Our impressions from the 2015 Int'l Passivhaus Conference in Leipzig, Germany

A couple of weeks ago we went to Leipzig, Germany, to take part in the 19th International Passivhaus Conference, organized by the Passivhaus Institut in Darmstadt.

With approximately one thousand people attending from all over the world, this event marks the gathering of some of the AEC sector's greatest experts on energy efficiency.

The following are our impressions from the event...

2015 International Passivhaus Conference in Leipzig

The conference took place on Friday and Saturday, April 17-18, with the Thursday before dedicated to workshops and Sunday the 19th dedicated to guided tours of several passive buildings - houses, schools, pools, offices etc. - in the city of Leipzig and surrounding areas.

On our Facebook page, we published many photos of the events described here and of the innovative products on display at the expo to the side of the conference hall.

Workshop: Primary Energy Renewable (PER), PHPP9, DesignPH

Determining the PER factor (Primary Energy Renewable)

The day before the conference, Thursday the 16th, we took part in two separate workshops. The first, presented by Jessica Groove-Smith and Jan Steiger of the Passivhaus Institut, was dedicated to the new concept of Primary Energy Renewable (“PER”), included in version 9 of PHPP. The new "classes" of building certification by the Passivhaus Institut are going to be based on this PER value. The release of the English version of the PHPP has been announced for the incoming fall.

DesignPH - plugin di Sketchup per la progettazione di edifici passivi

During the same workshop, the presenters also illustrated DesignPH, a plug-in for SketchUp that allows you to model a passive building in 3D and to run a preliminary energy evaluation before exporting the data into PHPP. The importance of the new features of PHPP 9 and DesignPH are worth a dedicated article, which we are going to publish soon on our blog.

Workshop: ventilation

The second workshop, presented by Rainer Pfluger and Elisabeth Sibille, was dedicated to mechanical ventilation in buildings, a necessity if you want to guarantee comfort and indoor air quality both in new constructions and renovations. Regarding retrofits, the presenters illustrated a few case studies where the University of Innsbruck was called to optimize the design of these systems in order to improve performance and reduce costs.

An example of the distribution of air supply with the “active overflow” method.

The same system, called “active overflow”, has been successfully implemented in a few cases in California, in both residential and non residential buildings, with great success.

The conference

On Friday and Saturday, the actual conference itself was organized with four parallel sessions, with presentations in either English or German (and live translation via headphones). We'll now summarize here a few of the presentations we saw, and some of the information that stood out to us.

Alexandre Schuetze, who last year presented on data sensitivity in PHPP, illustrated his study on the shading factor for windows. He compared the values entered in PHPP with the results of a 3D simulation.

A comparison of shading values between PHPP and a 3D evaluation

The result of the analysis shows the current limits of the “static” values of PHPP. Since these values are so important for the assessment of potential overheating in summer, we can only hope that this issue is going to be addressed in the next versions of the PHPP. Rumors say that the upcoming version 2 of DesignPH (release scheduled for next autumn), may or may not include a 3D modeller for shading elements, something similar to EcoTect.

Matthias Laidig presented a three year monitoring of a building provided with a compact aggregate as the only heat/hot water generator.

An image of the presentation on the 3 years monitoring.

Even though the building itself was not strictly passive, the presentation was particularly interesting, with the analysis of actual yearly climate data, and the response given by the building and its services. The outcome was very positive, with the actual energy consumption being far lower than predicted.

Nick Grant illustrated the optimization of a passive school design, starting from an accurate analysis of the interior heat gains - in this case, the heat emitted by the children. This allowed the team to significantly cut costs, and at the same time to obtain a building that is more comfortable year round.

Nick Grant presenting improved passivhaus design for schools

Another piece of news introduced at the Conference was the new version of the PHVP, a software that allows for very quick, preliminary energy assessments for passive buildings. The tool is available online for free.

A screenshot of the new PHVP

Compared to the rather detailed PHPP, this tool requires a much more simplified input - so much so that its nickname is “5 minute PHPP”. The output is given both as energy demand and heat load, with an accuracy around 90-95% compared to the full PHPP calculation.

During the closing session of the Conference, Wolfgang Feist presented an honorary award to a few international pioneer projects from the 70s and 80s, that opened the way to the passive house movement.

Overall, our second experience with the International Conference was again a very positive one, both on a professional and personal level. The range of topics was very broad, ranging from local regulations to construction details, from user education to the latex technologies.

The conference aside, it was great to see some of the professionals we had met at last year's conference, as well as finally meet face to face with colleagues who until now have been our virtual friends via social media.

The next IPHC conference has been scheduled to take place in Darmstadt: a “homecoming” event in the city of the Passivhaus Institut to celebrate the 20th edition of the event.