The North American Passive House Conference in San Francisco – a hard act to follow for NAPHC2015 (in Chicago)

Every year we say “This was the best passive house conference ever, we better stop now, we can’t possibly top this experience, the quality of the presenters, the “meat on the building science bones” presentations, technical details and specific construction solutions, cutting edge projects of all building types showcased throughout all climate zones, policy and government role discussions and incentives… and this year in addition to the Builders’ Hootenanny the Architects’ Hootenanny which, you might have guessed, was a hoot.

Let me take this opportunity to thank our community of longstanding CPHCs, PHIUS Certified Builders and PHIUS+ Raters who have shared this passive building path with us now for almost 10 years. It has been a pleasure knowing so many great folks with their hearts in the right place and a common characteristic: a determined pioneering spirit to make the energy transition in the way we build and live happen. Thanks to all passive building practitioners and to newcomers to the conference especially the international speakers from the UK and Japan.

Together you submitted nearly 100 abstracts and we had a hell of a time to choosing the best ones. We ended up with an unprecedented total of 72 sessions in 4 tracks this year, more than ever before (we cut the plenary short upon your request to get to the meaty sessions quicker and to have more of them).

Special thanks go to Sam Rashkin from the DOE, for his invaluable contributions to the tracks on government perspective and for the great partnership he and the DOE have provided to the PHIUS+ certification program over the past couple of years. Sam took time to be with us on the Sunday tour of passive buildings in the bay area, which was a lot of fun.

I would especially like to thank all of our outstanding pre-conference workshop presenters who covered topics in great depth, most popular were the Multifamily Palooza (kicked off by Chris Benedict who currently leads the field with the most passive projects in this sector realized), Passive Building Science with Joe Lstiburek (our unofficial lounge sponsor), packed the house closely followed by Mechanical Systems and commercial applications. Many thanks to the outstanding instructors who tackled more specific technical issues and new frontiers, such as efficient water systems design by Gary Klein, and Matthias Patzold from the Fraunhofer IBP and PHIUS staff presenting on dynamic energy modeling in WUFI Passive, THERM/windows modeling and PHIUS+ certification QAQC during the rater training. To all our presenters, pre-conference and main session: Thank you all so much! It would have not been possible without you!!!!

We owe many thanks to Michael Hindle, our charismatic Master of Ceremonies, and President of the Board of Managers of Passive House Alliance US (PHAUS). His opening speech was inspiring, artful and philosophical, The Passive House Alliance is now 16 chapters strong with 7 more in formation all over the country. It is starting to develop an impressive momentum regarding advocacy for passive buildings across the nation. Michael pledged to the membership that he would keep increasing member benefits and participation opportunities and closed with a call for action to join the many committees that have been formed to get the work done.

Michael also made a very well received announcement: the PHAUS  board has moved to remove any reference to a specific passive house standard from chapter founding documents. This decision rightly recognizes that since the inception of the passive house concept in the 70s in North America, it has undergone more than just one transformation and that evolution and learning will continue. It must continue to evolve for us to be successful. PHAUS leadership supports the new climate specific Passive Building standards brought forward by PHIUS as part of such evolution.

Bill Rose followed with the most thoughtful, most provocative keynote given at the North American Passive House Conference yet. Many of you came to me afterwards expressing that sentiment. He showed a short video recording from the early 70s of the researchers credited with formalizing the superinsulation/passive concepts. They worked at the Small Homes Council, University of Illinois at Urbana-Champaign in Illinois. The video reinforced the notion that the passive house community has a longstanding history here in the United States. He then showed a document written by the Nixon administration predicting peak oil and climate change to happen in 2010. It was a stunning piece of evidence that the issues had been known then, as well as the possible remedies outlined in the document. The document, then issued a clear call for action, recognizing the emerging passive community as having the best approach for reducing the demand side of buildings.

Rose made clear that facing the climate crisis means we also need to step up to transform the supply side of the system, coming up with strategies of how to keep the fossil fuel reserves in the ground and how to challenge the current economies that are all built around such assets. He ended provocatively saying, that we need to get to a point where we will be saying: “Energy (fossil fuels), what’s that?”

After the keynote and during all breaks, the exhibit hall was buzzing. A big thank you to all exhibitors of high performance materials and technologies! Every year the cast has been expanding significantly and new useful materials and systems manufacturers join the core group of providers. Thank you, without your products and services it would be impossible to realize passive buildings as well as we now do. Of course, also thank Exhibit Hall sponsor Bayer MaterialScience and our lanyard sponsor Hayward Lumber. Bill Hayward joined us on the tour and provides some great local background. Be sure to check the Hayward Health Home, a very cool initiative.

Achilles Karagiozis delivered the closing keynote. He spoke on the view forward, the implementation of passive buildings worldwide in all different climate zones and the challenges and responsibilities that come with it. He stressed the importance of dynamic modeling for accurate energy prediction results as passive building is applied in different climate zones. He cited an astounding example: WUFI Passive is now able to predict insulation material dependence on temperature on an hourly basis. And of course, this is important to assess hygrothermal performance of enclosures as well as to get the energy balances calculated with more accurate granularity. A great new age has arrived for us designers to manage our risks in designing passive buildings, thanks to the emergence of more powerful computing capabilities that make dynamic models feasible.

At closing, maybe best of all, the incredible sense of community of people who trust each other and know each other well:  We have been coming together now for almost a decade, reuniting at this amazing annual event working together to devise solutions for the North American market, its climate zones and building sector.

And this year, for the first time, the event was held in one of the largest and most exciting metropolitan areas: the San Francisco Bay area. This meant a significant step up from the previous conferences and importance in visibility of our community to city and government leaders, in California and beyond.  Passive building has turned the corner. And so has PHIUS as we were more than once told during the event by you.

PHIUS’ Senior Scientist Graham Wright’s presentation on new North American Passive Building Standards that are currently being completed under a DOE Building America grant was very well received: “This sounds like a really good program” was consistent feedback. The interest was so large that the session had to be moved from the break out room to the ball room. Most everybody was in support, not one negative comment! Kudos to excellent work by Graham Wright and a clearly laid out and scientifically founded argument by the tech committee.

And last but not least thanks to the PHAUS San Francisco chapter and John Sarter and Lizzie Adams from PHCA for helping to organize a fantastic tour of project on a beautiful Sunday in paradise: From multiuse building to state of the art office building to residential retrofit projects, it was great!

Thank you all for coming, for your contributions, participation and feedback on what to do better next year. Keep it coming so that the next act will be better yet again… see you in Chicago, details to come!

 

 

 

 

PHIUS Certified Data for Windows program online

Graham Wright, who heads up the PHIUS Certified Data for Windows program, joins us today to provide clarifications on some key features of the program. And to clear up some misinformation.

I get and see online a lot of questions about the PHIUS Certified Data for Windows program, and how it differs from PHI’s Euro-centric program. Apologies—it’s clear that we haven’t communicated the program as well as we should have—but we are catching up to ourselves.

I’m happy to report that we’ve got data and climate recommendations for a nice range of windows online here.

The table lists products, climate zone recommendations, full data certificates and supporting THERM files.

There are a lot more coming—and we’ll be converting this static table to an online database soon.

For manufacturers and suppliers, we invite you to download a detailed description of the certification process (with an application form), and the document is also available at the program overview page.

In the meantime, I hope to clear up misconceptions and concerns about the program:

I heard that the PHIUS Certified Data for Windows program doesn’t account for whole-window R-value. Is that correct?

In fact, the program does provide recommendations based on whole-window R-value, and all have the force of criteria as far as manufacturers are concerned. Also the program provides recommendations / criteria on solar heat gain coefficient.  (They vary by climate from about R-5 to R-9.)

Why doesn’t the program address surface temperature factor (“fRsi”)?

Eventually, it probably will – but on the list of important future program improvements for North America, it’s pretty far down the list, after data publication, NFRC harmonization, air-tightness-durability, and Canadian Energy Rating. That’s partly because fRsi isn’t pertinent to hot climates (and there’s a lot of hot climate zone in North America), and we decided to pay more attention to solar heat gain coefficient.

We cover the condensation / fRsi issue by providing the THERM files, which allow consultants to calculate it if they wish, and more precisely, with respect to the expected interior humidity conditions for their particular project and climate. (I made an ASHRAE 160 + ISO 13788 calculator for computing fRsi requirements climate- and project- specifically. We make it available during CPHC training, and if you email me at graham@passivehouse.us, I’ll be happy to send it to you.)

Moreover, both the fRsi criterion and the single-height bar on U-value (at about R-7) look to be legacies of the single-zone origin of PHI’s window program.

Setting that high bar at R-7 has certainly spurred innovation. But our multi-zone system does the same thing – people want to “level up” from zone 3 to 4 or from 4 to 5.  A single standard, when it comes to windows, fails to inform a shopper whether a window is appropriate for a passive house project because it’s overkill in some places and under kill in others.

It also hurts manufacturers—many of them mainstream producers of very affordable windows—who, right now, offer windows that will work well in mild climates. Designers, builders and clients should have those options.

Moreover, we find much to admire in the NFRC system and would like to get the best of both worlds. Funding for such harmonization work is being applied for.

Do we really need the PHIUS window program?

Absolutely.

PHIUS’ window program is moving toward a critical goal: producing data in the format that passive house consultants need, and that enables direct comparison to windows rated by other EN-based outfits like PHI or say, IFT Rosenheim. Both window industry representatives and passive designers have told us this is critical if we want to energize the market. To be sure, the programs’ fundamentals are aligned, but the presentation and recommendation level is different in a number of ways. For example, PHIUS’ program is more fussy about solar heat gain and zone granularity. PHI’s is more fussy about horizontal / vertical.

At PHIUS we believe that passive house principles apply universally, but a single criterion does not. From their Greenbuild presentation, it was clear to me that PHI recognizes the need for climate-specific recommendations for components, including windows.  But as I understand it their window certification is still pass/fail at one level. PHIUS has moved more quickly on this front. Going forward, if you hear “this is a passive house window” people should know to ask:  for what climate?  Be wary of claims about passive house windows that don’t show any numbers or label or certificate, it might just be loose talk.

Why such a long name? Why not just PHIUS Certified Window, for example

We settled on the name with care. The AAMA or NFRC would say, you don’t have a “window certification program” unless you address air / water / structural issues. So PHIUS is not certifying windows (and neither does PHI by such lights).

We’re certifying certain data about windows, namely thermal performance, modeled. Hence, “PHIUS Certified Data for Window Performance Program.”

We did not include the term “passive house” because while designed with passive house in mind, the data—even for windows that don’t receive recommendations for passive application—will be extremely useful for designers.

Join me at NESEA BE14 Passive Building Zone

March 4-6, 2014 at Boston’s Seaport World Trade Center

“A friend and co-instructor sneaks up on me and whispers into my ear – everybody should have the opportunity to live in a passive house – then he gives me this giant smile and I know he is dying to tell me something he is so excited about.”

For those who remember, that’s how I started my first blog on the NESEA trade show passive house products in 2012. “I have a dream of my very own passive house…”, was the title.

A year later this trend took off. The Passive House Institute US (PHIUS) and its membership organization the Passive House Alliance US (PHAUS) – the leading passive building research institute and alliance in the US – helped assemble a dedicated area for passive building vendors and organizations. In all, twelve highly impressive manufacturers of passive-appropriate components participated.

For 2014 NESEA took action and built on the success story and overwhelmingly positive responses of last year’s Passive Building place. The organizers blocked out an even greater area this year for this fast growing group of manufacturers.

So we are back! Bigger and better than ever! This time the Passive Building Place includes 21 exhibitors! I will again have the pleasure of guiding a tour on Wednesday, March 5th at 5.30 pm, visiting exhibitors with products and services indispensable to the passive building community. We will also visit some passive exhibitors who are located outside the zone. We’ll get a 3 minute elevator speech on each of the manufacturers’ products, a quick concise overview directly from those who know best. This year the professional film crew of Fine Homebuilding and Taunton Press will capture the tour to post on NESEA’s, the Passive House Alliance’s and Fine Home Building’s websites.

Passive building has traction—as the growth of certified projects above attests. And our roster of exhibitors at PHAUS’ Passive Place is also expanding. Thank you all for participating and putting your weight behind this exciting emerging construction market. Again, you are true leaders in this market transformation to achieve zero/positive energy buildings through passive design. Thanks again for joining:

475 High Performance Building Supply (Booth # 759)

Air Pohoda USA (Booth # 945)

H Window/Energate (Booth # 959)

Huber Engineered Woods (Booth # 953)

Klearwall Industries LLC (Booth # 751)

Intus Windows (Booth # 624)

Mitsubishi Electric (Booth # 707)

New England Fenestration (Booth # 955)

Passive House Institute US/Passive House Alliance (Booth # 753)

Passivhaus Maine/NA Passive House Network (Booth # 862)

Pinnacle Windows Solutions (Booth # 763)

PowerWise Systems (Booth # 856/854)

PROSOCO Inc. (Booth # 949)

Roxul (Booth # 860)

Solar Hot (Booth # 943)

Stiebel-Eltron Inc. (Booth # 749) 

The Energy Conservatory (Booth # 828) 

Transformations (Booth # 844) 

Yestermorrow Design/Build School (Booth # 1036) 

Zehnder America, Inc. (Booth # 864) 

Zola Windows (Booth # 755) 

There are other terrific vendors at BE14 – but time doesn’t permit us to visit all. Please, I encourage you to visit these vendors’ booths during your time on the show floor:

Affordable Comfort Inc. (Booth # 1024)

Bensonwood (Booth # 662)

Dryvit (Booth # 430)

Enovative (Booth # 939)

European Architectural Supply (Booth # 727)

Led Waves (Booth # 612)

Main Green Building Supply/ Northeast Performance Windows (Booth # 622)

National Fiber (Booth # 717)

Nectar Energy – Syracuse Tech Garden (Booth # 521)

New England Homes by Preferred Building Systems (Booth # 917)

Schock USA (Booth # 636)

ShowerStart (Booth # 723)

SIGA Cover, Inc. (Booth # 620)

Stebbins Duffy/Daikin (Booth # 418)

Steven Winter Associates (Booth # 450)

Tremco Barrier Solutions (Booth # 719)

Tremco Commercial Sealants and Waterproofing (Booth #907)

Vantem Panels (Booth # 652)

Viessmann Manufacturing (Booth # 666/565)

Yaro DSI (Booth # 660)

Let’s get to it…once again, organized by passive building design principles:

PRINCIPLE NO.1: CONTINUOUS INSULATION

Roxul is the coming superinsulation material, period. Not yet readily available in the US market, its benefits are attracting building professionals and Roxul is responding. Thank you Roxul!

So, why is this material such a great fit for highly insulated building envelopes? It is versatile. It can be used for roofing, cavity and curtain wall applications, it can be used for sound proofing in interior walls. Stone wool (or mineral wool as it is also called), maintains its R-value very well in extreme temperatures. That’s important for a designer, because the actual R-value of an insulation material varies with temperature. Foam insulation, for example, varies more and loses some of its R-value at very cold temperatures. Instead of the rated R6 it might only perform at an R4.

Also, in making stone wool, no blowing agents are required. The material maintains its physical properties over its lifetime and is dimensionally stable. Its advantages go on. It is non-combustible, “hydrophobic” (another word for water repellent), it can be used as a drain board and in contact with the ground. It provides no food for mold. It absorbs sound very well. And it is a very sustainable material. It comes as batts, higher density boards with higher R-values (depending on density R goes up) and I believe it can also be blown into cavities to make sure all little nooks and crannies are filled. What more do we want? The picture shows a mineral wool application in a superinsulated passive approved curtainwall application, thermally broken.

PRINCIPLES NO. 2+3: BUILD AIRTIGHT & PREVENT MOISTURE MIGRATION INTO WALL

PROSOCO, Inc. is a star among the air barrier systems manufacturers. It uses a liquid applied installation process that can easily be scaled from a small residential building to a 60 story apartment building. You can apply it to frame as well as to massive construction. Fluid exterior application assures evenness and continuity of the air barrier. Builders can dial in openness/permeability by specifying appropriate consistency of the material to meet climate specific hygrothermal requirements on wall assemblies. Prosoco made the news for meeting the Living Building Challenge: the company’s leading chemist figured out how to configure their product without Phthalates, which are considered highly carcinogenic. This achievement will likely result in an industry shift for the better. Kudos to the Prosoco team. The flagship project “the Bullitt Center” in Seattle used their product with amazing results: the blower door test showed a passive building level of air-tightness, under 0.6 ACH50.

Huber Engineered Woods, LLC offers the ZIP-system that many passive house teams have used as their air-tightness approach. In ZIP, the structural sheathing is used as the air-tight layer, and it’s 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 passive house consultant needs to pay very close attention to properly locate this air-tight/vapor control/zip system layer within the wall assembly. OSB has only a 0.7-1.0 perm rating.

475 High Performance Building Supply is a Brooklyn, NY based outfit focusing on a variety of European passive house air barrier product imports. They include smart airtightness membranes and tape solutions by INTELLO and Pro Clima and a wood fiber sheathing/insulation product from Gutex, that can also be used as an air tight layer. The company also distributes other European high performance products: triple pane skylights from Fakro, thermally broken fasteners from Schoeck and a through-wall decentralized apartment venting solution with a ceramic heat recovery core from Lunos. The system has a relatively low capacity to really provide sufficient balanced ventilation for new construction, but seems to be a great option for retrofit solutions. Point ventilation sources can be strategically placed after the fact in a living space without requiring space for mechanical installation or running ducts.

PRINCIPLE NO. 4: HIGH PERFORMANCE WINDOWS AND DOORS

The competition has increased and the prices have come down a bit: European windows are still stealing the show in regards to window performance and quality.

H Windows/Energate, Klearwall Industries, New England Fenestration and Zola European Windows are represented in the Passive Building Place for one stop shopping. Intus Windows is a Passive House Alliance US sponsor that is located across the aisle this year.All these windows are great options for the passive building envelope in a cold climate. The installation is quite different from the install of a typical North American window, so buyer and builder: inform yourself upfront to learn about these differences. The Passive Building Place will have installation examples where you can see how it’s done right and discuss the critical differences with the knowledgeable window experts.All European windows have tilt and turn hardware, typically open inward, are durable and very high quality, and use a thicker triple pane package that is in part responsible for the better thermal performance and a relatively high solar heat gain coefficient of around 0.5. The windows come in wood frame (thermally broken and insulated of course) as well as in clad or vinyl. I hear a few window companies will unveil new, even more improved high performance window models at NESEA. Come and see!

 

Pinnacle Window Solutions This company’s star is Alpen High Performance Products’ fiberglass window, the only North American made window on NESEA’s show floor that meets passive house requirements. This window has several advantages over its stellar European competitors. It is light compared to the European windows. The triple and quadruple pane is lighter because it uses a mylar film as its interior “pane(s)”. The frame itself is much skinnier which allows for more glass area and hence more solar gain if so desired. The fiberglass frame is also insulated and dimensionally more stable than vinyl, which at that slender level of frame is an important characteristic. And lastly, it comes with the customary mounting flange, no need to learn different installation protocols — high performance and business as usual.

 

Passive House Institute US | PHIUS is the leading passive building research organization in the United. It has made significant progress over the past year and a half establishing a window data certification program. The new program provides concise performance data verification for manufacturers who want to provide clients precise data for energy modeling, and an easier way to pick and chose windows for their respective climate zone. The right design decisions for various climates are not always obvious. The comprehensive window certificate provides guidance on what window combination of U-value and Solar Heat Gain Coefficient is the best for a particular climate. The comprehensive window certificate will be on display by the window manufacturers that have gone through the program. The data will also be made available on PHIUS’ website.

 

PRINCIPLE NO. 5: BALANCED VENTILATION WITH HEAT RECOVERY AND MINIMIZED SPACE CONDITIONING, EFFICIENT HOT WATER

 

Zehnder America, Inchas made an impressive run for the US market in terms of high performance balanced ventilation. Zehnder ventilators are all rated for efficiency on the European rating protocol, as well as by the Home Ventilation Institute. This is critical to the accuracy of energy modeling for passive buildings. Its two most popular models are Comfoair 350 and Novus 300. The efficiency ratings for heat recovery and efficiency of the input power required to move air are truly exceptional. Zehnder has all climate zones covered: it offers HRV and ERV counterflow heat exchange cores, an insulated box, options for defrost and pre-cooling / -heating / dehumidification through passive closed ground loop heat exchangers and summer bypasses. Zehnder offers a time saving polyethylene 3” ducting system that has become very popular for its ease of installation. More, the Comfo tubes are installed as home runs from the unit to the room, which provides built in sound proofing and makes telephone effects a non issue. (The finished installation does sometimes remind me of spaghetti). The ducts are double-walled, ribbed on the outside, smooth on the inside and provide some level of insulation as well.

 

Air Pohoda is a relative new kid on the block and comes in with a bang: not only does it offer a highly efficient balanced ventilation system with heat recovery; it also offers some new interesting features not seen in ERVs so far. Their model Ultima240E i-ERV is what they call the first smart ERV, able to control the level of humidity in a home. In the hot and/or humid climates of the United States, this could be a market changer. In such climates, it is not the sensible cooling load that drives the design of the mechanical system but the latent load! A good example of that condition is the first PHIUS+ certified home in Austin, Tex. Air Pohoda of course also has regular HRVs with respectable European style performances of heat exchange and fan energy consumption and is currently working on a smaller unit for smaller homes as well. Check ‘em out!

 

The Mitsubishi Electric mini-split heat pump is the perfect space conditioning point source companion solution to the ventilator. Mitsubishi has led the industry in efficiency ratings. Their mini-split systems are quickly becoming the most popular heating/cooling and dehumidification systems for Passive Homes in all of North America including the very cold climates. The units can be obtained 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! This year, Mitsubishi’s larger multi-zone heat pumps are also taking multifamily passive buildings by storm.

 

Stiebel-Eltron Inc. again provides an anchor point for the Passive Building Place. Solid engineering and world class energy efficiency characterize this company. Passive buildings allow designers to account for solar thermal energy in the energy balance. And PHIUS is looking at standard adaptation for the primary/source energy to more accurately reflect the US grid in the certification requirements (sorry, it will get harder to meet this requirement because the US grid is much dirtier than we have assumed in the previous editions of certification targets!!!). Consequently, solar thermal systems will become a very important component to meet the standard as well as super energy efficient and superior superinsulated hot water storage tanks to minimize heat losses of the overall system. And the same is true for Stiebel’s heat pump hot water heater, a true heat pump and not just a hybrid water heater, with an E.S. energy factor of 2.73. Impressive! The superior efficiency of the mechanical system is critical to meet the standards and to assure the lowest carbon emissions and source energy results that passive buildings are excelling in. In PHIUS+ certifications over the past year we have seen increased installations of heat pump hot water heaters inside of the thermal envelope. This confirms what we reported on last year: in super low load homes the heat pump hot water heater contributes to cooling and dehumidification, even in heating dominated climates and the location inside of the thermal envelope makes sense as long one does not only use direct electric heating. Last year the Stiebel team, seeing all the uptake in the passive building sector, was considering to bring some of their ventilation or even compact energy systems for very low load and passive homes that they produce for the European market to the US market. I am very curious to hear how that thought has progressed.

 

Solar Hot is providing efficient solar thermal systems and hot water tanks. As mentioned above, solar thermal technology is a good way to reduce the source energy in a passive home and it might become more important as we switch to the actual US primary energy conversion factor. We are glad that Solar Hot is joining the Passive Building Place this year, offering a choice to potential passive home clients.

 

 

PRINCIPLE NO. 6: ASSURE QUALITY AND MEASURE YOUR SUCCESS

 

Passive House Institute US | PHIUS  The PHIUS+ passive house and building certification program really excelled in 2013 and continued to grow exponentially (see fig. 1 above). We collaborated with the industry’s best quality assurance systems and requirements such as RESNET and adopted them to passive house and building practices. From the pre-certification process and design review/feedback through detailed quality assurance on site to the final issuance of the certificate and plaque – the process is comprehensive, complete, and diligent leaving little room for anything to go wrong. The result is a superior product we are proud of. A suite of certifications for professionals that hold up to accepted training practices and conventions (including industry appropriate passing rates for exams, continued education requirements, testing through the online testing platform Prometric etc.) assures that the design, construction and quality assurance team has been well educated on climate specific passive building design principles. There have been almost 1500 people who have gone through the trainings since 2008 in the US and Canada. CPHC© Passive House Consultants, certified PHIUS+ Raters and PHIUS Certified Builders work together seamlessly to meet the industry’s highest performance and quality standards. (Upcoming PHIUS trainings calendar.) Well done, PHIUS certification team! The certification has been recognized by the DOE encouraging Challenge Home builders to take the next step referring to the PHIUS+ certification on its website.

 

PowerWise Systems  PHIUS strongly recommends installing a monitoring system to confirm and maintain passive building performance. We’re partial to the inView Passive monitoring package from PowerWise as it is the only one that is customized to passive building principles and systems. PowerWise offers monitoring solutions for all building types, but the system especially developed for passive houses — a circuit-by-circuit energy management and monitoring system, sold us. It is the perfect partner system for the PHIUS+ passive house/building certification to assure quality.

 

Why would one want to add such a system? Despite a very rigorous commissioning and testing protocol during the construction process things can go wrong at a later time. Monitoring systems not only check if the predicted energy performance is being met (and help optimize the systems if there is a discrepancy), they can also be an important warning mechanism in the rare case that there is some malfunction. In very tight houses the indoor air quality can decline quickly if there is a failure in the ventilation system. The monitoring system provides feedback in such cases. Without such feedback the issue might go unnoticed for a long time (you can’t smell or see radon for example!).

 

Specially designed monitoring dashboards for all passive house typical systems components and indoor air aspects are part of the base package. Even a closed ground loop defrost system dashboard is included, which is a very passive-house-specific system. The passive house monitoring package is available as a baseline package as well as a custom package for monitoring needs above and beyond. Information on ordering the system and prices can be found on PHIUS’s website or on the PowerWise website.

 

The Energy Conservatory is a Passive House Alliance sponsor and long time high performance building trailblazer. This team is a terrific knowledge resource as well as equipment resource for all PHIUS+ Raters who are in the business of assuring quality. The Conservatory has never rested on its laurels and has forged ahead as the market for high performance homes kept changing. To their credit, they saw the passive building increase coming a mile away and developed testing equipment that is calibrated to measure the very low ventilation air flows that are characteristic for passive homes. The Mini-Fan Blower Door system development is another such example of market awareness: the duct blaster was repurposed and inserted into a red door, all one needs for a truly high performing very large home to conduct the blower door test!! Infrared cameras, flow blaster accessories, you can find it all at the Conservatory.

 

Transformations is one of the leading zero energy home consultants and builders in the Northeast. This firm is “zeroing in” so to speak on the sweet spot between passive and zero, which makes it a uniquely positioned company. Transformations just recently partnered with Bluestone RRSI, Building Science Corporation and PHIUS on a successful grant application to NYSERDA to rebuild Staten Island to Passive House Standards. We are all thrilled about this project and can’t wait to get started on it. As for Transformations: we will see more stunning and groundbreaking work from this company in the near future, I can almost guarantee it!

 

 

PRINCIPLE NO.7: SPREAD THE WORD, SHARE THE TALE AND TEACH ALL YOU HAVE LEARNED

 

The leading national advocacy, education and membership organization for passive building professionals in the US is the Passive House Alliance, a program of the Passive House Institute US. Passive House Alliance US | PHAUS co-organizes the annual North American Passive House Conference, now in its 9th year. It is the biggest educational event in North America in regards to technical information sharing by the community of passive building practitioners. The 2014 conference is scheduled for September 10-14 in San Francisco – San Mateo.

 

The Alliance also conducts ongoing webinars and offers opportunity for its members to share experiences, knowledge and information on new passive products, design challenges in different climates, and business and marketing issues. Membership also offers discounts for all training and conference events as well as for PHIUS+ certification. The alliance has grown significantly. There are today 14 chapters across the nation in all critical climate zones with three more in the works. PHAUS lists all educational events offered by PHIUS. All educational opportunities including the professional PHIUS Certificate trainings are listed in the Passive Building University. The schedule is complete through the end of June. More trainings will be announced for the second half of 2014 soon.

 

Passive House Institute US | PHIUS engaged in 2012 to developing a new modeling tool based on all our learning from projects across varied climate zones.The renowned Fraunhofer Institute for Building Physics, PHIUS and Owens Corning collaborated on a next generation passive building modeling tool – WUFI© Passive – which is now being taught by PHIUS as backbone tool of the CPHC training. The tool combines the monthly static energy balance with dynamic and hygrothermal capabilities. An eye opener for anyone who has tried to design a passive project in a North American climate zone using a simple energy balance calculator (and did not entirely believe the results). WUFI Passive will revolutionize our industry, once the word gets out. An introductory training for WUFI Passive is scheduled for Boston for April 24-25 at the Fraunhofer CSE in Boston.

 

Yestermorrow Design/Build School Yestermorrow has grown into the most successful educational partner of PHIUS. For the third year in a row, I arrived in Warren, Vt., this past December to find a full CPHC class. The demand for passive building classes prompted Yestermorrow to host the PHIUS Certified Builders class in April. (The class is sold out, but we’ve just scheduled another Builders program for Baltimore, May 10-13). Yestermorrow classes are unique. The CPHC class for example  is the only offering that provides all in person instruction (no online portion). It is absolutely intense: eight consecutive days conclude with the exam on the afternoon of the last day. People are on site 24/7, form study and discussion groups beyond the class time and prep for exam together. Yestermorrow provides an unforgettable learning experience with a retreat flavor.

 

Passivhaus Maine/NA Passive House Network is advocating for passive homes in the Upper North East. This non-profit organization conducts local seminars and educational events to spread the word about the benefits of passive homes and construction. It is a place where professionals who are already immersed in the field or those who are interested in getting involved can go to share or to get more information. This group is sharing the booth with the NA Passive House Network located in California, which is another advocacy and information sharing platform in the West.

 

I owe much gratitude to NESEA and NESEA staff who all have been terrific friends over the past few years. I like to say thank you for your support and trust. I admire that you constantly have your eye on the prize, pushing ahead, identifying the most important issues, and zeroing in on where we need to be in the future. It has made NESEA the leader in energy efficient construction and this team will maintain that leadership, shaping its conferences and educational offerings. My utmost respect. Thank you for allowing me to contribute to your event!

 

Notes from the Frankfurt Conference

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.

CompacFoam

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.

Progress!

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