Passive history (PHistory) Part II–study abroad and back home again

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.

The pace of passive building is accelerating, and providing us with a mother lode of monitored data.

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.

–Kat

 

 

 

 

 

 

Passive house history (PHistory) Part I–North American roots

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!

–Katrin

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.

Council Notes–the University of Illinois’ Small Homes Council periodical–featured the Low-Cal house back in 1981. Plans and energy modeling details were published in a standalone paper years earlier.

 

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.

An article about one of McCulley’s Lo-Cal houses appeared in the 1982 Louisville Courier-Journal. (Click to enlarge)

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.

SOUNDING FAMILIAR?

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.

REFINEMENT

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…

See the passive house history Part II

 

 

 

 

Part 3: NESEA BE13–the passive building journey continues…

 

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.

Onward!

Unofficial passive building principle No. 6:

ASSURE QUALITY AND MEASURE YOUR SUCCESS!

Only PHIUS+ projects earn the plaque!

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!

The most recent Yestermorrow CPHC class.

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!!!!!!

 

Part 2–NESEA BE 13: A guided tour of passive house trade show exhibitors

This is the second of a three-part series on passive building presence at NESEA BE13. Part one sets the stage for the series and part three completes the tour.  

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,

Katrin