Passive, not complacent.
Passive House: not if, but how
Published: 27 May, 2009
FRANKFURT: Experts from over 50 countries attended the 13th International Passive House
Conference in Germany to debate the applications for this type of dwelling.
The 16 working groups dealt with topics such as climate protection policies, refurbishments, non-residential buildings and new applications of the Passive House standard.
In addition to the conference, the exhibition – with more than 4000 visitors converging on Frankfurt's exhibition centre, confirmed that Passive Houses are not exotic, but a building concept available to all.The implementation of the Passive House standard now appears on the political agenda. Experts and politicians used to ask whether this type of construction would prove itself as a building standard.
Facing the 16 500 accommodation units that have already been completed worldwide – of which around 12 500 are situated in Germany – the relevant question today is how the Passive House standard can be best applied.
"Motivation for this type of build comes from all over the European Union," explained Prof Dr Wolfgang Feist, director of the Passivhaus Institute (PHI) and professor at Innsbruck University.
"Almost all EU member states have Passive House initiative groups and have already completed their first demonstration projects. The idea has quickly spread around the globe,"
On behalf of the European Commission, EACI director Patrick Lambert presented EU projects dealing with the Passive House standard. The European Parliament prompted the European Commission to establish the Passive House as a mandatory standard for all new buildings that require heating and/or cooling.
At the opening session of the conference, environment minister of Hesse, Silke Lautenschläger, emphasised that the standard is an investment in the future, especially concerning the refurbishment of existing buildings.
"This is true, not only for complete renovations. An incremental refurbishment is also profitable with respect to reducing energy consumption. The basic principle for every component should be: 'If it's worth doing, it's worth doing well'," he said.
In Frankfurt, 1300 homes are expected to be built in Passive House standard by 2013.
During the last decade, 800 apartments, two schools and several day-care centres in the Passive House standard were built in the city.
According to the chief of the Energy Department of the city of Frankfurt, Dr Werner Neuman, this development resulted from the decision to invest in energy efficiency as well as the resolutions to make the implementation of the Passive House standard mandatory.
For many climates, the Passive House standard has already been demonstrated as viable, although in some regions, the components and/or research still needs to be improved. Micheal Lebau of Passive House Institute US, talked about how the climate zones in the US range from very cold and snowy regions in the far North, to dry and hot desert regions in the South West and hot and humid climates in the South East.
Jürgen Schnieders (PHI) showed how humidity recovery in ventilation systems influences a building's energy balance. As long as no additional ventilation is required for dehumidification, humidity recovery can reduce the heating demand by about 1kWh/(m²a). Franz Freundorfer (PHC) introduced a new window construction that combines low cost with a narrow elevation width and thermal insulation suitable for Passive Houses
The use of Passive House components in building refurbishment implies a significant reduction of costs. This was demonstrated by Dr Berthold Kaufmann (PHI) and Søren Peper (PHI) on the basis of the renovation project Tevesstrasse. Thanks to the complete renovation with Passive House components, of the 60 apartments originally built in the 1950s, the total heating demand according to PHPP was reduced by more than 90%, from 290 kWh/(m²a) to 17 kWh/(m²a).
Mark Siiddal (DEW JO'C Architects) showed how important it is to ensure windproof insulation and to seal the spacing between terraced houses.
Faulty implementation can easily double the heat losses, especially due to air circulation around insulation boards in multi-layered masonry.
Danny Parker (Florida Solar Energy Center) presented an innovative and cost-effective hybrid system for cooling and dehumidification, which makes use of the building's attic for radiation cooling during the night and for dehumidification with the daytime solar heat gains.
The International Conference presented a Passive Housetravelling exhibition, designed by the Passivhaus Institut. Display boards and design models offered easily understandable information about its principles. Solutions were presented both for new construction and for refurbishment of residential and non-residential buildings, including costs, incentives and examples.