Søren Peper
Bibliographic info:
9th International BUILDAIR Symposium, 8-9 May 2015 Kassel, Germany

Content of the presentation

Several rehabilitation projects of apartment buildings all used passive house components, but implemented different airtightness designs. Two projects (24 and 52 apartments in Ludwigshafen and Frankfurt am Main, respectively) were carried out in the traditional way, using the interior plaster in the area of the external walls. The airtightness layer of another project in Nuremberg was implemented on top of the old exterior plaster layer. This presentation will analyze the different designs and their consequences. It will also examine the different approaches in the floor and roof areas.

The final airtightness measurements of the three retrofits document their success, resulting in a median n50 of n50 = 0.45 or 0.35 h-1. For two of the buildings, airtightness before the renovation had also been documented, showing even more clearly the great potential for improvement.

The example of a single-family home in Zellingen, Bavaria, additionally shows how necessary it is to come up with an airtightness design early on, especially in the case of a gradual retrofitting process. The lack of an airtightness design in the first rehabilitation phase (roof) led to a persistently average airtightness. This could not be completely remedied in the later rehabilitation phases, confirming the importance of said design.

The second part of the presentation will introduce the rehabilitation standard EnerPHit. In order to achieve optimum thermal insulation standards when retrofitting buildings, the Passive House Institute started the EnerPHit certification at the beginning of 2010. “Optimum” thermal insulation standard in this context means significantly improved energy efficiency in comparison to the legal requirements while providing excellent cost-effectiveness for the thermal insulation measures in general. At the same time, EnerPHit modernizations offer the additional benefits of using passive house components, including a high level of thermal comfort, avoidance of structural damage, and optimum indoor air quality. The purpose of the certification is above all to offer builder-owners a guaranteed high-quality and cost-efficient modernization through quality assurance. They can be sure that the above-mentioned optimum thermal insulation is actually achieved and the implemented measures do not fall short. This becomes even more important considering that later “improvements” of inadequate thermal insulation measures are almost always inefficient.


For more information, please contact the reference author at: soeren.peper@passiv.de