WUFI® Passive V.3.2.0.1 validation using ANSI/ASHRAE Standard 140-2017

Good news: PHIUS has completed modeling to validate WUFI Passive according to ASHRAE 140. Read the full report here

ASHRAE 140 is a comprehensive Standard Method of Test (SMOT) for the evaluation of building energy analysis computer programs. The ASHRAE 140 report provides the information accrediting agencies or jurisdictions need for validation or acceptance of WUFI ® Passive for code and policy purposes. In short, the standard describes test buildings (cases) in significant detail in order to model the building and compare results versus other software. It contains a comprehensive description of test procedures, as well as predictions generated by WUFI Passive software evaluated against predictive benchmarks.

The table below provides a description of the test cases used for ASHRAE 140 Validation. 

Table 1

Annual Heating and Annual Cooling Load results were reported for most cases, except for L302-L324A which only analyzed heating. WUFI Passive results fell well into the suggested acceptance ranges in all test cases when following Class II Procedures of ASHRAE Standard 140.  Most results fell toward the center of the confidence range as shown in the graphs below.
AHL Results

ACL Results

Authors: Lisa White, Jasmine Garland

 

Transitioning from PHIUS+ to the PHIUS+ 2015 Passive Building Standard

Lisa White, PHIUS Certification Manager

 

Lisa White, PHIUS Certification Manager

Lisa White, PHIUS Certification Manager

Certification Update: PHIUS will not accept PHPP v9 for PHIUS+ 2015 Project Certification

Up until now, Passive House Institute US (PHIUS) has allowed project teams pursuing PHIUS+ Certification to use one of two passive house modeling tools to model their projects: 1) WUFI® Passive, the passive building modeling software developed by Fraunhofer IBP in collaboration with PHIUS and Owens Corning, and 2) Passive House Planning Package (PHPP), the passive house modeling tool developed by the Passivhaus Institut (PHI). However going forward PHIUS will not be accepting the latest version of PHPP v9 for PHIUS+ 2015 project certification.

Since the release of the PHIUS+ 2015 Passive Building Standard in March of 2015, PHIUS’ standard now differs significantly from the PHI standard. Specifically, the PHIUS+ 2015 Standard uses climate-specific targets for space conditioning energy use (the first such passive building standard to do so), limits overall energy use for residential buildings on a per person basis (rather than a square footage basis), and now uses a different metric for air infiltration.

For the first six months after the PHIUS+ 2015 Standard went live, project teams could elect to pursue either the earlier PHIUS+ Standard or the new PHIUS+ 2015 Standard. All new projects registered after September of 2015 are required to pursue certification under the PHIUS+ 2015 Standard.

 

Modeling Tools for Certification

Since the release of WUFI Passive in 2012, PHIUS has stopped teaching PHPP software during Certified Passive House Consultant (CPHC®) training and began exclusively teaching passive building energy modeling with WUFI Passive. PHIUS has since trained over 1,100 building professionals in the WUFI Passive software to date. In conjunction with the release of the PHIUS+ 2015 Standard, Fraunhofer released WUFI Passive v3.0, which includes a “PHIUS+ 2015 mode”. This software is uniquely suited to PHIUS+ 2015 projects, the North American passive building market, and is available for free on the Fraunhofer website.

Previously, project teams could use either WUFI Passive or PHPP for PHIUS+ project certification, and PHIUS continued to accept both modeling tools even after the release of the PHIUS+ 2015 standard. However, this was not without extra effort from the PHIUS project reviewers, as each PHPP submitted for PHIUS+ 2015 certification required a bit of “jury-rigging” in order to verify compliance with the PHIUS+ 2015 Standard. This adds time, and likely an extra layer of confusion, to the certification process.

In October 2015, the PHI released PHPP v9[1]. While this new software offers a variety of updates and new calculation protocols, PHIUS feels this software is no longer appropriate to verify compliance with the PHIUS+ 2015 Standard. As these two passive building standards diverge, the verification software also suitably continues to diverge. This ultimately does not come down to which software is “better”, but rather is simply about which software tool is most appropriate for each standard.

PHIUS will continue to accept earlier versions of PHPP for PHIUS+ 2015 certification, from the “06-02-10” IP overlay of the 2007 PHPP up through PHPPv8.5, but will not accept PHPP v9 for PHIUS+2015 certification. Eventually PHIUS will only be accepting WUFI Passive for modeling of PHIUS+ 2015 projects, but the date for this has not yet been determined.

For project teams with completed PHPPs that would like to transition over to WUFI WUFI logoPassive, PHIUS is offering a new service for a “one-time conversion” of your project from PHPP to WUFI Passive. The flat fee of $1000 for this service also includes the creation of a SketchUp file for the building and a walk-through of the completed model with PHIUS Certification staff. Contact certification@passivehouse.us for more information.

If you are a CPHC who has been meaning to venture into the world of WUFI Passive, PHIUS offers WUFI Passive training programs at various locations throughout the year to help get you up to speed on creating your own models in the software. Visit the WUFI Passive Training page for more information and to register for upcoming trainings.

Lastly, keep in mind that modeling tools are a small (albeit integral) part of the big picture. Try not to lose sight of the overall goal, which is to build energy efficient and resilient buildings that help to reduce the carbon footprint of the built environment. Regardless of your program preference, every step toward these goals is a step in the right direction.

 

[1] PHI allows project teams to pursue certification under previous iterations of their passive house standard as well as earlier versions of PHPP. However PHI’s new PER metric (the PE metric was used previously) requires using PHPP v9, the only version of the software able to calculate this. Thus PHPP v9 is not yet required for all projects; a sunset date for older versions of the standard and software has not yet been determined. For more information, see the “Criteria for the Passive House, EnerPHit and PHI Low Energy Building Standard” document on PHI’s website.

 

 

About WUFI Passive 

WUFI Passive is a powerful modeling program that dramatically improves the quality and efficiency of the passive building design process for Certified Passive House Consultants (CPHC®). The software allows for calculation of both static passive building energy modeling, as well as dynamic energy modeling for comfort and hygrothermal analysis. The user-friendly interface allows for SketchUp & Revit import, incorporates a seamless toggle between SI-IP, and generates high quality results reports for communication with clients and the PHIUS Certification team. Learn more at the WUFI website.

 

About the PHIUS+ 2015 Passive Building Standard 

Developed in cooperation with Building Science Corporation under a US Department of Energy grant, the PHIUS+ 2015 Passive Building Standard is the first and only passive building standard based upon climate-specific comfort and performance criteria aimed at presenting an affordable solution to achieving the most durable, resilient, energy-efficient building possible for a specific location. PHIUS+ 2015 is also the only passive building standard on the market that requires onsite QA/QC for certification.

Buildings designed and built to the PHIUS standard consume 86% less energy for heating and 46% less energy for cooling (depending on climate zone and building type) when compared to a code-compliant building (International Energy Conservation Code IECC 2009), resulting in an overall site Energy Use Intensity (EUI) of approximately 10-20 kBTU/ft2 year.

10th Annual NAPHC – best party of the year, maybe ever…

Wow – was that a successful conference! It has been a week and I am still processing it all. Chicago was unlike any other conference — things did not slow down in the office after it was all over, they rather accelerated. It indeed appears we have reached a tipping point.

From more than one person I heard that it seemed that the quality of work, detailing expertise and technical knowledge, size of projects and complexity of building types had reached a new high. And, compared to the early years, we were not just talking theory and intentions—but what people had done! Really impressive.

LEFT: Dr. Hartwig Künzel giving the Day 2 Keynote -- RIGHT: Sebastian Moreno-Vacca participating in the Architects' Hootenanny (L-R: T.McDonlad, T.Smith, J.Moskovitz, Sebastian, ?)

LEFT: Dr. Hartwig Künzel giving the Day 2 Keynote — RIGHT: Sebastian Moreno-Vacca participating in the Architects’ Hootenanny including (l-r): T.McDonald, T.Smith, J.Moskovitz, Sebastian, C.Hawbecker)

New modeling tools such as WUFI Passive (Technical keynote Hartwig Künzel, day two) are making building science interrelationships more visible and intuitively understandable. WUFI Passive is enabling CPHCs to optimize designs using “hygrothermal mass” (ever heard of that?) to optimize humidity loads and even to inform design decisions overall (as Sebastian Moreno-Vacca illustrated in his session) to create a unique architectural language! How cool is that! Science, heat fluxes and thermal dynamics begin to shape architectural form.

Dirk Lohan, Principal, Lohan Anderson -- Welcomes conference attendees to Chicago

Dirk Lohan, Principal, Lohan Anderson — Welcomes conference attendees to Chicago

Dirk Lohan—Mies Vander Rohe’s grandson, and an extremely accomplished architect in his own right—hinted at this development during his welcoming remarks.

“I believe that we will begin to see as beautiful what also is energy-conscious,” said Lohan.

Supported by the John D. and Catherine T. MacArthur Foundation

But maybe the most significant news is the explosive development in the multifamily affordable housing sector. It is seeing significant growth, interest and pilot developments going up in many places of the country. Thanks to the support from the John D. and Catherine T. MacArthur Foundation, we were able to make this our core topic for the conference and will be able to actively provide support to the affordable development community.

The pre-conference sessions included a daylong affordable housing Hootenanny that brought together successful affordable, multifamily housing project teams together who generously shared lessons learned and experience. Four different project teams presented during an intense full day. The morning and afternoon presentations drew full rooms of affordable housing developers who soaked up the information and had terrific, incisive questions

The same teams presented again during the core conference breakouts in a more condensed form for those who were unable to attend the hootenanny. In addition, there were more presentations on even bigger size affordable projects in progress:

  • A 101 unit affordable development in New York now under construction in the Rockaways (Steve Bluestone, Bluestone Org.)
  • A planned affordable retrofit of a 24 story historical brick building in Chicago (Doug Farr, Tony Holub from Farr and Assoc.), the Lawson House.
  • 24 story residence hall under construction in NYC (Matt Herman, BuroHappold)
L-R: Steve Bluestone presenting with Lisa White, Doug Farr, Matthew Herman

L-R: Steve Bluestone presenting with Lisa White, Doug Farr, Matthew Herman

Really amazing stuff.

Katherine Swenson

Katherine Swenson, Vice President, National Design Initiatives for Enterprise Community Partners — Day 1 Opening Keynote

Of course this growth has been fueled by forward-looking programs that recognize that energy efficient homes make so much sense for affordable housing developers/owners and dwellers. Katie Swenson from the Enterprise Foundation was a breath of fresh air–dynamic, positive, and motivating opening keynote. She explained that in her and her organization’s eyes energy is a critical part in assuring not just housing for people—but healthy housing! “Health is the new green,” she said, and of course passive housing delivers here with excellent comfort, indoor air quality and the added bonus of resiliency when the power goes out. Katie announced that the Green Communities criteria had just included PHIUS+ 2015 certification as one of the highest energy point options.

Other affordable housing agencies also have made a move: the Pennsylvania Housing Finance Agency (PHFA) awarded bonus points in its last round of selecting projects for Low Income Housing Tax Credits. More recently the New York State Homes & Community Renewal (HCR) effort was mentioned in a release regarding energy efficiency measures from the White House. Those agencies now directly encourage passive building standards in their RFPs. Remarkable!

Sam Rashkin, U.S. D.O.E. -- Closing Plenary Keynote

Sam Rashkin, U.S. D.O.E. — Closing Plenary Keynote

On the other coast. Seattle just amended their multifamily building code to allow additional floor area ration (FAR) for projects that meet the PHIUS+ 2015 criteria. That’s a significant incentive for developers.

Things are cookin’!

The core conference, as usual, was chock full of goodness. There were examples of how the new PHIUS+ 2015 climate specific passive building standards helped to optimize costs both here in North America (presentations by Chicago’s Tom Bassett-Dilley, Dan Whitmore, and) and internationally (Günther Gantolier from Italy). There were nuts-and-bolts presentations on wall assembly solutions (Tom Bassett-Dilley again), air and water barrier best practices (Marcus and Keith). And, the Builders Hootenanny—led by Hammer & Hand’s Sam Hagerman, focused on component challenges such as sourcing airtight FDA approved doors for commercial construction.

The U.S. DOE’s Sam Rashkin closed the conference with an unexpected message: he suggested that we needed to rename a few things to facilitate behavioral change. He posited that ZERH, LEED, PHIUS and other green building programs are essentially fossil fuel use rehab centers trying to rehabilitate an addicted nation and to show how it can be done differently. He received a standing ovation.

A few more comments on pre-conference workshops – three WUFI Passive classes drew almost 80 people and they all were super happy throughout the two days! Who would have thought! Happy people energy modeling!

LEFT: Marc Rosenbaum's lecture on Renewables -- RIGHT: Joe Lstiburek on Multifamily Building Science & HVAC

LEFT: Marc Rosenbaum’s lecture on Renewables — RIGHT: Joe Lstiburek on Multifamily Building Science & HVAC

Marc Rosenbaum single-handedly won first place in registering the most people for his class to connect passive principles with renewables to get to positive energy buildings (the logical next step).

Joe Lstiburek placed a close second (sorry Joe) and did a phenomenal job in covering ventilation concerns in large multifamily buildings. Rachel Wagner showed the most awesome cold climate details that I have ever seen. Galen Staengl took folks on a spin to design multifamily and commercial mechanical systems.

And Gary Klein topped it all off by reminding us that without efficient hot water systems design in multifamily, no cigar!

Thanks to all presenters and keynotes! You made this an excellent and memorable event.

I have not even mentioned the first North American Passive Building Project Awards—the entries were just beautiful projects—check out the winners here. I must mention the overall Best Project winner of 2015, as I believe this is pivotal: Orchards at Orenco. What a beautiful project, the largest fully certified PHIUS+ project in the country to date, a game-changer, underlining affordable multifamily projects on the rise.

I’m extremely happy that the Best Projects winners for young CPHC/architects was a tie, and both winners are women! Congrats to Barbara Gehrung and Tessa Smith! Go girls, you are the next generation of leaders!

L-R: Best Overall Project: Orchards at Orenco; Best Project by CPHC under 35 (tie): Island Passive House, Tessa Smith; Best Project by CPHC under 35 (tie): ECOMod South, Barbara Gehrung

L-R: Best Overall Project: Orchards at Orenco; Best Project by CPHC under 35 (tie): Island Passive House, Tessa Smith; Best Project by CPHC under 35 (tie): ECOMod South, Barbara Gehrung

One last note on a thing: Passive building people know how to party while devouring the most challenging, inspiring energy science, details, philosophies (Jevons paradox – Zack Semke’s fascinating lunch keynote) from the field.

And the architectural boat tour on Saturday to top it all off was almost surreal. When we were all out on Lake Michigan and the fireworks went off over the magnificent skyline, I thought, “that’s how we roll :).” Plus, the docent from the Chicago Architecture Foundation was a font of information, and even long-time Chicagoans learned a lot along the way. If you weren’t there, you missed the best passive building party of the year, maybe ever. (But we’ll try to top it, promise.)

Finally, for the crew that just can’t get enough, the Passive Projects Tour on Sunday was, as always, an enormous hit. Tom Bassett-Dilley and Brandon Weiss put together an array of completed and in-progress projects that generated a buzz at every stop. Thanks to Tom and Brandon and to PHA-Chicago for all your help!

Cheers!

Kat

 

Climate Data and PHIUS+ 2015

 

Adam2smAdam Cohen is a principal at Passiv Science in Roanoke, Va, a PHIUS CPHC®, a PHIUS Builder Training instructor, the builder/developer of multiple successful passive building projects, and a member of the PHIUS Technical Committee. With the release of the PHIUS+ 2015 climate-specific standard, Adam weighs in on the importance of climate data sets.

Project teams have always needed to be discerning about climate data sets they use in energy modeling.  Whether it’s WUFI Passive, Energy Plus, PHPP or any other software, the old adage garbage in = garbage out applies. Project teams always must analyze and make a call as to how accurate the climate file is.

For example, I worked on a Houston, Texas project a number of years ago and there were several climate datasets that were close and one that was very different. As a team, we had to decide how to approach this in the most logical and reasoned way.

Recently as I analyzed a Michigan project, I determined that my two dataset choices were “just not feeling exactly right” so I asked PHIUS’ Lisa White and Graham Wright to generate a custom set. I can’t know that this one is exactly right, but I know that it’s as accurate and “right” as we can make it.

Note that when multiple data sets are candidates, it is not just altitude that matters, but location of weather station (roof, ground, behind a shed, etc.). Ryan Abendroth blogged on the subject of selecting data sets (and when to consider having a custom dataset generated) and I recommend you give his post a read.

Since PHIUS+ 2015 is a climate specific standard, it’s all the more important to use the best available.  We all know that bad data is not exclusive to PHIUS (remember the Seattle weather debacle in early versions of the PHPP).

It’s incumbent on project teams to use science, reason and judgment in interpreting climate data sets. Being on the water, in the middle of a field or in the tarmac of an airport makes a difference.

In New York City, for example, we have an oddity: There are three dataset location choices.

A satellite photo of NYC with Central Park outlined. The climate date for the Park is substantially different than that for other parts of the city.

A satellite photo of NYC with Central Park outlined.

One is Central Park, and the PHIUS+ 2015 targets for that are substantially different than the others. But, counter to a Tweet calling into question the validity of the PHIUS+ NYC target numbers, they are different because the Central Park climate data is substantially different – probably due to vegetation countering the urban heat island effect. It has a dramatic and pretty fascinating effect on the microclimate, and the U.S. DOE has a nice read on the subject.

For project teams lucky enough to have access to multiple data sets for their location, by rational comparison, they should be able to make an intelligent decision to use a canned set or to have a custom set generated.

It also more important than ever that the PHIUS+ certifiers to examine the weather data provided by a project teams to see if the project team made a logical, rather then an easy selection of climate data.

In addition, we on the PHIUS Technical Committee will continue to collect and monitor data and will tweak certification protocols as we see the need. But, I remind all my fellow CPHCs that bad climate data sets are endemic in the industry and it is important that project teams make careful decisions and that they reach out to PHIUS staff to help when climate data sets just don’t seem right.

A message from Chris McTaggart, QA/QC Manager, PHIUS+ Program

New PHIUS+ QA/QC Manager Chris McTaggart

PHIUS has contracted with Chris McTaggart of Building Efficiency Resources to serve as our new QA/QC manager in support of the PHIUS+ Rater program.  For more information on this transition, please read a special message from Chris below.

Dear PHIUS+ Raters and constituents,

I am thrilled to have the opportunity to work with the Passive House Institute US as the QA/QC Manager in support of the PHIUS+ Rater program. My role will be primarily in working with PHIUS+ Raters to provide technical support and quality assurance review of documentation submissions for PHIUS+ Certified projects. Additionally, I will be supporting PHIUS as an organization by participating in the PHIUS Technical Committee and helping to refine and develop the passive house program certification standards.

I would like to thank the previous PHIUS+ QA/QC Manager, John Semmelhack, for his leadership in managing and developing the PHIUS+ Rater program. John is a first-rate professional, extremely knowledgeable building scientist, and an exceptionally personable and friendly person, and PHIUS has benefited tremendously from all the effort John was able to provide to the organization. I greatly appreciate John’s recommendation to PHIUS that I succeed him, and will do my best to pick up where John left off for all of our benefit.

A bit about my background… I am the co-principal and lead RESNET Quality Assurance Delegate (QAD) for Building Efficiency Resources (BER). BER is a national third-party RESNET QA Provider that works with over 150 independent raters and rating companies in 25 states. Throughout the past 6+ years, I have worked almost exclusively in providing technical support, training and mentorship to RESNET HERS Raters to help them understand program standards and how to execute their role in providing third-party verification. Additionally in this role, my company performs QA review of energy rating files both using site verification documentation as well as in the field.

In my role as QA/QC Manager for PHIUS, I hope to achieve the following:

  1. Provide thorough and timely technical support to PHIUS+ Raters and other program constituents regarding the role of third-party verification of PHIUS+ certification standards.
  2. Review all PHIUS+ project certification submissions by PHIUS+ Raters for accuracy in order to ensure that all program certification criteria is being properly verified.
  3. Help refine and improve the PHIUS+ program certification standards and affiliated documents so that PHIUS+ Raters clearly understand their role in performing verification services for PHIUS+ Certified projects, and so that role is as streamlined and efficient as possible.

As many of you know, the PHIUS+ certification standards are being evaluated and updated to help the program achieve greater levels of consistency and participation in the marketplace. A huge part of this process will be to properly codify the role and scope of third-party verification and quality assurance oversight of these standards so that consumers and program constituents are confident in the results of PHIUS+ certification.

My role in achieving success in this development process is clear: help make the on-site verification process for PHIUS+ certified projects as clear, organized and efficient as possible for all parties involved. This will ensure that PHIUS Certified Passive House Consultants (CPHCs), Raters, and affiliated project architects, engineers, owners, etc. will all be able to understand and communicate with one another about the program certification requirements. The end goal of this process is that PHIUS+ Certification and verification criteria is uniformly achieved and projects are successfully certified.

Achieving the above will require significant effort and feedback from PHIUS constituents regarding the current certification process so that future versions of the certification standards are as clear as possible. I encourage all of your participation and communication throughout this process, and encourage you to reach out to me with any questions, technical support issues or feedback that you may have.

I look forward to working with all of you.

Sincerely,

Chris McTaggart

cmctaggart@theber.com

800-399-9620×4