The impetus for my journey to Frankfurt, Germany in April was the 17th International Passive House Conference. As I walked toward the venue it occurred to me that this is my 10th anniversary at that event…
…and that we’ve come a long way on this side of the pond. It looks like we might be able to match participation this year at our upcoming 8th Annual North American Passive House conference in Pittsburgh. Overall participation in Frankfurt, according to the distributed participants list, was 650 people.
Ninety exhibitors were on the exhibit floor. Among those were quite a few very large companies such as Saint-Gobain and Sto, who have embraced passive building solutions. One company struck me as especially interesting for the U.S. market: Compacfoam. They offer very simple thermally broken solutions using their compressed and structurally stable foam product. Those work for window installation, thermally broken point connections of curtain wall facades, point connections for balconies or porches attached back to the house structure as well as for the insulation of window frames. Those solutions could easily be implemented in the United States. All we need is the material.
Overall on the trade show floor, the innovations seemed to have leveled off some. In many cases the innovations presented were refinements of an already existing product. This is rather good news as it signals that passive in Europe has truly become mainstream. The smaller numbers of participants and exhibitors at the conference can be explained that way as well: other larger more general building conferences have absorbed the topic and are offering equally qualified information. Passive building is everywhere!
Some significant updates from the passive building modeling front: This year, only one year after the last 2012 PHPP update came out, a new 2013 PHPP version has been published. Word is that the PHI significantly improved the cooling demand and latent load algorithms to be more appropriate for hot and humid climates. A new latent demand annual budget had already been included in the overall cooling demand certification criterion for 2012.
Newly unveiled to the European market (it was released earlier here in the States) at the conference: WUFI Passive developed by Fraunhofer IBP. The new passive modeling tool — that in addition to just a static calculation method also includes hourly dynamic simulation capability and hygrothermal assessment — was presented to the worldwide passive building community. Overall it was good to see that everybody in the field is working diligently on passive modeling tools that are accurate for all climates including the more challenging hot and humid ones.
Back to the PHPP update: be aware that if you still use the older versions of PHPP (2007 through 2012) for your passive designs, it is very likely that your results may not be as accurate as they could be. You should consider upgrading. If you are working in more complex and challenging climates (very cold climate zones starting at 8 as well as mixed humid, hot humid, hot and dry climate zones, plus all zones with very high solar radiation) PHIUS very strongly recommends to use a dynamic model in addition to PHPP (or to use WUFI Passive which does both calculations — passive static verification and dynamic modeling).
Some caveats: The stated improvements/changes in the algorithms in PHPP 2013 are a great step – it marks an acknowledgement that cooling latent issues were indeed not properly addressed until now. But, these changes for cooling and latent have not yet been verified in the various North American climates. Moreover, with more built examples and data now available, the larger question is: How accurate can a limited static representation relying only on monthly climate data really be? It is very likely that it does not afford enough granularity to accurately predict very complex interactions of buildings with a multitude of climate factors.
For those more complex climates with heating, cooling, latent and solar climate factor combinations dynamic modeling appears to be quite a bit more accurate, allowing designers and consultants to limit the inherent risks in modeling: under or over-predicting performance as well as verifying that comfort conditions are assured throughout all rooms and spaces.
PHIUS is not alone with this recommendation of combining a dynamic model with a simplified static one for the best results. Belgium, the country that recently made the news with its decision to make Passive Standards code by 2015 for all new and retrofit construction projects, also requires all designers to back up the static passive house model with an additional dynamic model! Hence, the Belgian representatives of the Plate-forme Maison Passive I met with in Frankfurt were very interested and excited to learn about the advent of WUFI Passive.
In Part I of PHistory, we looked at the development of passive house’s foundation principles in North America, tracing back to work done in the 1970s and 1980s. The future for passive building was bright back then, but in the United States, conservation and energy issues were put on the back burner.
In the early 90s, physicist Wolfgang Feist picked up where the North Americans left off and continued research and development in Europe. He built on the work of Shurcliff and others to further codify the influence of highly improved envelope components on the minimization of the heat load in low energy buildings for his research project in Kranichstein, Germany. He then set out to make the case to the German scientific community and to the government that these principles could achieve much greater energy reductions than the low-energy homes (approx. 22 kBTU/sqft yr [70 kWh/sqm yr]) being promoted at the time.
Feist’s research facilitated many of the critical improvements predicted by Shurcliff: triple pane window with gas fillings, thermally broken spacers and frames, highly efficient heat exchangers, compact space conditioning systems and smart vapor retarders are among the most significant ones. Such improved passive house components soon became available on the European market at reasonable costs.
When Feist applied these principles and improved technologies in Germany in the 90s he also applied the very similar guiding energy metrics and boundary conditions defined earlier in the USA. He went on to apply the passive house boundary conditions to a swiss energy balancing model which resulted in the development of the PHPP – the first simplified static spreadsheet-based energy calculator and design tool for passive houses. He found that designing a building in the Central European climate to meet the 1W/sqft peak load resulted in an approximate annual heating demand of 15 kWh/sqm yr (4.75 kBTU/sqm yr), slightly lower than Shurcliff’s 15% limit for the annual heating demand in cold climates. That figure became the defining energy metric for the standard. The metric quickly became successful across Europe and is now considered by many to be the world’s leading standard in energy efficient construction today.
I became aware of the European flavor of passivhaus in 1993 while studying architecture at the Technische Universitaet of Berlin. I eventually landed in the United States to study for my Masters of architecture at Ball State. After some time in the United States—and taking heed of the growing science around climate change—I was motivated to test the principles here in the States. In 2002, I broke ground on the first home using the European metrics and design tools for passive houses, at that time still only available in the German language .
Smith House—completed in 2003 in Urbana, Ill.—has served its purpose well. It proved that the fundamental principles pioneered in the 1970s and 1980s in North America, and refined in Europe, worked. But not without some great effort and problem solving.
Since then it’s been gratifying to see the rekindled interest in passive building principles back here in North America. Our annual conference has grown from a few dozen committed visionaries to hundreds of building professionals and dozens of exhibitors. We have put passive building back on the map—now recognized by the U.S. DOE via its Challenge Home program and by RESNET via our PHIUS+ Certification program.
Thanks to the visionary—and courageous—pioneers of our day, projects have been completed in all U.S. climates (except the subtropical southern Florida region)
But we think we’re just at the beginning of an explosion in passive building.
The collective experience has shown that—as Shurcliff predicted—the general principles hold true in all climates, but also that the standard as formulated for Europe would benefit from refinement that takes into account the substantial climate zone variation in North America. For example, in very cold climates (Fairbanks, Alaska) home designs tend to require cost prohibitive overinsulation with walls of 3 feet thick, while in the warm regions of California comparatively very little insulation (between 3-5 inches) is required to meet the current standard–actually leaving further, cost-effective efficiency untapped.
This suggests it might be productive to adjust the standard–relaxing it somewhat in the North (as Shurcliff’s original limit already suggests) and tightening it in the South for North America.
For that reason, the PHIUS Technical Committee has begun work on refining the standard for North American climate zones. The committee is drawing on the now substantial body of data drawn from the growing number of finished projects and the growing body of monitored data we’ve accumulated over the past 10 years.
We think that with these tweaks, passive building—after a promising start and a disappointing lull, will fulfill its promise and become the mainstream design and performance market standard in North America.
In 2002, when I set out to build my own passive house as a proof of concept, I eventually selected a site in Urbana, Ill. I had was working in Chicago at the time, but Urbana made sense for several reasons: it offered affordable land, the city and its citizens have a progressive history in terms of environmental issues, and it is home to the University of Illinois at Urbana-Champaign (UIUC) and all the resources that a research institution offers.
What I’ve learned since then is that pioneering work at UIUC decades ago actually helped spawn what we now refer to as passive house. It’s a fascinating history, and one worth sharing here. To all the pioneers out there—weigh in with additions and clarifications. I hope you enjoy!
Passive house describes a set of design principles and defined boundary conditions that—if applied holistically—lead to a building that remains comfortable with only minimal active heating or cooling during extreme climate conditions. The specific boundary conditions determine the design of the thermal envelope. Minimized mechanical systems result from specific space conditioning energy consumption and peak loads: quantitative, measurable performance-based energy metrics for homes and buildings.
The underlying passive principles were pioneered and formulated in the United States and Canada in the 1970s and 80s following the oil embargo and resulting energy crisis of 1973. By 1986 the noted physicist William Shurcliff was able to summarize what at the time he considered a mature and widely adopted technology. He described the five main principles of superinsulation also known then as passive housing in his article int the 1986 Energy Review”:
a) thick insulation
b) airtight construction
c) prevention of moisture migration into cold regions within the walls, and other regions where much condensation could occur
d) optimum sizing of window areas
e) a steady supply of fresh air
He goes on to describe in detail the necessary components: triple pane windows, heat recovery ventilators, thermal bridge free and airtightness design strategies, vapor retarders, a small wood stove as a heat source for the entire house etc.
In essence, what Shurcliff termed “Superinsulation” was essentially identical to passive house as we know it today.
Where it started: Back to the future
Urbana, Illinois. The same Urbana that—by Kismet—is today home of PHIUS. In the early 1970s, a group of engineers and architects at the University of Illinois Small Homes Council (now knows as the Building Research Council) began experimenting with highly insulated envelope components. The group included included Wayne Schick (who coined the term superinsulation), W.S. Harris, R.A. Jones and S. Konzo. Their research culminated in the concept of the Lo-Cal (for low-calorie) house in 1976. (You can still buy original publications about Lo-Cal by the Council and Schick here. And Building Science Corporation’s Joe Lstiburek writes about it here.) Lo-Cal was projected to save 60% in energy consumption compared the most efficient design promoted at the time by the Department of Energy.
A young architect working with the Council at the time, Mike McCulley, built four Lo-Cal houses in Urbana and Champaign. The Council monitored and evaluated them for performance, and these projects gained some attention from press outlets around the country.
This Illinois group’s ideas greatly influenced a Canadian group of engineers working on the Saskatchewan Energy Conservation House (well chronicled in 2009 by Martin Holladay in Green Building Advisor–”Forgotten Pioneers of Energy Efficiency). They succeeded in reducing losses and peak loads even further. The peak load of the Conservation House in this extremely cold climate was designed to be approximately 1.5 W/sqft, equivalent to the best peak loads we are seeing in today’s passive houses in similar climates.
…A NEW LABEL–PASSIVE–IS BORN
The concepts gained momentum in both countries, spawning prototypes and buzz at building conferences. The press and the public took notice. The term superinsulation was evolving as the most commonly used label for this set of principles in a growing North American high performance building community.
In 1980 William Shurcliff published one of the first books on the topic, called “Superinsulation and Double Envelope Houses.” Shurcliff, an accomplished physicist who took up the subject after his retirement from Harvard, went on to publish many books on the passive solar and superinsulation concepts in the late 1970s and early 1980s. In fact, Shurcliff appears to be the first to have labeled the new concepts “passive house” in his 1982 self-published book “The Saunders-Shrewsbury House” [Shurcliff, 1982]. It describes direct-gain and indirect gain passive houses. Later in a 1986 article he states that “a superinsulated house is really a special type of a direct-gain passive solar house.”
Because many architects and builders felt that superinsulation was too narrow a term, passive housing started to be commonly used interchangeably with “superinsulation.
Regardless of labels, Shurcliff states that by the mid/late 80s there were tens of thousands of homes built in the United States and Canada (as many as in Europe today!) to these design specifications. By 1982 a movement had formed. Thousands of building professionals were traveling to conferences taking training to learn the techniques. Construction of such homes was growing “explosively” as Shurcliff puts it in one of his early books in 1980 (Superinsulated Homes and Air-to-Air Heat Exchangers). The Canadian government offered free builders trainings. Widely read magazines sprung up, amongst them the still today well known and respected Energy Design Update.
Shurcliff defined a superinsulated house as follows: “…a) receives only a modest amount of solar energy […], and b) is so well-insulated and so airtight that, throughout most of the winter, it is kept warm solely by the modest amount of solar energy received through the windows and by intrinsic heat, that is, heat from miscellaneous sources within the house. Little auxiliary heat is needed: less that 15% as much as is required in typical houses of comparable size built before 1974.”
He further explained: “The 15% limit on auxiliary heat […] was chosen because a house that conforms to this limit can get through the winter fairly tolerably even if auxiliary heat is cut off entirely. Specifically, the house will never cool down to 32 F. […] In summary, the basic strategy of superinsulation is to make the house so well-insulated and airtight – so conserving of heat – that it is kept warm almost entirely by heat that is received informally and is free.” (2)
What’s striking is that the 15% maximum limit cited for the annual heating demand compared to standard construction at the time is very close to the energy metric that defines today’s passive house criteria: 4.75 kBTU/sqft yr!
To explain: Comparing current contemporary home energy consumption for heating to the energy consumption of a home built in 1970 one finds that the reduction in heating energy consumption from 1975 to 2006 is approximately 17% (see DOE graph). In 2005 a typical home in the state of NY consumed approximately [34.76 kBTU/sqft yr] according to the EIA for heating. Increasing this energy consumption by approximately 20% (MEC-IECC Graph) results in 41.71 kBTU/sqft yr for a home built in 1974 (before the MEC took effect). 15% of that total value equals 6.25 kWh/sqm yr, (19.7 kWh/sqm yr) an energy metric limit very close to the current Central European passive house metric of 4.75 kBTU/sqft yr which was codified in the late 80s to early 90s.
Note that most passive houses at the time were built in quite a bit colder climates of the US and Canada. The colder climate boundary conditions are likely reflected in this slightly higher annual heating demand limit (as a direct result of greater peaks). Peak load then as it is today was understood to be the determining factor. Another curious historic trace of those early superinsulation experiences describing very low load homes similar to the European secondary passive house standard peak load threshold of 10 W/sqm exists in the International Energy Conservation Code (IECC). The current International Energy Conservation Code (IECC) still recognizes extremely low load homes, defining them as homes with a peak load equal or smaller than 1 W/sqft (10 W/sqm) for heating in section 101.5.2 [International Code Council, 2012] effectively exempting them from having to have a conventional auxiliary heating system. The code assumes in this case that the intrinsic heat sources are equal to the tiny peak losses aka no need for additional heat. According to the Code Council the IECC is the successor of the first 1975 Model Energy Code (MEC), from which this definition was originally adopted!
Shurcliff goes on to describe the performance of such houses in winter:
“1. The typical annual heat requirement on the auxiliary heating system is so small that the annual cost is almost negligible compared to the main household expenses [...] 2. The occupants benefit from the absence of drafts, cold floors, and cold spots near windows. 3. Because the south windows are of modest size, little or no sunny-day overheating occurs. 4. Anxiety as to possible failure of the auxiliary heating system is minimal because the rate of cool-down is so low (a fraction of a degree per hour) that the house can easily ride through a 24-hour period with no auxiliary-heat-input. 5. Thanks to the use of an air-to-air heat exchanger, humidity tends to remain in the desirable 40-60% range and there is a steady inflow of fresh air (at, typically, 50-150 CFM, or about half a house volume of fresh air per hour). 6. Little outdoor noise penetrates the house.”
He also notes that the orientation of the house is not critical to the concept. He says that the house can have almost any orientation, unlike only passive solar-heated designs that had to be oriented within 25 degrees of south.
The technology matured and the market began to follow. Energy Design Update published an entire edition in 1987 as a consumer guide devoted solely to the many air-to–air heat exchangers. The Canadians appear to have taken the technology lead in the 1980s. Shurcliff credits Harold Orr’s construction type from the Division of Building Research of the Canadian National Research Council to be the most widespread type being built in North America.
In 1984 young J.W. Lstiburek and J.K Lischkoff publish a book called “A New Approach to Affordable Low Energy House Construction,” further advancing various aspects of passive housing and related sciences. The “Superinsulated Home Book” by Ned Nissen and Gautum Dutt published in 1985 is the most advanced construction and detailing book in the industry at the time. The book even presented a detailed chapter on the theory of energy balancing and sample calculations for low load homes, explaining how to balance losses and gains to arrive at a design with an extremely low balance point temperature.
In 1988 Shurcliff concluded in his book “Superinsulated Houses and Air-To-Air Heat Exchangers” [Shurcliff, 1988] that this type of energy efficient home construction is here to stay and that one might see some further improvements in window technologies, vapor retarders, more efficient heat exchangers and compact minimized mechanical systems, “…but that there is no need to wait for such refinements. Superinsulation is already a mature and well proven technology.”
That was 1988, and the future of superinsulation/passive housing in the United States was bright, but…
OK, the finale! In part one we looked at the growth of passive building and how it’s reflected in Passive Place at BE13.
In part two we embarked on the passive building tour of the BE13 trade show floor–mapped to the fundamental principles of passive building.
Today, we introduce some unofficial passive building principles and visit some terrific partners.
Unofficial passive building principle No. 6:
ASSURE QUALITY AND MEASURE YOUR SUCCESS!
PHIUS (www.passivehouse.us) offers certification programs for projects and products. PHIUS+ Certification for new and retrofit applications is the only voluntary certification program in North America that requires a thorough design as well as an onsite third party review process. PHIUS+ certification is the most rigorous on the market–and the best value. That’s because PHIUS has partnered with the Department of Energy and RESNET. That means industry-standard certification protocols for design and onsite verification. And it means one-stop certification shopping. Earning PHIUS+ Certification also nets a HERS rating, DOE Challenge Home Status, and EnergyStar status.
PHIUS+ has jumpstarted certifications. We expect to have fully certified approximately 100 passive building projects by the end of 2013 in North America (if apartments are counted, then the number is closer to 200) and yes, the growth is exponential!
At the 7th Annual North American Passive House Conference in Denver last September, PHIUS launched its Window Data Verification Program. In cooperation with NFRC PHIUS is identifying a North American window data verification protocol and climate appropriate guidelines and recommendations. Several leading window manufacturers have signed on and submitted various window frame and glazing combinations for calculation and verification, and listing in the coming PHIUS window data base.
PHIUS recently partnered with PowerWise Systems–Booth 961 (http://www.powerwisesystems.com/passive) to promote their newest product – the inView Passive™ monitoring package. PowerWise offers all kinds of monitoring solutions for all building types—but we’re really excited about the value that the inView Passive monitoring package brings to our community. For passive builders, the proof is in the pudding–monitored performance is where it’s at. inView Passive includes monitoring dashboards optimized for typical passive house components and systems. We think it’s a great tool for anyone certifying a project through the PHIUS+ Certification and Quality Assurance Program.
Besides verifying predicted performance, monitoring systems like inView Passive can serve as early alerts for routine maintenance. For example, energy consumption might rise because a filter in the ventilator has not been cleaned on schedule. Monitoring also provides safety. Say one of the two ventilator fans fail; this could depressurize the house. Without monitoring, it might take some time to notice that indoor air quality declined, back drafting on vented appliances or fireplaces might have occurred or radon levels might have climbed.
inView Passive includes dashboards for typical passive house systems and components and indoor air aspects. Even a closed ground loop defrost system dashboard is included. Information on ordering the system and prices can be found on PHIUS’s website or on the PowerWise website. PHIUS has negotiated a 5% discount for all PHIUS+ certification enrolled projects and the Promo Code is available through PHIUS when registering.
The Energy Conservatory–Booth 828 (http://www.energyconservatory.com/) is the PHIUS+ Certified Rater’s best friend. Commissioning equipment for low load and airtight superinsulated homes has become more sophisticated and is now affordable. What exactly has to be commissioned and tested? The most obvious—the air-tightness of the envelope needs to get tested during construction and then again upon project completion. For very tight homes the rater can now use the Mini-Fan Blower Door System, a duct blaster in a newly developed red door insert to test the entire building, A small fan is all it takes if the home is that tight! The mechanical ventilation system also has to be commissioned and flows have to be verified. Very small ventilation air flows need to be measured. The Energy Conservatory Flow Blaster Accessory measures air flows at diffusers down to very low levels such as 10 CFMs. And lastly FLIR infrared cameras are used to check insulation quality, thermal bridging and also interior surface temperatures. Indispensable tools throughout QAQC process to verify a building has been built as designed and performs.
Unofficial passive building principle No. 7:
SPREAD THE WORD, SHARE THE TALE AND TEACH ALL YOU HAVE LEARNED
The leading national passive building research, education and alliance organizations are the Passive House Institute US (PHIUS) (www.passivehouse.us) and the Passive House Alliance US (PHAUS) (www.phaus.org).
PHIUS was founded by myself and Mike Kernagis in 2003, initially as Ecological Construction Laboratory, a non-profit, promoting and building passive houses for low income home buyers. It changed its name later to Passive House Institute US when it went national. Since 2008 PHIUS has been offering the hugely successful CPHC®Passive House Consultant training nationwide (NEW in 2013: Virtual segment online saving cost and travel time), we have added Certified PHIUS+ Rater trainings and PHIUS Certified Builder trainings over the last few years. We have trained more than 800 architects, engineers, energy consultants and builders and have certified more 500 of them as CPHCs, PHIUS Certified Builders and PHIUS+ Raters in the US and Canada. These are the folks you want on your passive building team!
In 2013 the renowned Fraunhofer Institute for Building Physics, PHIUS and Owens Corning collaborated on a new next-generation passive building modeling tool – WUFI© Passive. WUFI Passive now replaces PHPP as the backbone tool of the CPHC training. Like PHPP, the tool includes a static passive house energy balancing capability. But it also offers dynamic whole building energy modeling and individual component hygrothermal analysis. And it covers another critical modeling variable: thermal mass, which is necessary for the cooling energy balance. In WUFI Passive all of these assessments use the same project data; no double entry of project data in multiple modeling tools is necessary. Risk and performance management all in one. This tool is seriously cool!
In 2009 PHIUS launched a membership/chapter program, the Passive House Alliance US (PHAUS). The mission: to support the community of professionals who had been trained, to educate the public, and drive the market by involving manufacturers and advocating for making passive building standards the norm in North America. Since Mark Miller took on the Executive Director role of this ambitious program in 2011, PHAUS has a thriving and growing membership program, now up to 350 members. PHAUS’ manufacturer sponsors program (amongst them founding sponsor CertainTeed and Rocky Mountain Institute) is growing, as is the chapter organization—now up to 13 nationwide Chapters with two pending.
PHIUS and PHAUS have significantly shaped the landscape of passive buildings in America over the past 10 years and will continue on our mission: the transformation of the marketplace to make passive buildings commonplace. We are a non-profit and if you like what we have done so far and would like to help, you can donate to PHIUS, become a PHAUS member, or certify and train with us.
Building Science Corporation (http://www.buildingscience.com/) has been a leader in high performance building consulting and education for decades. BSC Principal Joe Lstiburek was a pioneer way back in the 1970s; that’s why at his keynote address at last year’s 7th Annual North American Passive House Conference, he closed his presentation with: “You guys are family.” I was totally moved—and I wasn’t alone. It was inspiring. Joe started building superinsulated buildings in the late 70s when he was just 23 years old!!! The details matched what we consider to be good passive building practice today. He has been on the forefront all along – vapor retarders, thermally broken fasteners, insulated foundation systems, energy heel trusses and even earth tubes (which he is not a great fan of )(link to his article). He knows what the trenches look like.
Building on that energy from the conference, BSC and PHIUS resolved to work together in promoting passive buildings. A first step: We decided to cooperate on the Passive Building University which lives on the PHAUS website (link): BSC bookends PHIUS executive certification classes with a Building Science Fundamentals program, the ultimate preparation for the CPHC Passive House Consultant class. BSC also offers Advanced Hygrothermal Analysis, truly building a science master class. I encourage you to visit BSCs table as they have the best selection of cutting edge literature that applies to passive buildings. Be prepared to spend some money and schlep books home!
Yestermorrow Design/Build School (http://www.yestermorrow.org/) This past December I arrived in Warren, Vt.,for the second CPHC class offered through the Yestermorrow Design/Build school. Yet another full class, intense and dynamic.
How is Yestermorrow different? It teaches all modules in person on 8 consecutive days with the exam on the 9th. People are on site 24/7, they form study and discussion groups beyond the class time and prep for exam together. You talk bonding…the food is exceptional and the people who show up for this are some of the smartest and unique. Yestermorrow truly attracts exceptional individuals. The classes took the passive discussion to new heights and aside from that, Vermont is just stunningly beautiful – an unforgettable learning experience with a retreat flavor.
Passive House New England (http://www.passivehousenewengland.org/) is one of the first independent passive house groups in the country. Many of its members are some of the most experienced CPHCs in the country with one or more certified passive houses under their belts. This group is a great resource for anyone who is interested in building a passive house or building in the North East region. The group has a very active meet up group schedule and hosts a passive house symposium annually in the fall highlighting most recent projects of special interest. Great group: Get involved!
Passivhaus Maine (http://www.passivhausmaine.org/) is carrying flag in Maine in regards to passive house (don’t you love the lobster in the logo?). This is also an area that has very many experienced passive house consultants and builders solidly on their way. This group also is making strides by providing great information and by putting on symposia. Join the meet up group and help getting the word out!
Well, that’s about it–and that’s plenty!
Thanks to NESEA and all the friends out East that have given me the opportunity to do this review and I hope to see a few of you on the BE13 NESEA trade show floor!!!!!!
Last year’s NESEA passive trade show tour was a huge success for exhibitors and attendees. This year’s will be even bigger and better: Remember, you can join me for a tour of Passive Place–a concentration of passive component manufacturers organized by PHAUS on Wednesday, March 6. I’ll also be doing a stage presentation just before the tour. Here are the details:
Demonstration: Cool Passive House Gadgets
Wednesday, March 6, 4:30, Stage 2, off the 1100 aisle
Passive House Trade Show Tour with Katrin Klingenberg
Wednesday, March 6, 5:30 – 6:30 (leaves from the NESEA Lounge #507)
If you can’t be there, like last year I’m going to run through the highlights here on the blog. Because we have more exhibitors, this year I’ve organized it around foundation passive building principles. We’re off!
Passive building principle No. 1: SUPERINSULATE AND USE THERMAL-BRIDGE FREE DETAILS
Knauf Insulation — Booth 862 (http://www.knaufinsulation.us/) is a leader in fiberglass insulation. Knauf makes every imaginable form of fiberglass insulation, but with an ecological twist: Knauf’s ECOBatt Glasswool insulation features a new binder that is more environmentally responsible; it reduces harmful chemicals and the amount of embodied energy typically found in binders. Knauf also uses post-consumer recycled glass bottles. Knauf’s application forms include blown-in blanket systems—perfect for passive building because they provide slightly higher R-values per inch, and the blown in material fills all nooks and crannies. Knauf also makes higher density batts for acoustic insulation purposes or high temperature pipe insulation. A great range of products for passive building!
The tour moves on with a quick walk down memory lane: I was introduced to the Schoeck Isokorb during my very first year of architectural education (it was the year the wall came down, when I had just moved to Berlin, Germany). Schoeck is to this day the world leader in thermally broken structural fasteners, check them out: Schoeck USA — Booth 662 (http://www.schock-us.com/).
Other insulation manufacturers on the NESEA floor are National Fiber — Booth 717 (http://www.nationalfiber.com/) with its cellulose insulation product and Icynene — Booth 911 (http://www.icynene.com/) with a spray foam product.
Passive building principle No. 2+3:
BUILD AIRTIGHT and PREVENT MOISTURE MIGRATION INTO WALL
Air barrier systems are getting smarter and more efficient to apply. PROSOCO, Inc. – Booth 949 (http://www.prosoco.com/) and Tremco Commercial Waterproofing & Sealants — Booth 860 (http://www.tremcosealants.com/) both offer exciting fluid-applied air and water barrier systems; they range from impermeable to vapor open with matching through-the-wall flashings. Tremco also offers specialty window-install systems to tie windows airtightly into the wall opening, such as the pre-compressed air sealing tape specifically developed for passive building.
Back to barrier systems: the planning and implementation of air-tight layers is particularly intimidating for large buildings. I know at least one passive building architect who’s having some sleepless nights worrying whether the airtight barrier will be installed perfectly. The fluid-applied systems from Prosoco and Tremco can help designers and builders of large projects sleep better. They optimize work flow and ease to prevent defects during application. Both brick and frame with exterior gypsum board construction types have lots of joints and interconnected air gaps. Wrapping the entire building from the outside in an airtight fluid applied skin is a great strategy to get all those gap leaks. The chemistry of these skins means they can now be dialed in just right in terms of permeability, based on the climate. Very exciting as we are moving more into multifamily new and retrofit construction.
Huber Engineered Woods LLC — Booth 953 (http://www.huberwood.com/) offers the ZIP-system that many passive buildings have used as their air-tightness approach. In this system the structural sheathing serves as the air-tight layer—perfect for single-family framed homes. All seams are sealed with a special tape that adheres to the sheathing permanently. This is a great approach to “tunnel through the cost barrier”: A material that is already necessary—the structural OSB—can be cross purposed as the air-tight layer and vapor control layer! But careful: this approach is highly climate specific. The CPHC must properly locate this air-tight/vapor control /zip system layer within the wall assembly. OSB has only a 0.7-1.0 perm rating.
SIGA — Booth 620 (http://www.sigacover.com/us/) offers European smart membranes for wind- and air tightness applications, impermeable or diffusion-open, and tapes and gaskets of all varieties. There are tapes for every occasion and with any desired perm rating. Creased tapes allow for easy and perfect installation in the 90 degree corners at windows. Really well thought out systems that have been proven to last over time!
475 High Performance Building Supply — Booth 759 (http://www.foursevenfive.com/) is a Brooklyn, NY based firm offering a variety of European passive house product imports. From airtightness membranes and tape solutions by INTELLO plus and Pro Clima, a wood fiber sheathing/insulation product from Gutex, triple pane skylights from Fakro to thermally broken fasteners from Schoeck. There is also a through-wall decentralized apartment venting solution with a ceramic heat recovery core from Lunos.
Passive building principle No. 4:
HIGH PERFORMANCE WINDOWS AND DOORS
Selecting windows with the right climate-specific thermal and solar gain performance is critical. We’re happy to see more manufacturers and more varieties than ever. And European windows are still mostly stealing the show.
Passive Place will feature H Windows/Energate — Booth 959 (http://www.hwindow.com/products/), Klearwall Industries — Booth 963 (http://www.klearwall.com/) and New England Fenestration / Unilux Windows, LLC — Booth 955 (http://www.newenglandfenestration.com/NEF_products.html). Energate was represented in the US early on and made headlines when they won the DC Solardecathlon with the Darmstadt team in 2007 and then did it again in 2009. They are window technology leaders.
A newer entrant in the North American market is the Ireland-based Klearwall (http://www.klearwall.com/), made from UPVC and available in various performance specs. The Thermal break in the frame is provided by adding still air chambers; for higher performance models the profile is filled with insulating foam. UPVC is a more affordable option than the wood frame windows. Both manufacturers carry the European passive house certification for the central European cool moderate climate.
New England Fenestration / Unilux features Unilux windows and doors from Germany. The window products have an excellent reputation for quality, and offer a wide choice of frames and performance specs for different climates in North America. The door options are available in high performance insulated varieties and feature superior airtightness and triple seals. Another excellent performer represented by this company are energy efficient windows from Schueco.
Pinnacle Window Solutions — Booth 763 (http://www.pinnaclewindowsolutions.net/) offers Alpen High Performance Products’ fiberglass window, the only North American made window on NESEA’s show floor that meets passive house requirements. Alpen (http://www.alpenhpp.com/) is the same group that developed the well known heat mirror technology, which has worked successfully in many passive buildings across the nation. This fiberglass window features excellent U-values well suited for all climates, from very cold to hot. Another plus: typical mounting flange installation means contractors will know how to tie it into the water resistive barrier.
Using suspended plastic film (instead of an additional glass pane) to increase the R-value yields a window that features quadruple pane window performance while maintaining a manageable weight. This is powerful for the cold and very cold climates in North America where even triple pane windows are not measuring up. That said, the high R of the heat mirror glazing package comes at a price: the Solar Heat Gain coefficient goes down significantly the better the R and the visible transmittance is lowered as well. The good news is that the owners of this technology are working to create even better windows that meet the passive house community’s needs in North America.
Intus Windows — Booth 624 (http://www.intuswindows.com/) are a very cost effective European window solution manufactured in Lithuania. It offers the European quality high performance frames, glazing, airtightness, multi-lock hardware as well as cool-moderate climate verification through the European window certification. Intus Windows also distributes the Schueco Passive House curtain wall system (cool moderate climate verified).”
Zola European Windows — Booth 628 (http://www.zolawindows.com/), another European import, is distributed from Denver, Colo. I have to say that I am somewhat partial to the Zola aesthetic, a more slender wood frame with a thermal break made from wood fiber, hence a more environmentally friendly solution over foam. But Zola also carries the UPVC window frame varieties, which are more affordable, as well. Zola’s windows carry the European cool moderate window value certification for its products.
Yet other European passive house certified window distributors with excellent performance and further options on the NESEA show floor are Bieber Windows — Booth 727 (http://www.bieberusa.com/), European Architectural Supply — Booth 729 (http://www.eas-usa.com/Products.cfm) and Yaro – DSI — Booth 559 (http://www.yaro-dsi.com/), all definitely worth a visit and a chat or two with the knowledgeable sales reps.
Passive building principle No. 5:
BALANCED VENTILATION WITH HEAT RECOVERY AND MINIMIZED SPACE CONDITIONING, EFFICIENT HOT WATER
Two veteran passive house manufacturers of the central piece of equipment–the ventilation system—offer distinctly different products that represent very different choices. We’re eager for more North American manufacturers to enter the market, but so far Ultimate Air — Booth 856 (http://www.ultimateair.com/) and Zehnder America, Inc. — Booth 864 (http://www.zehnderamerica.com/) are the only two meeting the passive building challenge.
Ultimate Air brings its proven American built and affordable classic Energy Recovery Ventilator – the RecoupAerator. It is the only residential product that uses an enthalpy wheel and meets the passive house efficiency requirements. The MERV 12 filter is integrated (it is the heat exchange medium in the wheel) and the humidity transfer rate can be adjusted from 40% to 20% by choice of different heat exchange filter pies…a pretty cool option to have in humid and mixed climates.
Over the past few years Zehnder has added more models. It offers a choice of HRV or ERV counter flow heat exchange cores, which are very different from the enthalpy wheel. Zehnder ventilators are all European rated products and recently also obtained North American Home Ventilation Institute efficiency ratings for its two most popular models, Comfoair 350 and Novus 300.
European testing methods differ from the HVI testing protocol and the two measures can’t be directly compared. Where we have HVI test results for both manufacturers we can quote apples to apples comparisons: Zehnder’s Comfoair 350 is rated by HVI at 93% Apparent Sensible Effectiveness (ASE) and the UltimateAir RecoupAerator is rated at 95%. Both ratings are truly exceptional. Both manufacturers offer options for defrost and pre-cooling / -heating / dehumidification through passive closed ground loop heat exchangers. Zehnder offers a time saving home run polyethylene 3” ducting system as well.
The Mitsubishi Electric — Booth 707 (http://www.mitsubishipro.com/en/professional/products/heat-pump-systems) mini-split heat pump is the perfect companion space conditioning point source solution to the ventilator. Mitsubishi has led with the highest efficiency ratings and its stable includes nine products that meet Energy Star’s most efficient equipment designation for 2013. Their mini-split systems have become popular choices for heating/cooling and dehumidification systems of choice for passive homes across North America’s climate zones. The units are available in small sizes for single zone and multi zone systems. They have excellent SEER ratings. They are available in three capacities, 9k, 12k and 15k BTU/h, the Hyper-Heat model that works down to temperatures as low as -15 F is available in 9k, 12k and 18k. An excellent, efficient, cost effective way to heat and cool a passive house by point source!
Also worth to visit Daiken AC – Altherma — Booth 418 (http://www.daikinac.com/commercial/home.asp), another leader in heat pump technology.
Stiebel Eltron Inc. — Booth 749 is one of the anchors of this year’s passive house product exhibit. I met Frank Stiebel at NESEA in 2006. I am sure he will not remember but I remember the conversation clearly and the impression it left me with. At the time we were looking at his solar thermal system (www.stiebel-eltron-usa.com/sol27.html) and the superior superinsulated hot water storage tank (www.stiebel-eltron-usa.com/sbb.html). There was nothing like it at the time. We had also used the instantaneous hot water heaters of the Tempra series (www.stiebel-eltron-usa.com/tempra.html) with great success in our first affordable passive house projects in Urbana, Ill.
Last year I reported on the heat pump hot water heater Accelera (www.stiebel-eltron-usa.com/accelera.html), a true heat pump (not a hybrid water heater as are most other products in this category). It’s easily the most energy efficient of the class and worth the money. Heat pump hot water heaters should be located inside the thermal envelope in super low load homes because they can contribute to cooling and dehumidification in the shoulder and summer seasons (this location even makes sense in heating dominated climates). Stiebel Eltron has 30 years of experience with this technology. Most recently Stiebel-Eltron in Europe is also offering a small decentralized through the wall ventilation unit with a ceramic heat exchanger. Those units “pulsate”, they reverse supply and exhaust ventilation and as the direction of the air flow changes across the ceramic heat exchanger energy is transferred and recovered. They are very efficient and are an alternate solution to centralized balanced ventilation systems, applicable to single room occupancies or small hotel rooms. Stiebel Eltron is considering introducing this product in the US. I admit I am a fan; Stiebel-Eltron products are well engineered and offer top performance!
Whew! Last year it took two posts to cover all the passive building exhibitors on the tour — this year, it’ll be three! I’ll post the third and final installment on March 5.
Thanks for reading,
This is the first of a three-part series on passive building presence at NESEA BE13. Parts two and three comprise a virtual tour of passive building component manufacturers and PHIUS partner organizations on the BE13 trade show floor.
Last year at NESEA BE12 more passive building component manufacturers than ever exhibited at the trade show. So many, in fact, that NESEA invited me to lead a passive-building focused, guided tour of the show to help builders, designers, and manufacturers connect. You may remember I also penned a two-part blog that provided a virtual tour for those not able to join us at NESEA.
Well, the growth in the passive building sector is accelerating. At PHIUS we see it in the recent explosive growth in PHIUS+ project certifications since we introduced the PHIUS+ Certification and Quality Assurance Program. We’re looking at the proverbial “hockey stick” growth curve…
Even more passive product manufacturers are at NESEA BE13 this year. The show runs March 6-7 at Boston’s Seaport World Trade Center (with workshops March 5). It’s a big event, and to help the passive building community make the most of the NESEA exhibit space, I’m going to a couple special evenings–including, again leading a tour:
Demonstration: Cool Passive House Gadgets
Wednesday, March 6, 4:30, Stage 2, off the 1100 aisle
Passive House Trade Show Tour with Katrin Klingenberg
Wednesday, March 6, 5:30 – 6:30 (leaves from the NESEA Lounge #507)
Hope you can join me–but if not, PHIUS and PHAUS (Passive House Alliance US, our chapter/member organization) have organized Passive Place. It’s like a passive house manufacturer village, bringing together 16 total passive building exhibitors right in the middle of the NESEA show floor. That’s critical mass! We salute those exhibitors who are joining us—you’re transforming the built environment.
PHIUS and PHAUS will be at booth 965—be sure to stop by on your visit to Passive Place. (Look for aerial banners identifying the area.) And here are the exhibitors who will be our neighbors:
Affordable Comfort Inc. (Booth # 951)
Huber Engineered Woods (Booth # 953)
H Window/Energate (Booth # 959)
Klearwall Industries LLC (Booth # 963)
Knauf Insulation (Booth # 862)
New England Fenestration / Unilux Windows, LLC (Booth # 955)
Pinnacle Windows Solutions (Booth # 763)
PowerWise Systems (Booth # 961)
PROSOCO Inc. (Booth # 949)
Stiebel-Eltron Inc. (Booth # 749)
Tremco Commercial Waterproofing & Sealants (Booth # 860)
Ultimate Air, Inc. (Booth # 856)
Zehnder America, Inc. (Booth # 864)
475 High Performance Building Supply (Booth # 759)
Be sure to also visit our generous PHAUS sponsors and non-profit partners who will also be on the trade show floor:
Building Science Corporation (Booth # 466)
The Energy Conservatory (Booth # 828)
Intus Windows (Booth # 624)
SIGA Cover, Inc. (Booth # 620)
Zola European Windows (Booth # 628)
Yestermorrow Design/Build School (Booth # 1012)
Passive House New England (Booth # 1036)
Passivhaus Maine (Booth # 1038)
And of course many thanks to NESEA. NESEA has led the way by embracing passive building methodologies and products naturally. As it should, it is part of NESEA’s DNA.
Finally, a quick suggestion: Sign up for these Passive Building Workshops:
Tuesday, March 5
9:00 am to Noon
WUFI Passive Workshop, Katrin Klingenberg
Learn about the next-generation passive/hygrothermal modeling tool
2:00 pm to 5:00 pm
Commercial Passive House Design Principles, Adam Cohen
Learn how the principles of commercial passive building from residential projects from one of the most experienced passive house design/build professionals on the planet.
Hope you can make the workshops—and of course, to the trade show floor!
Even if you can’t, you can take this virtual look of this year’s trade show with my next blog posts.
Graham Wright — in addition to be a pre-certifier for the PHIUS+ program — has been capably leading the efforts of the PHIUS Technical Committee since 2011. The Committee has produced work on a variety of subjects, and until now, Graham has been too busy to introduce himself and his fellow members. Without further delay, here’s Graham:
Hello everyone. I’m writing today to tell you about the PHIUS Technical Committee, who it is and what it does. It’s a real privilege for me to serve on the committee and to collaborate with people who are so capable and committed to advancing passive building here in North America.
I’ve been meaning to write this article introducing the PHIUS technical committee for a long time. The original crew was recruited by PHIUS Director Katrin Klingenberg over the summer of 2011, and we had our first face-to-face meeting at the North American Passive House conference in Maryland that September. We agreed that we wanted to get useful technical information out to the passive house community on a regular basis, and set ourselves a goal of publishing an article each month. We got right to work and published our first article in November, and stayed on our monthly schedule for five months before tackling the spray foam conundrum, which took us three months to deal with. (The committee tends to vote for quality over quantity, while remaining mindful that the best is the enemy of the good.)
From the beginning I felt it was important to be transparent about who the committee is and how it works. We passed some basic motions establishing our modified consensus process at the September 2011 conference and got to work publishing articles for you, but decided we better hold off on the “meet the tech committee article” until we had a proper set of bylaws that addressed things like elections, officer terms of service and so on. We got that in place by the Denver conference in September 2012 (having published seven articles by then).
Therefore this introduction is a bit overdue – I could have written this article at any point since October 2012 and it is now February 2013, so the delay is entirely my fault. Sorry. I know this transparency stuff is important but the technical stuff is more fun.
You can read the Technical Committee bylaws here. A couple of highlights: We operate by a modified consensus process; that is, we go up to three ballots seeking consensus (notionally proposal, counterproposal, and compromise) and if there’s still no consensus, a motion can pass on a three-fourths vote. This procedure also applies to membership – any member can nominate a new member and if the motion carries they are in. Members can also be voted off by the same procedure. Since inception, three people have stepped down and two have joined.
As to what the Tech Committee does, the bylaws document also contains the purpose statement, which is as follows:
- Identifying and prioritizing North American Passive House research projects.
- Developing and updating standard North American protocols for Passive House.
- Producing white papers and protocols describing the results of research, and protocol conclusions.
- Developing product certification criteria and details for North American climate zones.
- Serving as a peer review board for North American Passive House Conference abstract submissions.
- Producing one “Tech Corner” Article per month (when able) for the PHIUS Newsletter.
- Working with Education Committee to integrate research findings and developed protocols to CPHC curriculum and exam development.
There’s a lot about protocol, which may generate feelings of boredom, tedium, or stiflement, but the reason to love it is that protocol is a tool for streamlining the process of executing a high-performing passive building. It aims to format things so they are more cut-and-dried wherever possible and you don’t have to guess what to do, re-invent the screw, or go off on so many research projects on your own.
One of PHIUS’ CPHC instructors, Vic Weber—a former fighter pilot, is a strong advocate for protocol. He’s always saying stuff like:
“It’s like in the Navy, they would give us a new weapon system and tell us to just go figure it out. We would, but it was stupid. The Navy’s tech committee (TOPGUN) would never leave the fleet hanging for long…. It was always important to publish a standard that we thought would work, knowing we could change it or refine it as things developed. Give ‘em something to hang their hat upon…
…I think we need to put out exactly what PHIUS recommends that folks monitor, along with some recommendations for systems that will economically achieve it.”
Roger that, Commander. So, feedback from the instructors is one source of items for our to-do list. Another source is the creativity of teams submitting projects for certification. In addition to my Tech Committee hat, I also wear a PHIUS staff hat as a PHIUS+ pre-certification reviewer. Fairly often still, we reviewers have to make a judgment call on issues like, “I’m going to connect the shin bone to the arm bone as well as the thigh bone, how do I enter that into PHPP,” or “how do I come up with an efficiency or a U-value for this thing/stuff.” Sometimes the certification team can get together and feel comfortable making a judgment call on whether some tactic is cheating or just clever design, but sometimes we decide: This should go to the Tech Committee.
One of the very important matters before the Committees is “Developing and updating standard North American protocols for Passive House” Yes, this is the climate-specific standard adaptation matter that Katrin has written about before on this blog.
We have heard and discussed a number of interesting ideas about adapting the passive house standard to North America – some from the committee members and some from other experts like Bruce Kruger and Marc Rosenbaum. If you have a strong interest in this issue, Tech Committee membership may be for you. There is however, a price: You’ll have to work. One of the requirements of membership is “A Member is required to significantly contribute to at least one of the Committee’s articles, or works, per year.”
Right now, we are a bit under strength at eleven members. To maintain the flow of technical information that our community needs, we are putting out a call for new members.
If you share our enthusiasm for advancing the art and science of passive building in North America, please send me a statement of interests and resumé / curriculum vitae. Email: email@example.com
If accepted, you’ll be joining a terrific group of experienced and accomplished passive building science and construction professionals. See for yourself here.
You’ll also have an opportunity to work on a wide range of topics and issues that are critical to the passive building community. And you’ll be on the cutting edge of knowledge. Topics include:
- Standard adaptation by climate zone
- Ground contact modeling
- Thermal bridge calcs
- Internal heat gains
- Subsoil heat exchangers
- Exhaust air appliances
- Accounting for thermal mass
- Summer cooling by window ventilation
- Domestic hot water
- On-site renewables
- HRV / ERV
- Heat pump seasonal performance
- Custom solar thermal systems
- Complex mechanical systems
- Process loads in commercial buildings
- Embodied energy and other impacts
- Community-scale certification
- Moisture performance
- Details gallery
I can say from experience that it’s a privilege—not to mention fun—to work with committed, accomplished folks on moving passive building forward. I hope you’ll consider joining us.
The PHIUS Certified Passive House Consultant (CPHC) training—launched in 2008—is the first and still only training program geared to North America’s unique climates, construction details and market conditions. Over the years we’ve made strides toward streamlining the process—for example, we’ve implemented computerized testing at the end of each session, offered the training at multiple locations across the United States, and offered more standalone test opportunities nationwide. As a result, PHIUS is far and away leading training provider in the United States and Canada. More than 850 professionals have takend the 9-day training; 450 have gone on to pass the exam and earn the CPHC credential.
Now it’s time to take another leap forward. During our recent constituent survey, you were good enough to spend your valuable time and give us your feedback and loads of great suggestions. Many of you said that you want to take the CPHC training but you simply couldn’t be away from work for 9 days; that traveling once for a five-day session was a limit. That the time and travel for two in-class sessions was just too much.
We heard you: To make the training more accessible, we are making a portion of the class available in live, virtual format:
- Phase I will now be available via eight three-hour virtual sessions presented in collaboration with GreenExpo365, a national leader in virtual sustainable building training. Lecture and homework sessions—which are well-suited for this format—will be delivered twice a week for four weeks. The sessions will be taught live by PHIUS trainers and will feature live interaction. They will be also be recorded and made available to registered students for review and exam prep. Instructors will also hold “office hours” outside of class time to field questions from participants.
- Phase II will still be delivered in-class over 5 days—students can choose the most convenient of several in-class locations in the US and Canada. (See schedule here.)
The new format cuts travel and accommodation requirements in half. It allows students to take Phase I from their home or office. And—it allows PHIUS to reduce course fees, which are being reduced by $300! (See the full description here).
We’re very excited to launch this new format in April (see the schedule here) and we think it will open opportunities for more and more professionals to become CPHCs.
Still, you might be wondering why we have not taken the entire training online.
A proficient CPHC must fully understand the core underlying passive house principles, and have ability to optimize a project’s
energy balance and performance, all within the context of a realistic budget. Years of in-class instruction have taught us that mastering tools like WUFI Passive or PHPP demands personal interaction. Classroom give-and-take between a student and experienced instructor is critical to understanding work flows, appropriate component choices according to climate, and making cost-effective design choices based on modeling results.
In person, group interaction also greatly enhances the mechanical systems design exercises. Perhaps most important: We’ve seen firsthand the kind of personal connections that develop among classmates and between students and instructors. It has fostered a spirit of sharing and exchange, and forged connections that are the foundation of the passive house community. It has made us strong.
The PHIUS CPHC curriculum is constantly evolving—and it’s better than ever. It reflects the ever-growing collective knowledge and practical experience of our trainers–the most active CPHC consultants, who have build the most certified projects nationwide. Students received a binder of passive house information as well as CDs of class content.
And the CPHC training now incorporates the new WUFI Passive modeling tool. It is truly the dawn of a new age for passive designers! In addition to integrating WUFI Passive into CPHC training, PHIUS is offering three-day, standalone WUFI Passive training. It’s a great opportunity for CPHCs to refresh and upgrade their modeling skills.
I just finished participating in the first ever WUFI Passive 3-day training at Parsons College in NYC. CPHCs from the Northeast, Southeast, the Midwest and California and even CPHCs from areas with extreme climates like Texas and Toronto made the trek—and the energy was fantastic! (We just added WUFI Passive trainings in Chicago and Portland, Ore.)
This is a modern production tool with a terrific user interface. On day one we created a 3-D visualization in Sketch-up, imported it into WUFI Passive, and assigned window properties to the model. On day two we built assemblies in WUFI P in the 3D detail visualizer and on day three we’re trying out the dynamic options of the model for hygrothermal and comfort assessments.
We’re very excited about this new tool and the new CPHC training format. We expect that our partnership with the DOE—PHIUS+ Certification now also earns DOE Challenge Home and Energy Star designation—will put passive house on the national stage. And the demand for CPHCs will grow faster than ever.
We hope to see you all in 2013 and hope you will find the new format as exciting as we do!
Ryan Abendroth–Certification Manager at PHIUS–is back at Klingenblog with a post on selecting climate datasets.
First, I’m happy to announce that PHIUS just made available for free download more than 1,000 updated climate datasets! The PHIUS+ Climate Data Sets have been generated using the DRY data method within the software Meteonorm. I’ll have more in this post and an upcoming PHIUS Tech Corner will also address the subject in depth.
CPHCs should use the guidelines below to determine which set will most accurately represent their current project’s location. Generally, for most projects, one of the existing downloadable datasets will be accurate and appropriate for use with WUFI Passive or the PHPP. In some cases, though, a project will require a more refined dataset customized to a very granular level in terms of location and conditions.
–To start, avoid using data for a location more than fifty linear miles from your project location.
It’s worth noting that even projects within this range may–in some cases–benefit from custom generated data. This is especially true if there are microclimate issues or impacts from geographical features including altitude changes between the project site and the weather station. (Site elevation is a modifier on the climate page in the PHPP that is often overlooked.)
–We recommend using a different/custom dataset if the difference in elevation between the project site and station location is greater than 300-400 feet.
The climate modifier in the PHPP adjusts the data by taking every 1000 feet of elevation change and adjusting it by 3.6 degrees Fahrenheit. We have seen very large discrepancies due to this adjustment because often times, the real world conditions for high elevation changes consist of microclimate situations that are difficult for the linear scaling of the modifier to accurately reflect. If there is not a station location within 300-400 feet of the project site, check for local data. The elevation modifier can also be used to adjust a data set to be in line with local data sources. This is helpful in cases where there may not be a Typical Meteorological Year (TMY3) station for more than 50 miles, or there may be microclimate effects that occur at a given project location that are not able to be accounted for in the base data set. By using the modifier, a dataset can be adjusted up or down to account for the difference in temperatures between the generated data set and local, measured values.
Why accurate data is critical
Having exact sets generated for data points nearest to the project is important because in passive buildings, we are reducing the energy loads so dramatically. Small changes (say 1 degree) in the average temperature throughout the year can have dramatic effects. For a 2000 sq. ft. treated floor area (TFA) building in San Francisco that was meeting passive house criteria, the difference was ~15% for the Annual Heat Demand. This is especially important when considering all of the factors mentioned above. For one project location, I gathered data directly from the station point and then generated a second set based on interpolation through Meteonorm to the exact same coordinates of the station. The result was a variance of +/- 4 degrees Fahrenheit as compared to the base non-interpolated values which equated to ~25%+ difference in Annual Heat Demand in that particular project.
Nothing changed about the location, just the method of generation that was utilized (straight derivation or interpolation). This is the basis behind my insistence on using TMY3 station points whenever possible.
News in the world of Climate File Generation:
The iPHA recently published a tool to generate climate data files for locations where none yet exist. It is an excellent attempt but the fine print recommends use for design only—not certification. This is because the granularity of the tool is only 75 miles by 75 miles, a resolution not small enough for most locations in the United States. It may be relatively accurate in the central plains, but once major geographical features come into play, the microclimate effects will make the iPHA tool only a rough estimate (which reflects the stipulation to use it as a design tool only) due to the spatial resolution being roughly 1 degree about the equator with some data being even less precise (referenced in page 321 of the 16th International Passive House Conference 2012 – Conference Proceedings).
Frequently asked questions:
Is the Climate Data robust enough?
Yes. The passive house verification in WUFI Passive and in PHPP allow architects/designers to design buildings based on two methods, either annual or monthly. The monthly method is the one you want to use for a variety of reasons (more on this later). Because of this, the climate data has been set up to not require very small increments or time steps in the calculation. The actual data sets are a representation of the hourly data from TMY3 sets. It has just been broken down into month-by-month averages instead of a large drawn out set with values every 15 minute or every hour.
What about more exact time steps or hourly values?
If greater specificity is needed in terms of time steps a different program should be used that has dynamic calculation capabilities instead of a standard static model. In many cases, this is not necessary as the passive house verification in WUFI Passive (and PHPP) has been set up to simulate dynamic modeling for passive house buildings. This is made possible because the short term fluctuations should matter less as the lag effect due to super insulation, air-tightness, and thermal mass, provides a buffer against isolated peak conditions.
This past May, the average monthly temperature was 73.2 degrees F, but the PHPP has the temperature as 64.2 degrees F?
Prolonged peak conditions have a large effect in terms of real world performance. However, there is a real difference between weather and climate. The climate is a an average of many years, while the weather is what occurs at any given time. Climate data is unable to predict any given trend in the future weather. Next year, the monthly average for may could be 55F and even out this year’s unseasonable warm spell.
What about climate change? Should we make data for the future?
This is inherently difficult to predict. While many places represent a trend that is most likely warming, there are others where opposite phenomena could occur. Also changing could be the amount of rain, and the corresponding changes in radiation associated with an increase or decrease in cloud cover. Therefore, we should use the data that is available for our area and worry about updating it when new data comes out, but not worry about trying to predict the future.
What about humidity?
Humidity can be determined through the dew point temperature and average temperature within the climate data set. As mentioned earlier, this is a monthly value and not as specific as may be needed for some modeling methods, but should be fine in most climates (more on this from future PHIUS Technical Committee articles).
Where can I see the most up to date list of available data sets?
They can be found here on the PHIUS website: http://www.passivehouse.us/passiveHouse/Climate_Data_Sets.html
All datasets listed are available for free download.
If I need a set generated, how does that happen?
First, check to see if the list of climate data sets has one that is suitable. If not, inquire with firstname.lastname@example.org to determine the suitability of a site or to have a custom data set generated.
What does a custom generated dataset cost?
PHAUS Members – $200
Non-Members – $250
Email email@example.com for more information about custom datasets.
Hello, it’s Ryan Abendroth here. I’m the Certification Manager at PHIUS. With the new year coming, it’s a good time to discuss the upcoming changes to the certification process and what it means for project teams pursuing PHIUS+ Certification.
Starting January 1, 2013, projects submitted for PHIUS+ Certification must meet the U.S. Department of Energy’s Challenge Home and the DOE/EPA Energy Star 3.0 requirements. This is a good thing—and will result in a streamlined, one-stop certification process, as I’ll explain later in the blog.
But, if you’re a CPHC with an ongoing project designed with the current certification requirements in mind, I encourage you to submit it for PHIUS+ Certification before the end of the year. Any project submitted before January 1 will be PHIUS+ Certified to current (2012) QA/QC requirements and will not need to also meet Challenge Home and Energy Star status. This will avoid any additional work on projects that were designed before the Challenge Home harmonization (this is especially important for projects that PHIUS first reviewed years ago, before PHIUS+ was established, but have been delayed).
For your project to be recognized as submitted you must supply a signed contract and PHIUS+ Certification payment. You’ll find the fee schedule here.
- You can request the contract directly from me or simply email firstname.lastname@example.org
- You can sign, scan and return the contract electronically or by snail mail to the PHIUS address: 110 S. Race, Suites 202, Urbana, IL 61801
- Payment can be made by check via mail or via PayPal on the PHIUS Web site
For projects with expected completion dates in the next several months, I strongly encourage you to submit your documentation for certification before the end of the year—they likely were designed well before the US DOE and PHIUS established the new partnership.
Moving forward, I firmly believe that the upcoming changes streamline and simplify the PHIUS+ Certification process. In most cases, design changes will not be necessary for passive houses to achieve all three certifications. Currently, the QA/QC process for PHIUS+ includes a spreadsheet to be filled out by the PHIUS+ Rater in addition to the required tests of ventilation commissioning and blower door. With the new Challenge Home requirements, the PHIUS+ Spreadsheet will shrink in scope and complexity. The Energy Star 3.0 and Challenge Home checklists will take the place of some of the provisions currently in the PHIUS+ spreadsheet. You can download the new PHIUS+ spreadsheet here.
As mentioned above, starting January 1, 2013, all projects pursuing PHIUS+ Certification will be required to meet the specification for Energy Star and the US Department of Energy’s Challenge Home Certifications. Through the partnership between Challenge Home and PHIUS, there have been some exemptions granted within the Challenge Home and Energy Star requirements for projects pursuing PHIUS+ Certification. More news on these exemptions will be provided as soon as the updated Challenge Home documents are released.
Feel free to ask any questions here via comments here on the blog or by email at email@example.com