Germany’s Passive House Standard Gains Momentum?

One of the original Passive Houses at Darmstadt, Germany

Dresden/Darmstadt, GERMANY–Over a thousand people attended the 14^th International Passive House Conference held recently in Dresden, Germany. The Passive House (Passivhaus in German), a construction standard that was conceived in Germany, proves that it is possible to build or refurbish buildings in a sustainable, comfortable and affordable way. It results in ultra-low energy buildings that require little energy for space heating or cooling. The standard has gained popularity at the international level with cities like Kamakura, Japan, Whistler, Canada, Tramore, Ireland and Shanghai, China building structures based on the Passive House Standard. “The great potential of the concept has been recognized, especially in areas where actual practical experience has been gained with the implementation of Passive Houses,” says Prof. Dr. Wolfgang Feist who is the scientific director of the Passive House Institute and a building physicist at the University of Innsbruck in Austria. “The Passive House concept can be adapted to the various climates and regional construction methods and for this, the tools are available,” Feist explains. The Passive House Institute estimates that 20,000 Passive Houses have already been built worldwide, 13,500 of them in Germany alone.

In the plenary session, Burkhard Schulze Darup demonstrated how climate neutrality in the building sector can be achieved by the year 2050. Martin Treberspurg, Roman Smutny and Alexander G. Keul presented the results of the monitoring and user experiences from residential Passive House complexes in Vienna – where the measured energy consumption was reduced by two-thirds compared with new construction built according to national standards, even though the statistics do not even show an increase in the construction costs.

Energy efficiency and preservation of historical buildings

A separate Working Group dealt with the energy-efficient refurbishment of listed historical buildings in particular. Günther Gantioler, Christian Conrad, André Zaman and David Wohlgemuth presented their experiences with planning and implementation as well as the initial results of utilization. Improved thermal protection helps control problems caused by moisture build-up; in historical buildings, ventilation is of great importance for good indoor air quality and for controlling humidity. In short: high quality with regard to building physics means the best possible preservation of the protected building. If planned and carried out well, building preservation and high-level energy efficiency can be compatible.

Latest research and developments

Results of the latest scientific studies concerning the Passive House Standard were presented at the Conference. Benjamin Krick presented the criteria for the certification of curtain wall facades, the current requirements for the certification of skylights and the new efficiency categories for Passive House windows. The measured values from a refurbishment project using interior insulation were also presented. The focus was on the performance of conventional vapor retarders in comparison with moisture-adaptive vapor retarders. Jürgen Schnieders indicated approaches for restricting the moisture in basements after insulation of the basement ceiling in modernizations. Marc Großklos provided the answer to the question of optimizing both distribution losses and energy expenditure for hot water generation in Passive Houses: short and well-insulated pipework. Oliver Kah presented measurements results concerning the air quality in school buildings. It was shown that controlled ventilation in classrooms leads to a considerable improvement of the air quality in comparison with window ventilation. The previous recommendations by the Passive House Institute for the dimensioning of ventilation systems were thus confirmed.

Passive Houses – Globally

Passive House experiences in various climates were the topic of the Working Group for the “Global Passive House.” Christoph Begert presented solutions for the climatic conditions in Melbourne. Miwa Mori described the first certified Passive House in Japan and compared the Passive House standard with the requirements of the energy standards for buildings currently valid in Japan. Stefano Avesani presented a parametric study for the Passive House taking into consideration the various climatic conditions in Italy. Refurbishments have to be well planned: using concrete examples, Mario Bodem warned of ill-considered measures which can make it necessary to “refurbish refurbishments.”

Passive Houses in Central and Eastern Europe

The Passive House is putting regions into action: A panelist related how Bulgaria organized its first regional Passive House Conference in 2009 and established a network for the Passive House community. Progress is also being made in Latvia and Ervins Krauklis presented the first building in the country being constructed using Passive House components. Christina Victoria Ochinciuc from Romania presented a systematic analysis of energy and resource-saving construction. Pavel Kolacek reported about a two-storey timber building on a concrete basement in the Czech Republic that was built on the side of a hill. The construction of Passive Houses is subsidized by the national government and the Standard is gaining more and more attention from the public, as Jan Tywoniak reported. The experiences of residents of certified Passive Houses with passive cooling in Hungary were presented by Enikö Sariri-Baffia. A survey showed that passive cooling as found in Passive Houses is perceived as being more comfortable there than ordinary air conditioning systems. Günter Schlagowski presented a church and a sports hall built according to the Passive House Standard in Poland and concluded his presentation with valuable information about the dedicated Passive House community there. The extreme temperature differences in Croatia and their effects on the evelopment of the Passive House Standard in the region were also explained.