Environmental Building NewsTM The Leading Source for Environmentally Responsible Design & Construction

A Publication of BuildingGreen, Inc. www.BuildingGreen.com Volume 23, Number 8 · August 2014

or less energy than the project team Natural Ventilation: The Nine Biggest anticipated. Most importantly, a successful natural ventilation system Obstacles and How Project Teams must be attuned to the local micro­ Are Beating Them climate and the occupants’ micro­ culture in a way that most other Designers are reinventing the art and science of passive comfort control design strategies simply don’t require. even where climate and culture favor mechanical systems. All this makes some project teams balk By Paula Melton at the idea from day one, and most never even consider it—yet even in The Eastgate building in Harare, savings to a decrease in sick days due the U.S., where climates and cultural Zimbabwe, is world-famous for its to the amount of fresh air. “Air-con- expectations typically make mechan- biomimetic passive cooling system, ditioned offices recirculate the air at ical HVAC a given, there are project inspired by termite mounds. The least six times; otherwise you waste so teams pursuing natural ventilation for fan-assisted network of thermal much energy. In my system, there is no its energy and air-quality benefits. labyrinths and chimneys cools the recirculation at all; it’s all fresh air.” space economically and “uses about Why Natural Ventilation? 10% of the energy” consumed by a As the contrast between these two mechanically conditioned building buildings demonstrates, the reasons There are three primary reasons to next door, architect Mick Pearce told for natural ventilation differ by design a building for natural ventila- EBN. project, and the system may cost more tion. or less upfront than a conventional Necessity was the mother of Pearce’s mechanical system. It may save more invention. The expense of importing the equipment needed for a mechan- ical HVAC system drove the strategy. Ten years later and seven thousand miles away in Melbourne, Australia, Pearce employed natural ventila- tion again for Council House 2, with profoundly different results. That’s because the natural ventilation system pulls in air “for breathing, not for cool- ing.” Instead, radiant cooling makes the ceiling “like the roof of a cave.”

In Melbourne, the economic driver wasn’t the cost of equipment; it was worker productivity. “The building actually cost about 20% more than the cheapest office block at that time,” he said. The team expected a ten-year payback, but revised that down to seven years after a couple years of data had come in. Energy savings were actually weaker than anticipat- ed—about a 60% reduction compared Photos: Courtesy Mick Pearce

with the building it replaced, not the Similar technologies for different climates, cultures, and economies: Eastgate Center and Council House 2 85% modeled—but Pearce attributes share an architect and a strategy involving concrete thermal labyrinths, but that is where the similarity ends.

Environmental Building News • August 2014 Copyright © 2014 BuildingGreen, Inc. All rights reserved. • Energy savings can be dramatic in Viability vs. Potential climates and building types where natural ventilation is feasible for most or all of the year. Estimates vary wildly and depend on climate, but Shaun Fitzgerald, Ph.D., cofounder of natural ventilation products and consulting firm Breathing Buildings, cites savings on fan energy alone of 10% to 30% in the mild U.K. climate where he works.

• Occupant satisfaction often drives the decision in the developed world, according to many design- ers EBN spoke with. “The notion Source: Payette that you can just open a window The climate may be friendly to natural ventilation, but the microclimate and other factors can reduce the potential significantly. and hear a bird chirp or feel a little breeze is psychologically very refreshing,” notes Steve Tatge, a Kita Schloss-Geister, that has been natural ventilation viability—based lead architect at the University mostly successful but also problem- simply on the local climate—and of Washington, which is pioneer- atic; his firm helped the architects natural ventilation potential—based on ing natural ventilation strategies fine-tune the daylighting scheme for the site, microclimate, and other finer in a number of new and existing the design, which initially was over- details (see chart). After the topic is in- buildings. glazed, in Marais’s judgment. “LEED troduced and vetted based on viability, was the number one priority,” so day- the second set of calculations guides • Indoor air quality is closely related lighting was “very heavily weighted. whether the project should be natural- to occupant satisfaction. “If you can At that stage, I don’t think anyone was ly ventilated, mixed mode (a combina- introduce copious amounts of fresh giving natural ventilation a thought.” tion of mechanical and passive strat- air without using fans, you’ve cre- egies), or mechanically conditioned ated an amazing environment for By the time the firm had turned its year-round. If the system will involve the people inside,” says Fitzgerald. attention to ventilation, they discov- sensors or automation sequences for In some climates, he remarks, ered certain windows were too large: windows, fans, or other components, “About 70% of the year, the idea of “Even if you just opened them a little it’s best to discuss that early in design being cocooned in a glass box that’s bit, there was a lot of air”—a problem as well, Menchaca cautions, because air-conditioned is just anathema.” in cold weather. But it was too late these will need to be budgeted for. to change the windows; as a work- The list of reasons not to attempt natu- around, some rooms in the finished Engineering good relationships ral ventilation is considerably longer, building have to be ventilated while but experts EBN spoke with have dis- the children and teachers are else- Even if the client is convinced, the covered that many of these obstacles where in the building. mechanical engineer may not be. have a lot more to do with perception “They want to avoid liability and and habit than with physics. We’ll ex- How early? risk,” says Blake Jackson, AIA, of plore nine of these barriers, and how Tsoi/Kobus. “You really have to get project teams are overcoming them. “What we do is assist the teams in the them on board.” (See #2 below for very, very early design stages, guiding more on the perceived risks of natural 1. Conventional Design them toward more efficient choices in ventilation.) Process terms of design,” explains Alejandra Menchaca, Ph.D., one of two in-house It helps when architects educate them- “The architect wants to sell a proj- building scientists at Payette. Their selves, Jackson suggests. “You have ect with good-looking pictures,” guidance compares options for orien- to have a few factors working togeth- argues Jean Marais, B.Eng., of the tation, massing, and shading to inform er and a team that’s in agreement,” Berlin-based engineering firm decisions about daylighting, natural including architects who understand b.i.g. bechtold. “There is a lot of glass, ventilation, and other strategies. how building geometry, ceiling height, and the fenestration is not always glazing, and other features affect the effectively used.” When considering natural ventila- feasibility of the scheme. “There’s tion, the “first step is to evaluate the nothing keeping architects from Marais relates the story of a 7,000 ft2 climate,” but it doesn’t end there. picking up the CIBSE guidebook,” he naturally ventilated daycare center, Menchaca draws a distinction between says (CIBSE is the U.K. equivalent of

Environmental Building News • August 2014 p. 2 ASHRAE; AM10 is its natural ven- it took me three days to get the right do. Somehow, we’re okay with that.” tilation standard, and AM13 covers settings.” That said, she admits, “I have seen mixed-mode ventilation). “It’s rela- so many buildings where the natural tively visual, considering it’s an engi- That situation may be improving ventilation doesn’t work,” whether neering tool.” soon, reports Philip Haves, Ph.D., because of the design itself or because leader of the simulation research “everything was properly designed, No supermodels group at Lawrence Berkeley National and then the control systems failed.” Laboratory (LBNL). A team of re- Control systems can be re-sequenced Ideally, the project team would be able searchers led by Paul Linden, Ph.D., (more on this below), but if the system to provide a rough sense of energy chair of the Department of Mechanical doesn’t provide enough airflow, or if savings early on, but “the decision to and Aerospace Engineering at the occupants are not comfortable enough use natural ventilation or not comes University of California–San Diego or not flexible enough, “you can’t just way before we have a full building en- has developed new models of vari- ‘fix’ your occupants. All you can do is ergy model,” says Menchaca. “Many ous modes of natural ventilation, and reduce the amount of natural ventila- times, we don’t have the answer other LBNL has been integrating these new tion that you’re using.” than knowing the climate outside is models into EnergyPlus. One of the nice.” models, he explains, deals with eddies Most buildings in the U.S. make that form against buildings and can this possible by installing a backup Menchaca calculates roughly what cause “pumping action” that either mechanical system that’s already percentage of the time the building draws wind in through the window being used for a certain percentage of will be using natural ventilation and or forces interior air out in hard-to- the year, with natural ventilation re- creates a spreadsheet showing “how predict ways. When released, these served for “shoulder seasons.” Before that translates into energy, depending new models will help teams “design resorting to the mechanical system on the HVAC system.” As the design for single-sided ventilation with more more often, consider creative strate- advances, these calculations of sav- confidence,” which Haves says is key gies for correcting the natural ventila- ings get better, but not as much as one to encouraging adoption of natural tion scheme. might hope. “I wish energy modeling ventilation. tools would do a better job of mod- Your biggest fan eling natural ventilation,” Menchaca 2. Perceived laments. “I’ve spent a lot of time Menchaca spent four years of her trying to get the right flow rate that Unpredictability graduate work helping design the I knew my math was giving me, and “So-called experts will tell you nat- ten-story HULIC Co. Ltd. head­ ural ventilation won’t work. What quarters in Tokyo. It has vents rather they really mean is that they don’t than operable windows, and a com- understand it,” maintains Leon plex automation sequence. When the Glicksman, Ph.D., professor of building opened, “people hated it,” building technology and mechanical Menchaca confessed. Everyone was engineering at the Massachusetts cold all the time. The project team dis- Institute of Technology (MIT). covered a flaw in the sequence, “one loophole that would never turn the fan Fear of being stuck with a system that off. It was just fixing that one bug, and doesn’t work can be a huge barrier to now people love it.” Stick around after natural ventilation. “The gold stan- the building is occupied, she cautions. dard for mechanical engineers is 80% Otherwise, “if it fails once, people will of the people comfortable 80% of the close the windows and never use it time,” adds Tatge. “This presumption again.” of ‘air-conditioning equals univer- Your latest fan sal comfort’ is a false one, but it’s power­ful.” Those fears aren’t entirely unfounded, though. Facility personnel Glicksman pointed to the opposite “like to be able to do something, turn a problem in the Boston Artists for dial” when they get a complaint, says Humanity building, which relies on Tatge. “There’s less ability to do that night flushing and exposed thermal in a naturally ventilated building. You mass for cooling in summer. “There’s a Photo: Hulic Co. Ltd. can’t turn it down. It is what it is.” crucial problem that we’ve confirmed” For safety reasons, the Nikken Sekkei-designed after monitoring, he said. “Occupants Hulic headquarters in Tokyo features louvered air can turn on fans at night and set them intakes, seen here, instead of operable windows. A Adds Menchaca, “We’re convinced faulty computer sequence had occupants shivering that mechanical systems work the for a certain number of hours, but when the building first opened, but a simple way we design them—and they rarely there were no real operating rules. In debugging process solved the problem. most cases, they didn’t turn them on

Environmental Building News • August 2014 p. 3 long enough,” waiting till midnight associate at Arup rather than starting the fans at 8 p.m. in San Francisco. His team at MIT is now researching He urges project “some fairly simple design and oper- teams to recognize ating rules to help manage” natural the importance of ventilation. communication with all stakeholders A chilling tale during design and occupancy. The design team for the University of Washington (UW) Molecular “Passive is a Engineering Building got an earful misnomer” in post-occupancy evaluations about the naturally ventilated office wing of One thing that prob- the building being chilly in summer. ably doesn’t get com- “The challenge is keeping people municated enough is Photo: Public Domain from being too cold while effectively that natural venti- cooling the mass” at night, explains lation depends on Adaptive thermal comfort means people can tolerate a wider temperature range if they control their clothing and environment—for example, by Chris Chatto, Assoc. AIA, principal occupants taking listening to President Jimmy Carter and donning a sweater. But culture at ZGF. “Usually this is most extreme responsibility for matters: some Americans balked at the idea of layering instead of turning in the mornings.” Further analysis their own comfort, up the thermostat. also revealed that graduate students as attested to by were staying late in the evenings, Michael Henry, P.E., control features will be happier in a well after window actuators had been AIA, of Watson & Henry Associates, naturally ventilated space. programmed to begin night flush- a firm specializing in historic pres- ing. “This was addressed by pushing ervation. “I approach it by trying to Meanwhile, though you can’t please back the start of this sequence.” (See understand the building as an active all of the people all of the time, you Post-Occupancy Evaluations: Igno- envelope,” he explains. “I tend to stay can design to mitigate temperature rance Isn’t Bliss.) away from the word ‘passive’ because swings and minimize cold drafts. historic buildings require occupant Putting walls to work Modus operandi interaction.”

Marais relates that interactions with The cultural barriers to this way of Peter Alspach, P.E., associate principal radiant cooling or heating systems thinking are formidable. Points out at Arup in Seattle, tells EBN that some can also be flawed. “One of the things Jackson, “We relied on [natural ven- naturally ventilated buildings appear that they could have done better is to tilation] solely, no matter where you to “out-perform the thermal models change the way the radiant floor is were, for eons and eons up until the we have of them.” controlled,” he told EBN, referring to 20th century. Suddenly we have the Kita Schloss-Geister. Because the day- ability to shut up our buildings and Although he hasn’t been able to con- care center is currently regulated by completely control the environment, firm with empirical data, he suspects an air thermostat, when teachers open and codes and rules and expectations this might have something to do with the window to ventilate, “right away, evolved around that. It’s hard to take high thermal mass, most notably in the radiant floor tries to heat up the a step back in the opposite direction.” historic buildings. At Clark Hall at room as fast as it can,” an undesirable Success, he says relies on occupants the University of Washington, built in feedback loop. The building owner who “take control of their own level of 1896 and renovated in 2009, comfort will likely be retrofitting with a radiant comfort.” models suggested the space might get thermostat. as warm as 82ºF (28ºC) on the hottest Indeed, the psychology of comfort summer days, but actual measure- 3. Comfort Issues has much to do with control; the more ments on a sunny, windless 85ºF day control each occupant has, the more showed readings of 78ºF (26ºC) in the The best fix of all is the one you don’t comfortable each will be (see Adaptive building. “The way mass lulls perform have to do. Experts emphasize that Thermal Comfort). But the same dynamically is not well captured in stakeholder groups need to under- things that can make a natural ventila- the simulation tools,” he says. “There’s stand what a natural ventilation tion scheme successful—namely, open a fear I have that we could do a lot system really means before they adopt offices and automation—can compro- more natural ventilation and have it. “A lot of times, the people who mise that control. Occupants with a acceptable performance than we do” make the decisions on the client side flexible dress code, flexible attitudes, but that we let our simulation tools aren’t the people who sit around and and the ability to adjust shades, ceiling talk us out of it. use it” argues Paul Switenki, P.E., fans, desk fans, and other comfort-

Environmental Building News • August 2014 p. 4 seldom used and may be ineffectual for ventilation. Where costs get added

A system that includes the following may add to the cost of the building or its operation:

• CFD modeling reduces risk and is a wise investment for projects that rely on natural air flows, but it requires paying a specialist.

• Controls like window and vent actuators, “stop-light” systems, oc- cupancy sensors, and other equip- ment might eat into the savings of not having a mechanical system.

Photo: Breathing Buildings Ltd. • Operable windows usually cost Though it pushes the boundaries of what might be considered “natural” ventilation, the Breathing more—and some insurers might Buildings system provides fresh air year-round in a way the company claims solves the problem of the not like them, leading to increased cold draft. With the Monkseaton school, the ventilation shafts were made into a colorful exterior design feature. premiums.

Chatto says ZGF has used phase- such a system would work in humid • A narrow floorplate means higher change materials to perform the same climates. costs due to greater surface area function as thermal mass on projects that must be designed and built. where exposed masonry or concrete A simpler method of mitigating cold Any project that’s providing day- isn’t possible or desirable. drafts can be seen in the historic lighting and views may already be Joseph Vance Building (see below). paying these same costs, however. Evading the draft 4. Cost • Mixed-mode systems are the In warm weather, a breeze is refresh- greatest potential expense; the ing and aids evaporative cooling. In The first cost of natural ventilation will mechanical system, even if it’s just buildings that rely on natural ventila- vary depending on how it’s designed, a backup, will still have to be de- tion in winter, that “breeze” becomes and return on the investment will signed for peak heating and cool- a draft. Shaun Fitzgerald of Breathing vary depending on how it’s designed ing loads—the very times when Buildings claims his proprietary as well as how it’s used. Clients may natural ventilation isn’t feasible. ventilation system has “cured a cold lose heart when they realize they need Cost savings draft using heat loads within a build- a fully functional mechanical system ing” rather than relying on perimeter alongside the natural ventilation radiators, which “uses bucketloads of scheme, notes Alspach. “Why not just The following may yield savings on heating energy. You can halve your pay for the mechanical system and call first costs or during operation: heating and fan bills if you’re smart.” it a day?” For some clients, the desire • Less equipment will be needed if for occupant comfort and satisfaction the building can be naturally venti- With this technology—which many will win out, and for others, the ener- lated year-round. would argue is more like heat­- gy savings may make the difference. recovery ventilation than natural • Doubling up with other systems ventilation—a ceiling fan draws Because of the narrow footprint will decrease the effective cost of outdoor air into stack vents, where a needed for adequate ventilation using designing and constructing for nat- second ceiling fan mixes it with rising operable windows, deciding whether ural ventilation. “One of the best air that’s been heated by internal to attempt natural ventilation needs to things you can do for the building loads from occupants, computers, and begin before many other decisions can is daylight well,” says Duncan solar gain; the company claims no be made, notes Jackson. “You can’t just Phillips, Ph.D., P.Eng., principal extra heating is needed until outdoor shut down if it gets too hot indoors.” at RWDI (see Doing Daylighting temperatures are below 41ºF (5ºC). In Because of this dilemma, he says most Right.) “If you daylight well, you summer, windows are opened, and the owners choose to design for mechan- have a much, much better chance fans draw warm air out through the ical ventilation—which often results of naturally ventilating.” The same stack vents. It’s unclear how well in a large floorplate for efficiency— thermal mass needed to maximize and add operable windows that are

Environmental Building News • August 2014 p. 5 the effectiveness of passive solar ventilation) provided to some occu- and “ghosts of operable hardware” to (see Passive Solar Heating) also pants, or controls that can automatical- help him puzzle out just how build- complements natural ventilation ly turn off the HVAC system in offices ing systems have been designed and by increasing the effectiveness of with open windows. operated. “Expect an unexpected level night flushing. And although there of sophistication and complexity,” he are safety issues with some natural Earlier structures, even those built advises. “These folks really knew what ventilation strategies (air pathways after the introduction of mechanical they were doing.” are also smoke pathways), others air conditioning, were likely designed synergize with fire codes, notes with daylighting in mind—sometimes The restored 14-story Joseph Vance Menchaca. “If you are using it in an natural ventilation as well. Restoring building in Seattle, completed in 1929, atrium that already has to have a the natural ventilation system in such provides a celebrated example. As smoke evacuation system, you are buildings may be possible, depending the project team toured the building using what you already built; there on fire codes and security concerns. discussing renovation options that is no question about cost because included full façade upgrades and “The historic building envelope was you are already spending on it.” window replacements, Arup’s Alspach really a thing of marvelous complex- noticed that “some spaces had little • Economizer mode, sometimes ity,” argues Michael Henry. “Much window deflectors,”—hardware the called “free cooling,” is one way to of that took place through the win- owners viewed as “obnoxious.” But “sneak” natural ventilation into a dows.” The trick, he says, is to do he noticed that the deflectors actu- mechanically conditioned building. some “archeology” to discover how ally have a purpose. In winter, they “It brings air in through the ducts the building was meant to work so keep cold air from slightly cracked but doesn’t condition it,” Menchaca that the many functions of windows, windows from entering the room as explains. Designing the mechan- light shafts, and other features can be a cold draft; in summer, they direct ical system to utilize economizer fully restored. “What we find today is air upward to prevent breezes from mode as much as possible can save just a portion of the original technol- blowing papers off desks. significantly on energy. ogy,” such as ventilation shafts that have since been filled with elevators or The project ended up not having the • Other energy savings come ducts, or operable skylights that have budget for window replacement, but through more obvious means: been sealed. “Cupolas are not there for natural ventilation—including the turning off the mechanical system decoration; they are for environmental deflectors—lives on in the building, and relying on wind, stack effect, management.” supplemented by light shelves with or fans to bring in fresh air. Even if built-in fabric shades for light control. this is only possible for a third or a Restoring full functionality takes As tenants leave, air-conditioning quarter of the year, that’s a third or more than re-opening operable units are removed from the vacated a quarter less energy the mechani- windows, though, Henry warns. He space, and a tenant guide developed cal system is using annually. has used old ASHRAE journals and by ZGF and Arup helps the new handbooks, blueprints, photographs tenants plan their fit-outs to maximize 5. Built-In Limitations showing closed shutters in summer, natural ventilation and daylighting. Depending on the climate, wind-driven or buoyancy-induced ventilation may require a certain ori- entation, geometry, interior layout, or site master plan. What if one or more of these factors is out of your control? Some existing buildings may simply be inappropriate for natural ventila- tion, but experts EBN spoke with say not to give up immediately.

Many commercial buildings, par- ticularly built from the 1950s to the 1990s, do not lend themselves to daylighting or natural ventilation due to deep floor plates. Some of these may be retrofitted by the introduction of an atrium. Others may be able to Photos: Joe Mabel (L), license CC-BY-SA 3.0. © Arup (R), used with permission. use the free cooling provided by the The historic Vance building in Seattle includes original ventilation deflectors (bottom of window) designed HVAC system’s economizer mode, to prevent drafts and disruptive breezes. Restoration efforts also included installation of ceiling fans and light shelves with built-in fabric shades. with operable windows (single-sided

Environmental Building News • August 2014 p. 6 scale cultural changes, there are other options, such as desiccant-based de­ humidification or even, suggests Mick Pearce, water curtains chilled using solar thermal cooling; at around 12ºC (54ºF), the waterfall draws humidity from the air by causing condensation.

Phillips cautions that the system must be designed carefully to avoid add- ing water droplets back to the indoor environment in an unwanted feedback loop. Natural ventilation and climate change

As the global climate changes, the number of days of the year when nat- ural ventilation is practical will likely decrease in many places (see Design- Photo © Peter Vanderwarker ing for the Next Century’s Weather). The Gary C. Comer Geochemistry Building at Columbia University features natural ventilation in its The effect is amplified by humidity, office wing; Payette designers took advantage of natural shading omfr existing trees to keep the building cooler. notes Cole Roberts, P.E., associate principal at Arup in San Francisco, pointing out that heat-index calcula- natural ventilation. All the familiar 6. Heat & Humidity tions are non-linear, so small shifts in strategies for cooling the building’s temperature cause much greater shifts Given the ability to adapt their cloth- microclimate—shading of paved in discomfort: at 80ºF and 80% rela- ing, airflow, lighting, and other aspects areas, landscaping in place of pave- tive humidity, for example, the heat of their environment, humans can ment, vegetated or cool roofs, and a index is a tolerable 84ºF, but 82ºF at tolerate a wider range of temperatures high-reflectance façade—will keep the same humidity comes out to a heat than they can if they have no control— temperatures cooler and allow win- index of 89ºF. “The industry could be but there are limits. “If the outdoor dows to remain open longer. temperature is 90ºF, you’re bringing in communicating better” with clients air that’s 90ºF,” Jackson states. “Once Dry heat, wet heat about such effects, Roberts argues. He you get beyond a certain threshold, all and others at Arup have developed you’re doing is introducing heat.” Part of the problem in many U.S. a software tool called WeatherShift climates, Menchaca adds, is the hu- to help them do just that (see Tuning Stay out of the kitchen? midity. “If it were dryer, you could use Today’s Building Designs to Tomor- evaporative cooling,” she explains. “If row’s Climate). The classic way of mitigating these you’re in Boston, you can’t humidify The data so far have led Roberts to effects—exposed thermal mass (or because it’s already at 90%” on some sound the alarm about natural ventila- phase-change materials) and night days. flushing—have already been men- tion: “There’s a commonly held belief tioned, but there are some less obvi- “We can’t take humidity out of the that naturally ventilated building ous strategies for preventing over- space, but we can increase air move- stock is a responsible course moving heating as well. “Shade like crazy,” ment,” notes Phillips, who has worked forward because of all the mitigation offers Duncan Phillips, Ph.D., P.Eng., in regions where natural ventilation benefits and savings on greenhouse principal at RWDI—but never at the is a given regardless of the outdoor gases,” but that “may not be as sound expense of wind-flow, he cautions, conditions. It helps that the impact of an approach as perhaps the indus- because feeling airflow over your skin air movement actually increases with try has thought” due to increases in is psychologically just as important humidity: “If we blow air over you average temperatures, heat waves, as the evaporative cooling the airflow and you perceive air movement, your and overnight temperatures. provides. body will feel cooler.” He’s seen this On the other hand, he adds, “If you strategy used effectively in Singapore, look at resilience from the standpoint Additionally, preventing urban heat Shanghai, and Malaysia, he says. islands doesn’t just make you a good of power outages and passive surviv- neighbor; it also makes it easier to Americans are less likely to accept ability, natural ventilation is brilliant.” keep your own building cool through such conditions, so barring large- Operable windows may not save enough energy to prevent climate

Environmental Building News • August 2014 p. 7 Natural Ventilation and Climate Change laments Phillip Haves at LBNL. “It’s not Beijing,” he jokes, referring to China’s notoriously polluted air, but sensitive people should be closing the windows when smog and particulate levels are high. 8. Acoustics Outdoor air quality often goes hand in hand with acoustical issues. ZGF addressed both problems with the UW Molecular Science Building by re-orienting the original design to have the naturally ventilated offices face a courtyard rather than the street. “The eastern façade was going to be [mechanically conditioned] labs facing the quieter courtyard, and the office view would be of downtown Seattle and the water,” explained Chatto. That got turned around when natural ventilation came into the discussion because of the noise and pollution from trucks and buses—and to pre- venting overheating of the naturally ventilated offices from afternoon sun.

Acoustics inside the building may be more problematic (see Building Green ... Quietly: Noise Pollution and What to Do About It). Open layouts are desirable to maximize air circulation but can disrupt acoustical privacy, and exposed thermal mass can cause unwanted reverberation. Chatto says

Source: Arup and Argos Analytics at UW, the team compromised by adding carpet and using phase-change In a twist, this San Francisco area building’s natural ventilation potential could increase with warming materials behind drywall. temperatures, according to Arup’s WeatherShift tool. Open-office layouts are well known to change, but in a hotter world, they can really a question of geometry, even in come with acoustical issues, so follow make buildings more tolerable to be in urban environments” says Jackson. best practices to ensure that occupants when the power goes out; many firms “There are ways to make the wind have a refuge for meetings and private now view them as a key resilience work to your will. You just have to phone calls (see Open Offices Engen- feature regardless of the mechanical bend the building.” der Collaborative, Transparent Work- system. places). On bad-air days in some areas, win- 7. Outdoor Air Quality dows and vents may simply need to be closed to protect those with asthma 9. Fear of Human Error Natural ventilation is touted for or other health issues. Fortunately, Busted pipes, rained-on equipment, providing high indoor air quality— these days will typically coincide with first-floor break-ins, and heat escap- but is unfiltered outdoor air really an the hottest and most humid ones, ing over the winter holidays as fast improvement? when mechanical backup would be as the radiator can produce it: all are likely anyway—but this restriction nightmare scenarios that may come up Not always, but there are usually ways does limit the ability to implement when discussing natural ventilation to handle it, starting with orientation pure natural ventilation in some with clients. They are far less likely that points naturally ventilated areas climates that would normally allow to come true when the integrative away from major highways or other it. “California’s been challenged for process includes the right stakeholders sources of outdoor pollutants. “It’s all a long time with poor air quality,” and continues during occupancy. The

Environmental Building News • August 2014 p. 8 more pressing threat, as Menchaca A matter of trust sees it, is from occupants not under- standing when it’s okay to open their Like window windows—resulting in less energy actuators, occu- savings than projected, or in natural pants aren’t 100% ventilation never being used at all. reliable—and unlike actuators, “Occupant behavior is at least half of they can’t be com- the chance that your system will work missioned. “One or will fail,” cautions Menchaca. “We of the big social spend a lot of time thinking about how things is that, we can make the occupants comfort- even if you give able and help them understand how occupants red the system works.” and green lights, they might not be All the ways of getting around this— too interested or whether by engaging occupants or by eager to act, and trying to leave the potential for human they don’t see it error out of the design—have their as a reasonable pitfalls. responsibili- This little light of mine ty,” says Paul Switenki. “Our Window sensors with indicator lights success stories are are a popular way to show occupants tied to informing that conditions are right for opening the occupants and Photo: Tsoi/Kobus windows, based on exterior tempera- teaching them ture or interior CO levels. But they’re how the system Boston College provides operable windows to professors to increase their 2 comfort and satisfaction, but if those absent-minded professors leave not foolproof; occupants may simply works.” windows open it’s a potentially expensive mistake, says Blake Jackson at ignore the lights. Tsoi/Kobus. Natural ventilation requires diligence and trust as well as That can certainly good design and engineering. In particular, Menchaca says, they can feel risky, and be a poor choice in schools. “You have some owners “Come Back and Make multiple occupants, but the one occu- won’t be willing to take that risk. Sure” pant you’re relying on is teaching the Jackson tells the story of a 300-year- entire time.” In this case, the windows old building where occupants had If there’s one theme we heard over could be automated, or the school to open windows for ventilation in and over again, it’s that the success of could choose to teach the students to winter—which one day resulted in a natural ventilation scheme is tied to open and close the windows at the “a million-dollar pipe-break fiasco.” continued engagement after people right time. Though such incidents are rare, the have moved in. specter of them can be a deal-breaker. Operator, could you help me place “We haven’t been able to do [natural “You need to have someone come back this sash? ventilation] simply because of people’s and make sure the system is working,” past experiences with really intelligent argues Menchaca. This is particularly Automated window, vent, and shade people who can’t remember to close true with more complex systems, such operators are also a mixed bag. As their windows,” says Jackson. as those with automated components mentioned above, automation reduces or sensors. “It’s giving a poor name adaptive comfort options. “When Yet some occupant groups are an to natural ventilation when actually people control their environment and ideal match for operable windows it’s the mechanical system that’s not have access to the outdoors, they are and the responsibility they entail, as working,” she says, but too often, the more likely to be comfortable,” says Peter Alspach describes with Clark passive design takes the fall, and all Jackson. “If you take the operation out Hall at UW. The university expressed the team’s hard work goes to waste. of their hands, it’s basically doing the concerns about security, but they had “With natural ventilation, the easy fix same thing a mechanical system does. reckoned without the building’s occu- is to just close the windows”—and You would have to design on a more pants: the ROTC program. “The user they might never be opened again, stringent temperature requirement group solved it,” beamed Alspach. resulting in a loss not only in building inside.” “They just said, ‘This is the policy, and performance but also for the industry everyone needs to learn how to use as a whole. the building.’”

Environmental Building News • August 2014 p. 9 FROM THE EDITORS with natural environments and supports biodiversity. The practice of Architectural Board Should Sustainable Design has, over the past Reinstate Sustainability decade, become increasingly focused Criteria on integrating human health and well- ness into our design thinking. Human Collaboration skills and health is entirely dependent on the sustainability concepts health of the planet; we are all part of are being “elevated” by the same ecosystem. Our clients in- the National Architectural creasingly understand this perspective Accrediting Board (NAAB)— and see the benefits for our buildings’ but it’s really a demotion. occupants and the environment as a whole. By Nadav Malin Photo: Mark Piepkorn Realm A: Critical Thinking and The National Architectural Accrediting Nadav Malin, BuildingGreen President Representation Board (NAAB) is updating the crite- ria it uses to accredit degree-granting We encourage you to take a look and II.1.1.A. Critical Thinking and architecture schools in the U.S. It is consider submitting your own com- Representation. Given the critical role accepting comments on the “First ments to [email protected]. of design to drive performance, we Reading” of its criteria through June recommend the addition of a specific 24, 2014. Here’s the full text of our requirement that graduates be able to demonstrate understanding of the BuildingGreen is concerned about comments to NAAB relationship between built and natu- some of these changes and has sub- June 24, 2014 ral environments, and the ability to mitted the following comments, which incorporate environmental and human are similar to positions taken by the Dear NAAB Directors, health considerations into their work. Society of Building Science Educators This recommendation is consistent (SBSE) and Architecture 2030, and As a leading provider of knowledge with the AIA requirement that envi- which follow closely a letter endorsed resources to architecture schools and ronmental performance be included by three-dozen leading architecture design firms, BuildingGreen pays as part of the design criteria for all firms. close attention to the transition young national Honor Awards: great design designers make from education must perform well. Elevation in name only to practice. From that perspective, we strongly support the Defining Realm B: Building Practices, The gist of these comments is that Perspectives included in the First Technical Skills, and Knowledge key aspects of architecture education Reading. We are concerned, however, relating to collaboration skills and sus- that including environmental steward- II.1.1.B.2. Site Design: We appreciate tainability have been “elevated” from ship and collaboration skills among the considerations listed and recom- specific requirements to “Defining these Defining Perspectives without mend adding an understanding of Perspectives.” While NAAB may con- clearly defined “abilities” that gradu- protecting and nurturing habitat for sider that a promotion, many educa- ates are expected to have will do little other species. tors attest that those Perspectives get to ensure that the next generation of little more than lip service during ac- architects enters the profession with II.1.1.B.6. Environmental Systems: creditation reviews, while the Criteria the skills that firms are looking for. Experience in practice has demonstrat- are followed closely. ed the essential role of the architect To address this shortcoming in the first in integrating environmental perfor- We’re advocating reinstating some reading, we offer the following recom- mance into design from the earliest of the Criteria that were deleted and mendations: phases. Passive solutions provide the reframing and clarifying a few points Defining Principles means to meet performance goals as along the way. One notable point is part of an overall design solution. the direction NAAB is taking on inte- I.1.4.A. Stewardship of the Graduates should have the ability grative design—making it more about to use tools for early whole-building Environment. We strongly support the integrating innovative ideas, not about energy modeling, envelope and mass- Environmental Stewardship Defining the kind of team-oriented process that ing studies, and daylighting studies Perspective but recommend that it be LEED and leading professionals in the as part of an iterative design. A deep reframed in more positive terms by field have pushed for. understanding of how to apply, not including design for human health just have an understanding of, these and wellness, and creation of a built environment that exists in harmony

Environmental Building News • August 2014 p. 10 ideas should be an essential part of an performance simulation and the capa- building-based greenhouse gas emis- architectural education. bility to meet carbon-emission reduc- sions 30% by 2017 has already brought tion targets. success stories to fruition and has II.1.1.B.8. Building Materials developed into an expanding pro- and Assemblies: The impact of Respectfully, gram for commercial and multifamily architectural materials decisions— buildings. from external structure to envelope to Nadav Malin, President finishes—is increasingly important as Six universities and hospitals have met BuildingGreen, Inc. we recognize building materials’ im- the goal, cutting annual emissions by pacts on human health, wellness, and 148,842 metric tons of carbon. The ear- the environment. This principle en- ly achievers are Barnard College, Fash- compasses the human health and well- NEWS ion Institute of Technology, New York ness impacts of materials, full life-cy- University, The Rockefeller University, cle environmental assessments, carbon NYC Carbon Challenge New York Hospital Queens, and Weill footprint of materials, and biodiversity Makes Headway in the Cornell Medical College. If the rest of impacts. A focus on materials trans- Private Sector current participants also meet their parency is now a priority for many goals, the program is projected to leading architectural firms and a core With projects meeting New reduce citywide emissions by nearly priority within the AIA (see www.aia. York’s steep goal of 30% less 600,000 metric tons of carbon dioxide org/materials), and there is a growing carbon ahead of schedule, equivalent—more than 1% of total focus of research and tools develop- the city calls on even more citywide emissions. ment on the environmental and health buildings to take on the Strategies from the early adopters impacts of materials. A qualified challenge. architectural education should result in the ability to apply concepts and By Candace Pearson Those who have achieved the targets use environmental-impact assessment implemented similar deep retrofit tools throughout the design process. New York City’s Carbon Challenge is strategies, which often included phas- proving that one of the most effective ing out fuel oil, according to the “New Realm C: Integrated Architectural ways to get the biggest energy hogs to York City Mayor’s Carbon Challenge Solutions cut their carbon emissions is simply to Progress Report,” as well pursuing ask. lower-hanging fruit like lighting II.1.1.C.1. Integrative Design: As upgrades, retrocommissioning of What began as a request from May- formalized by the ANSI Integrative building equipment, and improved or Michael Bloomberg for univer- Process Standard, “ANSI Consensus operations and maintenance. sities and hospitals to match the Standard Guide 2.0 for Design and city government’s goal of reducing Construction of Sustainable Build- ings and Communities,” Integrative Design is about much more than integrating ideas, as described in the First Reading. It is fundamentally about coordinating and orchestrating a collaborative process of co-learning in which all members of a project team are supported to contribute creatively to jointly developed solutions. This is a natural implementation of the Col- laboration and Leadership Defining Perspective, and the ability to coordi- nate such a process should be added to this Criterion.

II.1.1.C.2. Evaluation and Decision Making: In keeping with the emerging needs of the profession, especially in relation to our participation in the AIA 2030 Commitment, the requirements of this criterion should specifically reference the ability to make decisions Photo: Greensulate leading to high-performance design This green roof at the Fashion Institute of Technology was one of the initiatives that helped the school reduce projects supported by whole-building its carbon emissions more than 40% in just four years.

Environmental Building News • August 2014 p. 11 In one example, New York University Changes in Dry-Bulb Temperature Through 2099 installed a 13.8 MW cogeneration plant, which reduced total energy use and enabled the switch to clean- er-burning natural gas, saving the uni- versity $11–$14 million per year. From there, the university tackled the highly energy-intensive buildings by doing massive lighting retrofits and install- ing occupancy sensors, Jenna Tatum, of New York City’s Mayor’s Office, told EBN. “Doing all that work at once made it much more cost-effective and helped achieve deeper reductions.” Most square footage for the effort

Source: Arup and Argos Analytics Laurie Kerr, previously the deputy An output generated by the WeatherShift software shows how temperatures are expected to change director for Green Building and in a location through 2099. Energy Efficiency in the New York City Mayor’s Office, toldEBN the That’s why Arup created WeatherShift, program’s strength lies in targeting Tuning Today’s Building the first modeling tool dedicated to the big institutions. That’s a particu- Designs to Tomorrow’s future-oriented building design. larly effective strategy for cities, she Climate explains, because “you capture a lot of WeatherShift was developed by square footage with one player. That A new modeling tool, Roberts along with Argos Analytics, means you can achieve deeper reduc- WeatherShift, helps designers a startup whose president, William tions more cost-efficiently than going see how designs today can Collins, Ph.D., was a lead author of the building by building.” It is also a low- account for comfort, resilience, Fifth Assessment Report just released risk chance to establish a “public-civic and energy needs decades by the International Panel on Climate relationship.” down the line. Change (better known as the IPCC— see Climate Change Fatigue? How to “All of the presidents and individ- By Paula Melton and Tristan Roberts Read the IPCC Reports). ual leaders meet with the Mayor “We need to get better at preparing and make this commitment, so it is “The spectrum of plausible for the future,” says Cole Roberts, P.E., cachet for them and cachet for the futures” city,” according to Kerr. Chicago is associate principal at Arup. also currently pursuing a program “Future-oriented design” that WeatherShift takes climate projections for its big buildings and has eliminat- accounts for a changed climate isn’t from the Fifth Assessment Report ed more than 28,000 metric tons of everyone’s cup of tea, he concedes. and applies them to decision-making carbon emissions to date, according to For example, “It’s a harder thing for for a specific building site to aid the Environmental Leader. speculative developers to get behind; burgeoning practice of future-oriented Expansion to other sectors they need to be convinced that there is design, explains Roberts. (For more on value at the point of transaction.” But modeling for climate change, see De- The New York State Energy Research it’s a no-brainer for institutions, large signing for the Next Century’s Weath- and Development Authority corporations, and urban planners. er.) Clients can choose one scenario (NYSERDA) recently funded the ex- or several to compare and get a sense And although Roberts says Arup of both optimistic and pessimistic pansion of the program to the com- has usually broached the topic with mercial and multifamily residential possibilities. “The next generation of clients, he also thinks that’s likely the software will show a range,” he sectors, hoping to extend the success to change. “They will be asking for that the challenge has so far enjoyed. A says, that will graphically unveil “the it soon if they’re not already asking spectrum of plausible futures.” “Handbook for Co-Ops and Condos” for it.” But whether they request it is now available to address the more or the design team brings it up, the Arup first used WeatherShift for a specific needs of multifamily residen- industry has to face it. Otherwise, large development project in Brazil, tial buildings. “We’re leaving ourselves open to legal where the software returned a worst- Paula Melton contributed reporting. claims” from clients whose buildings case scenario of an 8ºF–10ºF increase no longer work as expected. in the average temperature by 2080— “not peak,” Roberts reiterated, “on

Environmental Building News • August 2014 p. 12 average.” Regional architecture there Who can use WeatherShift? recommendations from experts in typically relies on a mild climate and soil science, botany and horticulture, cool breezes, but that kind of tempera- “Arup needs to get this out,” says hydrology, materials, and human ture difference could make natural Roberts. “We need to give it to other health and well-being. With its pilot ventilation impossible by century’s people. We’re designers, not data man- period over, SITES v2 is now open to end. agers.” He said Arup is looking for the public. someone who can take over develop- “How that shapes the land-use pattern ment and distribution of the applica- In addition to updates to keep up with was a lot of the conversation for the tion so everyone can use it. industry standards, notable differences project” once they’d run the numbers. between the pilot SITES System and “How do you continue to get airflow For more information: SITES v2 include the introduction of through the streets and buildings, and new credits, such as new points for what happens when people can’t use Arup Connect designating and communicating soil the same building stock when it’s that arupconnect.com protection zones in pre-design, and much warmer?” Air-cooled com- minimizing pesticide and fertilizer pressors would worsen heat islands, use during operations. A new wa- the team decided, and ultimately the SITES v2 for Sustainable ter prerequisite requires projects to project will probably rely on central- retain the precipitation volume from ized water-cooled compressors instead Landscapes Aligns with a 60th percentile precipitation event, because they perform better at higher LEED as defined by the U.S. Environmental temperatures and can more readily Protection Agency. direct excess heat for beneficial uses, Now publicly available, the according to Roberts. updated rating system features Aligned with LEED new credits and benchmarks The news isn’t all bad. Warming based on expert input. Once hailed as “LEED for Land- temperatures could reduce the need scapes,” SITES follows the same for fossil fuels in many regions. One By Beq Lendvay and Paula Melton structure as LEED, comprising pre- Bay Area client was “happy to see requisites, weighted credits, and a few The Sustainable Sites Initiative has a strong downward trend in heat- bonus points for innovation strategies rolled out its rating system for cre- ing-energy use” in addition to greater (see Group to Create Rating System ating and evaluating sustainable feasibility for natural ventilation (see for Landscapes). Now, v2 is even more landscapes. Building upon lessons Natural Ventilation: The Nine Biggest closely aligned with LEED, having learned from numerous pilot projects Obstacles and How Project Teams Are switched from using a scale of star that field-tested the 2009 SITES Rating Beating Them). ratings to LEED’s familiar four-level System, the new version features rating system: Certified, Silver, Gold, and Platinum.

The substance of SITES v2 and LEED v4 has also converged, according to Steve Benz, Hon. ASLA, partner and director of green infrastructure at the landscape architecture and urban planning firm OLIN.

“We are working LEED and SITES toward one methodology,” says Benz, who serves on the LEED Technical Advisory Group for water efficiency as well as the SITES Technical Core Committee. This is one reason the LEED “stormwater” credits have become a “rainwater” credit (see New Concepts in LEED v4) that emphasizes low-impact development and green infrastructure, he explains. “Tradition- al stormwater management has been about managing the extreme event. Ecologically, what we’re trying to do is Source: Sustainable SITES Initiative establish balance in natural systems.” The National Renewable Energy Laboratory’s (NREL) South Table Mountain campus is one of more than 100 pilot projects that field-tested the 2009 SITES rating system and one of 30 to have been certified so far. Within the two updated rating

Environmental Building News • August 2014 p. 13 systems, the “methodologies have The rule still allows HFC blowing merged,” and someday SITES may agents for spray foam because its man- even become an alternate compliance ufacture on the building site makes it path for the Sustainable Sites section unique, according to EPA. Refrigerants of LEED, he said. for building air conditioners and heat pumps are likewise not addressed in The developers are currently in the proposed rule, but the agency told negotiations with the Green Building EBN it is “interested in information Certification Institute (GBCI) to take concerning the current availability and over project certification for the new use of alternatives in other end uses rating system and to provide a related such as spray foam” during the 60-day professional credentialing program. public comment period. Pending lawsuit For more information:

The system began as a collaborative U.S. Environmental Protection Agency effort among the Lady Bird Johnson epa.gov Wildflower Center at the University of Texas–Austin (UT), the American Society of Landscape Architects Product Watchdogs Pledge (ASLA), and the United States Botanic Photo: Hemmings.com Garden, but the SITES trademark is Standardized Ingredient currently under dispute, with both HFC-134a will be banned for multiple applications, including as a propellant in aerosols, Reporting Platform ASLA and UT filing legal challeng- a refrigerant for automobile air conditioning, and es regarding ownership rights. The a blowing agent for foam insulation. A promised database funded pending lawsuit doesn’t appear to be by Google.org and USGBC affecting the release of version 2. of Insulation). EPA claims this move aims to end marketplace will prevent up to 42 million metric confusion and lower the cost of For more information: tons of carbon-equivalent emissions in ingredient disclosure. the year 2020. Sustainable Sites Initiative By Paula Melton sustainablesites.org/rating-system Specific substances to be banned include HFC-134a, commonly used Tracking potentially hazardous as the blowing agent for extruded chemicals in building products has never been easier—or more confusing, NEWSBRIEFS polystyrene (XPS) foam insulation; the compound will also no longer be per- whether you’re a designer or a man- EPA to Ban Several Common mitted in automobile air conditioning ufacturer. As interest in this informa- tion grows and the market sorts out HFC Blowing Agents, or retail food refrigeration. HFC-143a and HFC-245fa will also be banned for a confusing set of disclosure options Refrigerants production of many types of polyure- (see Finding Products for LEED v4: thane foam but still allowed in spray A Guide), clarity may be on the way. Aimed at curbing global polyurethane foam. A number of A new effort supported by the U.S. warming, a proposed rule HFCs branded by DuPont under the Green Building Council (USGBC) would ban HFC-134a, used name Formacel must also be phased through a grant from Google.org in XPS production and for out. The ban for blowing agents will will harmonize how several different refrigeration. take effect January 1, 2017, a year later programs collect and report hazard information. By Paula Melton than the bans for refrigerants and propellants. “Intuitively, we thought there was As part of President Obama’s un- Some insulation manufacturers have alignment” among systems that in- folding Climate Action Plan, the U.S. clude the Health Product Declaration, Environmental Protection Agency already begun to phase out high-GWP blowing agents in automobile and Cradle to Cradle, GreenScreen, and (EPA) has announced its intention the Living Building Challenge Declare to ban certain blowing agents and appliance insulation, replacing them with hydrofluoroolefins (HFOs) like program, explained Stacy Glass of the refrigerants. Hydrofluorocarbons Cradle to Cradle Products Innovation (HFCs) were introduced in the 1990s Honeywell’s Solstice (see New Chemi- cal to Reduce Climate Impact of Foam Institute (C2CPII). “Everyone’s gather- to replace ozone-depleting substances, ing inventories in the same way.” The but many have extremely high glob- Insulation) or proprietary blends like DuPont’s Formacel 1100. groups behind these programs, along al warming potential, or GWP (see with the Healthy Building Network, Avoiding the Global Warming Impact developer of the Pharos database,

Environmental Building News • August 2014 p. 14 worked together on a harmonization to a disaster or report for USGBC, which the new have high adaptive efforts will build on. capacity (see Proper- ty Giant Ties Cities’ The ultimate goal? A single, stream- Investment Pros- lined database that will help manufac- pects to Resilience). turers and assessors screen products Disaster-related risks and look for inherently safer alterna- for corporations tives—“to make that really hard work range from dam- of doing a chemical assessment so aged reputations much easier,” said Glass. “That’s the to disruptions in goal we jointly want to work toward,” business to increased and USGBC’s support is “getting that material costs along platform up to speed,” she added. the supply chain. The overall objective The new platform will not merge the of the R!SE initiative programs but instead help ensure that is to make all invest- they are compatible—so that a man- ments risk-sensitive, ufacturer with an HPD, for example, creating risk-resilient will have already laid the groundwork economies across the for a Declare label or the Cradle to globe. Cradle certification process rather than Image: United Nations Office for Disaster Risk Reduction producing the same information in The U.N. Office multiple ways for different programs. for Disaster Risk the 2010 standard. In a Notice of Pre- Reduction (UNISDR) is collaborat- liminary Determination posted May Glass said the database would be de- ing with the Economist Intelligence 15, the DOE has taken the first step in veloped over the next 18 months but Unit, Florida International University, issuing a ruling that will likely estab- added that the groups hoped to report AECOM and other global players on lish Standard 90.1-2013 as the commer- significant progress at Greenbuild in the initiative in an effort to facilitate a cial building reference standard for October 2014. broad approach involving business- state building energy codes. es, investors, insurance companies, DOE’s findings estimate Standard nonprofits, educational establish- 90.1-2013’s national source energy U.N. Seeks to Create ments, and government organizations. savings at about 8.5% above ASHRAE Disaster-Resilient Economies UNISDR claims it is already working 90.1-2010. In its May 15 notice in with 14 of the world’s largest corpo- with R!SE the federal register, DOE attributed rations, including Arup, ABB, and the greater energy savings to better Shapoorhi Pallonji. Helping corporations bolster lighting, fans, commercial refrigera- their defenses against the For more information: tion, boilers, and controls, which were economic effects of natural the result of improvements to the disasters is the focus of the standard, whose full name is ANSI/ new initiative. PreventionWeb preventionweb.net ASHRAE/IES Standard 90.1-2013, Energy Standard for Buildings Except By Beq Lendvay Low-Rise Residential Buildings. After a record-breaking decade of DOE: ASHRAE 90.1-2013 If DOE’s preliminary determination is economic losses due to natural disas- finalized, states would be required to ters, the United Nations has launched Saves 8.5% Source Energy review and certify that the provisions an initiative to improve corporations’ The U.S. Department of Energy of their commercial building codes re- disaster-risk-management strategies seeks to require states to adopt garding energy efficiency are updated and investment planning. the latest version of the key to meet or exceed Standard 90.1-2013. The R!SE initiative aims to help energy standard. Currently, states must meet or exceed corporations improve approaches to the 2010 standard, although some By Nick Dephtereos risk management and to create vol- states lag behind. untary industry standards that would Preliminary research by the U.S. In total, the DOE noted 52 positive influence and strengthen the demand Department of Energy (DOE) has impacts on energy efficiency from for risk-sensitive products. These shown that the ASHRAE 90.1-2013 90.1-2013 that it incorporated into the investments—ranging from property, energy efficiency standard would analysis. Many of these impacts, such tourist destinations, or agricultural achieve greater energy efficiency than as control requirements for lighting products—either are not highly prone

Environmental Building News • August 2014 p. 15 alterations and reduction of fan energy Air Conditioners Are With extreme heat projected to in- use, were the result of changes made Heating Up Our Cities crease this century, this positive feed- through a public review process. back loop could prove a public-health concern or put further strain on elec- For more information: Waste heat from air conditioners contributes to trical grids; in Phoenix, energy used higher nighttime temperatures, for cooling already sometimes rises U.S. Department of Energy in turn increasing cooling to half of the region’s total electrical energy.gov demands, according to a new consumption. study. The study’s authors note the potential $70 Million Fund Ready to By Candace Pearson for capturing waste heat for purpos- Finance Building Energy es such as heating water. That could It turns out when you left the door save Phoenix roughly 1,200 MWh of Projects open during the summer, you weren’t electricity per day as well as help mit- “cooling the whole neighborhood” igate the urban heat-island effect (see Capitalized with $70 million as your mother reprimanded; you Rural Areas Feel Heat from Cities) and and a quick application were probably heating it. New re- global warming. process, Eutectics is ready search from Arizona State University to finance small solar and suggests waste heat ejected from air By coupling a Weather Research and efficiency retrofits for conditioners is raising nighttime tem- Forecasting Model with data on build- commercial properties. peratures—at least in very hot and dry ings and energy use in the city, the cities—contributing to an even greater modeling used in the study, “Anthro- By Candace Pearson need for cooling. pogenic Heating of the Urban Envi- ronment due to Air Conditioning,” A new financing platform for small- In a computer simulation of 10 days accounted for both the size and shape and medium-sized energy-efficiency of extreme heat across the Phoenix of buildings as well as climatic factors and renewable-energy projects is now metropolitan area, researchers like wind speed. available from the Minneapolis-based found that the waste heat put out by company Eutectics. air-conditioning systems did not have Geared toward commercial projects a significant effect on air temperatures ranging from $25,000 to $5,000,000, the during the day when it was typically company plans to finance $70 million already above 106°F. However, during in projects across the nation in the first the night, when temperatures dropped round of funding. Eutectics prom- to around 80°F, heat expelled from the ises simple applications with quick indoors warmed the city air almost 2°F turnarounds. Projects applying for less in some locations. than $150,000 submit a one-page credit application and receive a response within 24 hours. To receive a quote, contractors submit the same informa- tion that they would on a typical bid sheet.

The platform may serve the needs of smaller projects and cash-flow-depen- dent businesses that other financing mechanisms have trouble reaching, according to Eutectics executive direc- tor Jeremy Kalin (see PACE Financing for Energy Improvements). A separate program, Eutectics’ Home SolarNote is targeted toward homeowners. For more information:

Eutectics Finance eutecticsfinance.com Photo: Todd Morris License: CC by 2.0 If waste heat from air conditioning units were used for beneficial purposes, Phoenix would save roughly 1,200 MWh per day, say researchers.

Environmental Building News • August 2014 p. 16 Emerging Technologies Twenty-Year Payback for from smaller mechanical systems, Address the Water-Energy Embodied Carbon of Triple- improved thermal comfort, and acous- tics to name a few. Furthermore, if Nexus Glazed Windows customers are seeking to reduce their carbon footprint, frame choice has DOE is highlighting It takes almost 20 years for a far larger impact, according to the technologies that triple-glazed windows to save researchers. Choosing wood over PVC simultaneously save water and enough energy to overcome saves 25 kgCO2e—10 years’ worth of energy, including supercritical their additional embodied operational savings—so over 20 years, carbon dioxide recompression carbon, according to a new a triple-pane, wood-framed window for power plants. study. will have a lower carbon footprint By Candace Pearson By Candace Pearson than a double-pane window with either a PVC or aluminum frame. Exploring the challenges and oppor- Triple-glazed windows may save more For more information: tunities of the water-energy nexus, a energy than double-paned windows, recent report from the U.S. Depart- but a recent study conducted by U.K.- ment of Energy (DOE) identifies sever- based consulting firm Inspired Effi- Circular Ecology al emerging technologies that will help ciency and footprinting expert Circu- circularecology.com/news/ conserve both resources. lar Ecology finds that in terms of their life-cycle carbon footprint, they don’t Some of the most promising tech- necessarily come out ahead. PRODUCT NEWS & REVIEWS nologies target thermoelectric power plants, which not only are the largest Researchers determined that the New Ground-Source Heat single source of water withdrawals in embodied carbon of an average Pumps Saving Energy and the U.S. but also convert less than half triple-glazed window is 51 kgCO2e of their primary energy to electricity, greater than a double-glazed window Dollars in Commercial according to the report (see Saving with the same frame type because Applications Water by Conserving Energy). One of the carbon dioxide emissions that solution is the use of supercritical car- are released from extraction, refine- WaterFurnace’s CLW Chiller

bon dioxide (SCO2) recompression in a ment, transport, and processing of the “geothermal” heat pump also closed-loop Brayton cycle (RCBC). additional layer of glass and pocket uses excess heat and cooling of gas between the panes. It would within a building to provide Because carbon dioxide is denser take almost 20 years for a triple-glazed energy-efficient HVAC. than water and has a higher thermal window to pay back this additional storage capacity, this process uses less embodied carbon—longer than the By Brent Ehrlich energy during recompression and re- lifetime of many windows. covers more waste heat, both of which Ground-source heat pumps (GSHP) also reduce cooling requirements. That doesn’t mean you shouldn’t use the consistent temperatures within According to the report, this technol- specify triple-pane glazings; there are the Earth as a heat sink to help pro- ogy could improve total plant effi- other benefits, including operational vide energy-efficient heating in the ciency 3%-4% and could be applied to cost savings, construction cost savings winter and cooling in the summer. existing coal plants, nuclear reactors, and concentrating solar power towers. The materials needed to handle the Comparing Carbon Footprint of Frame Materials requisite pressures and high power densities are expensive, but DOE re- cently produced a working prototype, and researchers have reported positive results at pilot scales.

Other emerging technologies covered by the report include advances in cooling systems, alternatives to fresh water for oil and gas production, de- salination techniques, and methods for recovering energy and nutrients from wastewater. Credit: Craig Jones, Circular Ecology Over the lifetime of a window, frame material makes more of a difference for carbon footprint than the number of panes, according to researchers.

Environmental Building News • August 2014 p. 17 Though GSHPs have fallen out Adding in a the ground of favor with some in the resi- loop dential green building industry who prefer less complicated air- The CLW Chiller uses only source heat pumps, GSHPs are water in the ground loop holding their own in commer- and can be installed using a cial applications. And products number of configurations, such as WaterFurnace’s CLW but Niles says that the Chiller can maximize HVAC company typically offers efficiency by taking advantage closed systems (where the of different water temperatures water is circulated through within a building’s zones while an HDPE loop) using deep still incorporating energy ex- vertical bore holes. The change with the ground. holes typically start at Moving heat around a 400 feet deep but can go to depths of 1,500 feet or building more, with deeper holes preferred since they require Most commercial heat pumps Photo: WaterFurnace International, Inc. less space, offer additional sold today are used in wa- The modular WaterFurnace CLW Chiller heat pump can produce hot thermal capacity, and usu- ter-loop heat pump systems and cold water simultaneously from its scroll compressors. It has piping ally cost less than drilling that move heat around large for hot and cold water as well as a ground loop to maximize heating and additional shallower holes. buildings and balance heating cooling efficiency, and individual units can be hooked together to serve a wide variety of building applications. and cooling demands. “In a Hybridizing for commercial building in the optimized savings shoulder months of fall and the unit while sending heat from that spring, the side of the building with process to the other side, allowing Despite the efficiency of a water-loop the sun facing it needs cooling, but the for simultaneous heating and cooling heat-pump system, the size of the other side might need heating,” said from only one unit. bore-hole field remains an issue. Alan Niles, WaterFurnace’s Western According to David Callan, P.E., vice regional commercial sales manager. The CLW uses a series of president of McGuire Engineers, The same effect can take place be- energy-efficient quad scroll compres- whose firm engineers both ground- tween the interior and the perimeter of sors and is designed with six pipes: source and conventional HVAC the building. one pair for chilled water, one pair for systems, a 500-foot-deep bore hole hot water, and the third for the ground might supply only two tons of cooling, Individual water-source heat pumps loop (a four-pipe, non-ground-source depending on climate, so a standard installed in each zone and hooked option is also available). The 60­­- to 1,000-ton GSHP system will take a lot into a loop can take advantage of that 140-ton units are modular and are of holes—potentially more than the dynamic to move the energy from typically hooked together to create a site can handle. one area to the other where needed. larger system, even replacing a central These water-loop systems can then chiller. “The reason we use a more Temperature swings can pose addi- be hooked into a ground loop, so if modular system, is we can bolt three tional challenges. “As you get to ex- the water in the loop gets too hot or or more together and better match the treme [cold] temperatures, you have to too cold, it can circulate through the simultaneous chilled- and hot-water add heat to the loop to get the system ground to be cooled or heated with- needs,” he said. “If you are no longer to work effectively,” said Callan. This out the use of fossil-fuel boilers or in balance and need cold water, then means adding a boiler. “On the flip additional chillers. (For more on how one of the modules switches over to a side, if you cannot reject enough heat this works, see Ground-Source Heat chiller and rejects heat in the ground in the summer, then you need to add a Pumps: Tapping the Earth’s Mass.) loop.” cooling tower.” So, depending on the application, the most extreme heat- WaterFurnace’s new CLW Chiller is At 36” wide and 76” tall, the modular ing and cooling conditions may add engineered to maximize the efficien- design of the CLW is small enough disproportionately to infrastructure cy of water-loop systems. Standard to be installed in retrofit applications. and maintenance costs, and the added GSHPs have individual units to Sophisticated software monitors and equipment could even reduce overall supply heating and cooling, so when controls the units to maintain tem- efficiency. heating and cooling are required at the peratures within the loop at peak effi- same time, two heat pumps have to be ciencies, and the units can be hooked But hybrid systems can also be very operating at the same time. The CLW into building automation systems and effective when used appropriately, can provide cooling from one side of monitored remotely. according to Niles. The Lincoln,

Environmental Building News • August 2014 p. 18 Nebraska, public schools use GSHPs there has been designed with a ground combining multiple products under but also have small boilers. Using the loop.” one set of details and one warranty. GSHPs lowers operating costs for the (Also see Tremco: Getting the Devil majority of the year, while the boiler In a climate like Las Vegas’s, energy ­ Out of Air and Water Details.) allows the facility to avoid using anti- may not end up being the biggest freeze in the system—an operational driver for adopting GSHPs. “When A family of products complication and an environmental you are using the ground instead of a concern—during the two or three cooling tower, you save a lot of water,” The Dow Corning Silicone Air Barrier weeks of extreme cold. says Niles. Before installing its GSHP, System, for commercial and multifam- “The Clark County School District was ily residential projects, combines the In Las Vegas, GSHPs have become evaporating 2 million gallons of water following: common in schools, but their systems each year just for one middle school,” are only partially dependent on the he claims. In a water-poor location • DefendAir 200 water-based ground loop. The GSHP carries the like Las Vegas, that amounts to a lot silicone liquid-applied air and majority of the load during the school of savings as well as a resource benefit water barrier. DefendAir adheres year, but a smaller fluid cooler han- for the region. to most substrates, including dles cooling in the summer, when masonry and gypsum or compos- the building is rarely occupied. This ite wood sheathing, and can be allows the GSHP to be sized smaller, Silicone Air Barrier applied with a sprayer or roller. It saving costs, while still taking advan- Offers Simple, Systematic is vapor-permeable, airtight, and tage of energy savings. UV-resistant. Approach Strong performance numbers— • The Silicone Transition System, or and other benefits A whole-building air barrier STS, includes silicone rubber strips system with a 15-year warranty and corners installed with silicone WaterFurnace does not have any is offered as a package from sealants instead of mechanical fas- real-world performance data on the Dow Corning. teners. The STS aids in providing CLW yet, but according to company airtight transitions from walls to By Tristan Roberts literature, the unit can attain cooling roofing membranes, curtainwalls, foundations, and other assemblies. EERs (energy efficiency ratios) greater As the continuity and durability of than 24 and COP (coefficient of perfor- air barriers get more attention from • The 758 and the 791 Silicone mance) greater than 5, depending on high-performance building projects Weatherproofing Sealants are two the size of the unit and other factors. (see The Hidden Science of High-Per- of a variety of compatible silicone But systems such as this one offer formance Building Assemblies), prod- sealants offered by Dow Corning as other potential advantages, as well; uct manufacturers are taking note. an adhesive for sheet- and flu- non-HVAC equipment such as walk- Dow Corning recently announced its id-applied weather barrier mate- in freezers can use the water loop for entry into a small but growing club: rials, and for use in through-wall cooling to improve their efficiency; companies offering whole-build- flashing and sealing penetrations, hotels and healthcare facilities can take ing air- and water-barrier systems respectively. advantage of domestic hot water creat- ed by the system; and the small size of the equipment and its quiet operation Foundation Detail can free up space in the building.

Overall costs of the CLW system are also difficult to estimate, but, in gen- eral, standard commercial GSHPs will always pay off within 20 years, claims Niles, so these systems are best suited to building owners with a long-term investment. With the added efficien- cies of the CLW system, that payback should be much shorter. Las Vegas did a feasibility study of standard GSHP systems 10 years ago for its schools, he said, and over a 20-year span their use resulted in an estimated savings of $1,000,000 compared to other systems.

“Ever since then, every school built Source: Dow Corning

Environmental Building News • August 2014 p. 19 According to Andrea Wagner, appli- of mechanical fasteners, and with the wet or dry to perform quality control cation engineer at Dow Corning, the DefendAir air barrier, he says, the in- but that the product tells its own story. sealants have been around for a couple stallers “feel that there is a tremendous She says it sags at 50 mils wet and is years or more, while the STS was savings in time.” see-through when it’s too thin. “It is introduced in 2012. The DefendAir air very easy to do, once the contractor barrier was the final piece, introduced According to Prchal, the five-gallon is aware of the thickness,” she says. about a year ago, and now with its containers of DefendAir that can be Wagner says that Dow Corning also unified system Dow Corning offers a applied with airless sprayers rather requires onsite adhesion testing as a 15-year air- and water-barrier war- than a heavier spray rig set it apart, quality control measure (other quality ranty, she says. According to Wagner, especially when it comes to re-seal- control measures are recommended the warranty is based on 5,000-hour ing penetrations in the air barrier but not required). accelerated aging testing, which made by various contractors, who can puts the materials through repeated easily re-seal the holes themselves. “It But Anis cautions, “Unlike the thicker temperature and water extremes, and avoids charge-backs; it avoids having fluid-applied systems, this one is in which she says led to no visual or per- specialty contractors coming back the thin category, which means that formance change in the material. multiple times repairing things,” he it’s more sensitive to good workman- says. Prchal claims that when contrac- ship.” Construction management is The system approach is “where the tors find out how easy the product is a key to success with any air barrier, market is headed and, in some parts of to apply, it even fosters cooperation. and “sometimes we’re limited in how the country, where it already is,” says “Everybody is much more open and much we can watch a contractor do Wagner. “Applying this as a system, up front in saying, ‘Hey, how do I get something,” says Anis. “I think it’s you know that the pieces all work this taken care of?’ versus contractors great to basically do away with the together, and they’ve been tested to- trying to hide things” or point a finger. compatibility issues that we encounter gether. They are put in a cavity that is with using differently sourced materi- hidden long-term,” she notes, “and we Quality control still key als, especially when we get into mod- don’t want to have to dig into a wall ified asphalts and window systems,” that’s failed because two pieces didn’t Is world peace around the corner? Anis says, calling the system “idiot play well together.” Wagdy Anis, FAIA, principal at Wiss, proof” from a design and specification Janney, Elstner Associates and an standpoint, but Dow Corning’s system Bob Prchal, building material divi- air barrier expert, says he is taking a hasn’t come up on a project for him sions manager at MGS Distributing, “wait-and-see attitude” until he has yet. which offers several air-barrier prod- more confidence in how the Dow ucts through locations in the Mid- Corning products are applied. Less material, less cost west, told EBN that the system had gained traction with contractors who DefendAir requires a dry thickness of Dow Corning’s thinner product seems are pleased with its “easy, systematic 15 mils, which means applying it at 30 to be key to its value proposition, process.” Prchal notes that the STS mils wet. Dow Corning’s Wagner says however. The thin, flexible coating strips are applied with sealants instead that a wet mil gauge can be used when means less material applied, and that translates to less cost, according to Parapet Cap Detail an industry source who preferred to remain anonymous because he rep- resents several companies.

Wagner quoted EBN a cost per square foot for the material, not including window transitions or labor, of $0.65- $0.80. According to Wagner, “The cost of the system is mid-stream for liquid-applied coatings. It is very cost-competitive with other systems.”

EBN’s source said that Dow Corning was less expensive than the other major product with a similar system and warranty, the ETA system from Tremco. He attributed the difference to Tremco having more steps and being applied more thickly, and to its extensive testing, which, while a likely Source: Dow Corning

Environmental Building News • August 2014 p. 20 benefit for performance, carries costs through to the product.

Other advantages cited by Wagner for Dow Corning’s silicone system are its flexibility and UV resistance. In an open-joint rainscreen system where light comes through, Wagner says De- fendAir and other components “won’t degrade over time.” It can accommo- date a variety of assembly types, in- cluding those with exterior insulation, and seals well around fasteners. Emissions certifications lacking

Dow Corning’s system is “100% silicone,” according to its marketing materials. That may make it sound innocuous, but silicone is a polymer and includes a few ingredients to Photo: Lamiot. License: CC-BY-SA 3.0. watch for. Wagner said that Dow This constructed wetland in Lanxmeer, a green district in the Netherlands, is an example of Corning wouldn’t disclose these, but low-impact development. the material safety data sheet (MSDS) for DefendAir lists formaldehyde (a BACKPAGE PRIMER known carcinogen) at 10 parts per to mimic natural hydrology, green infrastructure decreases runoff quan- million (ppm), acetaldehyde (a proba- Putting a “LID” on Harmful ble carcinogen) at 100 ppm, and ethyl tity and improves rainwater quality acrylate (a possible carcinogen) at 100 Stormwater Runoff by performing several interrelated ppm. It also contains 7%–13% titanium functions. dioxide, which is a possible carcino- Low-impact development Infiltration—Rather than sheeting gen when inhaled (which is not likely (LID) minimizes pavement off into streams or being drained to happen during a wet application, and maximizes rainwater into artificial detention ponds for which doesn’t involve ultrafine parti- infiltration, filtering out near-immediate release, rainwater cles—and Dow Corning’s application pollution and preventing enters porous soil—often specially en- guide doesn’t call for a respirator). erosion. gineered for the purpose—eventually By Paula Melton This formulation appears relatively contributing to groundwater recharge. Typically, the porous soil supports “clean,” especially in contrast with You may not think of parking lots and asphalt-based exterior-applied prod- plant growth, and the plants perform suburban lawns as sources of pollu- other functions; permeable pavement ucts, or silicone-based products with tion, but when it rains, they might as phthalate plasticizers, but MSDSes without plantings is an alternative well be Superfund sites: petrochem- way to encourage infiltration. are notoriously weak on chemical icals, heavy metals, and toxic levels data, and Wagner confirmed that Dow of nitrogen and phosphorous from Retention—A conventional retention Corning has not attained any major fertilizer can enter nearby waterways pond (a permanent artificial water emissions certifications for these prod- at high concentrations, harming local body that receives stormwater) or ucts (in contrast, Tremco has achieved ecosystems. During heavy storms, detention pond (a place where storm- Greenguard Gold certification for runoff from roofs, impervious pave- water is held for a few hours before all the components of its air-barrier ment, and compacted soil can also release, primarily to prevent flooding) system). cause erosion and flash floods and is not designed to treat rainwater or One can hope that Dow Corning will can sweep dangerous levels of silt—or replenish groundwater. In contrast, a up the ante on emissions to go along even human waste and concomitant LID landscape stores rainwater while with its bet on air-barrier systems, pathogens—into waterways. microbes in the soil filter out excess nutrients, heavy metals, and other but in the long run, its energy perfor- Green infrastructure and other strate- mance and ability to integrate into the pollutants. Eventually, the clean water gies related to low-impact development either trickles into groundwater or construction process will probably (LID) aim to prevent all these det- determine its success. evaporates or transpires safely (with- rimental effects of runoff, whether out ponding, which can provide a during a light rain or a heavy storm. breeding ground for mosquitoes). Integrated into landscape architecture

Environmental Building News • August 2014 p. 21 Evapotranspiration—Water evapo- ration from wet soil and transpiration from plants (release of water through leaves after it’s been drawn up through roots and used to aid photo- synthesis and other plant functions) return water to the atmosphere, continuing the water cycle. With the right plantings, transpiration may provide important “overflow” control; a series of heavy rainfalls can stress any management system, but research from Villanova University suggests that plants may compensate for satu- rated soil in a well-designed system by transpiring the excess water.

When designing for LID, project teams perform a hydrologic analysis, attempt- ing to calculate and then replicate pre-development hydrology—in- filtration, evapotranspiration, and groundwater discharge rates as well as runoff rate and volume—for the vast majority of rainfall events. Strategies for mimicking natural hydrology are site-specific and are ideally devel- oped through an integrative design process where soils and plantings play an integral role in building and site performance rather than a purely ornamental one.

Some of the strategies employed in LID include constructed wetlands, raingardens, bioswales, tree-planting boxes, permeable pavement, and green roofs. Rainwater harvesting is also considered a green-infrastructure strategy, though it does not mimic natural hydrology the way some of the other systems do.

In addition to preserving biodiver- sity and protecting public health, many LID strategies are less expen- sive to implement and maintain than conventional stormwater management infrastructure. For more information:

U.S. Environmental Protection Agency water.epa.gov

Environmental Building News • August 2014 p. 22