects of operation, the other important aspect of POEs is evaluating users’ comfort and observations.

“A well-designed questionnaire can assess peoples’ perception and satisfaction with how the indoor environment is performing, but this should be aligned with quantitative data assessing actual building performance,” Jauregui explains.

The challenge with actual building performance is there are many variables that may impact how a building is performing, and these may vary significantly over time. Consequently, limiting variables as much as possible and studying an environment for an extended period of time can improve the value of the data collected.

To gather this kind of valuable data, Gensler developed its own pre- and post-occupancy survey tool called the Workplace Performance Index. This can both gather employee input on workplace performance factors before a project is designed in order to inform design decisions and also measure the success of the design solution after the project’s completion.

In particular, the tool assesses four work modes that are considered fundamental to knowledge work: focus, collaborate, learn, and socialize. The tool also contains questions that help the firm’s clients connect workplace design to key business drivers such as employee engagement, satisfaction, and organizational commitment.

The WPI measures the quality of 28 attributes of physical space, such as layout, acoustics, privacy, light, air, and furniture comfort. Information gathered through the survey then informs what is working well and what should be improved by a new design.

Leveraging that Knowledge

Once a POE is successfully performed, the next step is applying that information to the current design, where possible, and to future projects.

“This information gives insight into how satisfied the occupants are with the daylighting, glare, and thermal comfort aspects, how it impacts their work, and if adjustments need to be made for improvement,” says Thibaudeau. For example, “building owners can adjust the layout of furniture in spaces, add or change how internal shading works, and make adjustments to HVAC systems to improve comfort of occupants, especially near the perimeter. In a building with adequate daylight, adjustments can be made to reduce electric lighting.”

Delving into more details on how POEs can inform future daylighting designs, Thibaudeau explains that successful daylighting projects require thoughtful attention to how deep the daylight penetrates into a space; how to avoid bright spots, dark spots, and too much contrast; and assuring the ceiling and walls are lighted. “When the ceiling and walls are well-lit and the daylight is evenly distributed in the space, then the electric lights can be turned off, occupants are satisfied with the light levels, and predicted energy savings can be realized,” he explains.

However, in order to get to that point of success, lessons learned from POEs on other projects can go a long way toward fine-tuning those daylighting designs.

In Gowda’s experience, user feedback from POEs can reveal systematic issues related to facade performance and HVAC response time if there is thermal discomfort in areas of the building. “As building owners, operators, and managers become more service-oriented in competitive markets, POEs serve as a means of solving occupant concerns before they become broader issues,” she explains.

While issues related to building energy operations and indoor air quality can be costly to remedy, other mitigations related to certain aspects of health and wellness for building occupants may be leveraged more immediately, says Rohlfing. And depending upon what the enclosure issues are, acoustic and thermal remediation through films and where workers are positioned can be explored.

Similarly, Jauregui explains, “Although adding more insulation behind a facade may not be feasible at this point, there are things that can be caught and replaced, such as a broken seal in an insulated glass unit or a drainage issue that is resulting in unwanted moisture buildup.”

At the same time, because the facade is a static part of the building, Alec R. Carnes, PE, CEM, HBDP, LEED AP, building optimization practice leader, Heapy Engineering, Dayton, Ohio, points out that improving performance after construction is not easily accomplished since it typically would require opening the system for reworking.

That said, the other important aspect of POE “deliverables” are they key lessons learned for future high-performance projects.

“Design teams will have good predicted and actual performance metrics for enclosure U-value and infiltration rates that can be used as tolerances in future predictive energy modeling. Construction teams can identify numerous insights about their effectiveness of installation methodologies and procedures to ensure that future enclosures avoid faulty installation. And owners and operators can gain insight to comfort issues created by thermal performance, light quality, and acoustics associated with the enclosure,” says Rohlfing.

Capitalizing on the valuable data that POEs have to offer, Perkins Eastman has a database full of multiple past POEs that allows design teams to identify how high-performance facades are actually performing in relation to how they were designed and then tweak current facade designs accordingly.

For example, “measurement of glare, especially combined with occupant feedback on this issue, can help to make the case for more appropriate window-wall ratios and sun control mitigation,” explains Jana Silsby AIA, LEED AP, principal, Perkins Eastman, Boston. “Many clients and designers alike often adopt a position that more glass is always better. However, both qualitative and quantitative feedback from spaces where the glare and solar heat gain are not effectively controlled send a clear message that this is an important consideration for every design.”

Related to the window-to-wall ratio issue, Hendricks relates that her firm’s POEs often demonstrate that window assemblies designed with shading devices are, in fact, effectively reducing solar heat gain.

Image courtesy of Kirsky Architecture

Kirksy’s POE for the Burnett Bayland Gym reported that the glazing and shading designs are effectively reducing the outdoor solar radiation levels by more than 95 percent.

“Shading devices are expensive, and it can be difficult to persuade project teams that they are necessary. I’m glad to have measured results showing that our shading devices do work well,” she says.

In addition to helping architects and contractors with future facade projects, building owners can also leverage the POE insights garnered from their project to help with future decisions, for example, whether to go with a certain product or shading configuration the next time around.

POEs in Action

Taking a look at a few POE projects, Perkins Eastman evaluated the post-occupancy daylighting performance at Dunbar Senior High School in Washington, D.C.

Designed to achieve LEED daylight targets, the classroom was oriented east-west, appropriate shading was applied to the south facade, and ceilings were sloped to maximize daylight penetration into the interior.

Upon completing a POE, something quite interesting emerged: While the building was designed to meet LEED targets, in actuality, the space was considered slightly over-lit by building occupants.

Taking this valuable data to their next school project, Dr. Martin Luther King Jr. School in Cambridge, Massachusetts, Perkins Eastman reduced the window sizing and added an internal lightshelf to improve daylight distribution while minimizing glare.

Photos courtesy of Perkins Eastman

In Perkin Eastman’s POE for Dr. Martin Luther King Jr. School, 82 percent of the school staff reported satisfaction with the glare and visual comfort in the new school as compared to old swing spaces.

“Designing these classrooms to meet lower daylight targets actually resulted in classrooms that are almost entirely daylight autonomous—many teachers have never turned the electric lights on within their classrooms per our post-occupancy evaluations, and they feel no need to pull the blinds,” reports Jauregui.

Subsequently, the team also conducted some POE work at Martin Luther King. In particular, thermal imaging revealed some important information. Firstly, the storefront doors were significantly underperforming the rest of the storefront system and were a major contributor to heat loss in the winter.

“This information not only helped us report back to the manufacturer and discuss possible improvements that could be made to the product, but it also helped the design team realize the impact that expansive amounts of storefront doors could have on energy performance and limit that moving forward,” Jauregui explains.

Secondly, thermal imaging revealed that during installation, many of the inside corners on the project were left uninsulated as the corner detailing was not properly followed. “Through conversations with the contractor, we determined that the insulation was only installed directly behind the outside face of the brick, leaving a square gap at the inside corners,” she says. “This information has helped us to have specific conversations with the contractor and subcontractors to fix the existing problem and to ensure that future projects do not have this issue.”

Also using diagnostic equipment, in this case a solar radiation meter, part of Kirksy’s POE for Energy Center Three, a Houston headquarters building, measured the SHGC at select locations inside the curtain wall building with an approximate window-to-wall area ratio of 67 percent. In particular, the team took measurements on the east-facing, third-floor balcony where the low-E, double-glazed curtain wall windows were found to be performing in line with their manufactured value of 0.22.

Image courtesy of Kirksey Architects

As part of Kirsky’s POE for Energy Center One, the single-glazed balcony windows were found to be performing at their SHGC published value of 0.82, but the doors were only performing at 0.42. Although this was actually the doors’ SHGC published value, the discrepancy between the thermal performance levels was only realized through the POE.

When the team measured the single-glazed balcony doors, they were also found to be performing at their SHGC published value of 0.82, but in actually studying the doors in comparison to the windows, the design team realized a discrepancy between the thermal performance levels.

“After our POE measurements, we made inquiries and found that using high-performance double glazing in exterior doors is an available, custom option with extra expense. We now know to consider this and build in the cost on future projects when called for,” relates Hendricks.

Trammell Crow was very supportive of Kirksy’s efforts to study the building post-construction because it allowed the company to relay valuable information during its sale to Conoco Phillips. “They were happy to report that the building was working as designed,” Hendricks says.

Looking at another noteworthy POE study, HGA revisited its design for the Los Angeles Harbor College Science Complex, a three-story, 73,767-square-foot complex using approximately 43 percent less energy than baseline models and producing about 26 percent of its own electricity from solar panels.

The high-performance LEED Platinum design features integrated photovoltaic panels connected to the campus PV systems, occupancy-sensor lighting, extensive exterior shading, natural ventilation, abundant daylight, integrated building systems that respond to weather conditions, and an energy-recovery system that converts exhaust air into energy.

HGA’s POE evaluated the project’s performance in terms of general satisfaction, thermal comfort, acoustical quality, air quality, and lighting. Based on positive user feedback, HGA is using this project as a catalyst for further projects, specifically in the higher education realm.

“We are using takeaways from this project for two higher-education science buildings in California, in addition to an office project. In these new projects, the team is really enforcing a uniform distribution of lighting in the design so every surface in the room has an even amount of light, avoiding dark spots within the space,” reports Thibaudeau.

For another project, Intermountain Healthcare brought in Building Envelope Commissioning (BECx) expertise for its Utah Valley Clinic in Provo, Utah, to both assist with the design and construction of the building enclosure and to ensure, post-occupancy, that the envelope systems are designed, installed, and perform according to the owner’s project requirements.

Photos courtesy of HDR

At the Intermountain Healthcare Utah Valley Clinic in Provo, Utah, a building energy commissioner was brought in to ensure that the building envelope was performing as designed.

“We completed site reviews, witnessing of testing to confirm the performance has been achieved, as well as assisting with some one-off details on-site during the construction phase,” Vinci explains.

“Including a BECx as an integral part of the project was instrumental, as it was a critical process in achieving the project’s high-performance requirements as well as playing a key role in increasing the durability of the envelope while reducing risks of future envelope-performance issues,” he adds.

Why Aren’t POEs Standard Practice?

While the benefits of POEs are well-established and interest is growing, there are a number of reasons why building owners are hesitant to invest in them.

“The problem with POEs outside of a comprehensive commissioning process is the high potential for unpleasant surprises at the tail end of the building process, when corrective remediation is challenging and costly,” Patterson says. “In fact, one of the predominant reasons that a POE is often not conducted is that building owners don’t really want to know how the facade is performing.”

He notes that this is especially the case with investment properties where the owner just wants to claim a high-performance facade and “not muddy the marketing waters with reality.” Unfortunately, Patterson says that this kind of greenwashing is a common practice in the building industry, and substandard performance, resulting in excessive energy consumption, is paid for by the tenant so the owner has no motivation to make any changes.

Although owner-occupied buildings tend to present a more favorable scenario with a greater focus on data-verified performance, there are many cases where they prefer not to survey occupants out of concern for what they will say.

Furthermore, Thibaudeau points out that performing on-site evaluations and ongoing energy monitoring takes time and requires planning and budgeting. Oftentimes, such services are not included in the initial building project and are therefore an added cost that owners are typically not interested in paying.

While some owners will see value in POEs, they may not be willing to invest in external evaluation and may attempt to implement some form of POE within their own organization. However, Jauregui explains that the POE is only useful if the information can then be leveraged in a valuable way. “If there is nobody invested in processing and sharing this data internally or externally, there may be little motivation to collect it in the first place,” she adds.

Addressing the architect’s perspective in a Post-Occupancy Evaluation Survey Report where 29 members of the Architect & Design Sustainable Design Leaders network were surveyed, Julie Hiromoto, AIA, LEED AP BD+C, then with SOM and currently the director of HKS’s New York office, lists a number of reasons why design firms might not conduct a POE:

• The time and cost required to produce meaningful results
• Designer and client liability concerns
• Client privacy concerns, such as disclosing energy performance data
• Lack of client demand or interest and challenges communicating value to the client
• Lack of timely responses from the client/user
• Client desire to control or limit employee feedback
• Limited site access
• Unsuitability for certain program types such as retail
• Timing of the POE since this typically occurs after project closeout
• Lower priority of non-billable or research tasks
• Defining scope and aligning expectations of what will be evaluated
• Design team awareness and/or experience

“If the POE is not specifically requested by clients, there are clear challenges providing these type of services in competitive markets, especially if clients are comparing proposals from various potential architects,” Hiromoto says. “It is difficult to communicate the added value of this enhanced service in an RFP response.”

If the design firm does consider absorbing the costs of a POE, Hiromoto points out that it still may be difficult to execute, as POEs are typically performed 6 to 18 months post-occupancy, at which time the designers have moved on to other projects and other ongoing billable tasks take precedence at that time.

At the same time, the survey also reported more than half of the firms are currently conducting POEs and almost all would like to conduct them on a majority of their projects in the near future.

Take HDR, for example. The firm has decided that the value of POEs ultimately trumps all these issue and initiates a POE process for 10 key projects in various architectural market sectors per year. “These POEs range from simple questions regarding energy and water use to more detailed POEs involving thermal comfort and envelope performance,” reports Rohlfing.

Similarly, Hendricks relates that her firm is typically not paid to do these studies, but Kirskey has decided that POEs are in important way to help the firm improve their design process.

The Outlook for POEs

In terms of improving the usefulness and applicability of POEs, Carnes says building envelopes must be evaluated from inception to completion, not post-occupancy. “After construction is too late and during construction is too late,” he says. “During design is when the envelope needs to be evaluated, followed by construction inspection and testing upon completion.”

Another shortcoming Jauregui sees is that POEs are frequently associated with simply sending out a survey at the end of a project. “In order to fully understand building and facade performance, on-site measurements and tracking of data over time is a must,” she says. “This information cannot always be picked up in a qualitative questionnaire sent to building occupants.”

In order to drive improvement, Gowda says that better communication is key. “Also, it is important to more broadly convey that the soft costs of continuous commissioning and POEs do not exceed the long-term value add,” she adds.

Gowda points out that some of the motivation to pursue POEs is not wholly altruistic, but rather business oriented. Consequently, corporate social responsibility reporting and the adoption of various global rating systems and benchmarking ordinances that impose voluntary and mandatory policy drivers will be required to urge more POEs.

Another useful tool would be a database of POEs that architects could reference. For example, U.C. Berkley has such database of POE survey results for office buildings, but few similar resources exist for other types of buildings.

As more POEs are performed and the industry’s data collection becomes more organized, Thibaudeau is hopeful that the usefulness of these studies will improve with more information available.

Will more building owners and designs be undertaking POEs in the future? “Optimistically, I’d like to say yes,” Hendricks says.

With even more confidence, Rohlfing believes that POEs will undoubtedly gain traction, noting code changes, client requests in RFPs, and a general industry trend to verify predicted performance. Associating POE data directly with operational, health, and wellness savings could also lead to a tipping point, allowing clients to see its usefulness and applicability for future design projects.

Carnes points out that building codes requiring higher-performing building envelopes to drive down energy use are already being implemented in many jurisdictions. For example, the U.S. Army Corps of Engineers already requires testing of the thermal barrier and air barrier in all new buildings.

“With building codes continually upgrading to require increased mechanical system and overall building energy performance efficiency, building envelope performance will have to follow,” he says.

Ultimately, in the age of big data, Jauregui says that more and more people expect proof to back up statements of improvement. “You can no longer just say that your building is performing better than others; you have to be able to prove it,” she explains. “POEs provide people with the ability to put numeric justifications behind their claims, and we are already seeing an uptake of their use across the industry.”