Analysis and evaluation of structural additional costs for passive house projects

Status

completed

Abstract

Initial Situation

The success and market penetration of passive house technologies mainly relies - besides functionality - on additional building costs.

The additional building costs of various passive house buildings were already determined in the context of the CEPHEUS initiative. Passive houses constructed within this initiative were built between 1998 and 2001. The investigation of the additional building costs of newer passive houses gives an impression on how the costs for passive house technologies are changing over time.

Ambition

The aim of this research project is the consistent comparison of the additional building costs for passive house standards on four chosen building projects on one side and the contrasting juxtaposition of these four buildings with the passive house demonstration projects of the CEPHEUS initiative on the other side. A statement on the range of the momentary additional building costs for passive houses can therefore be made. Furthermore, the development of the additional building costs will be demonstrated through comparison with the CEPHEUS projects from a few years ago.

Content and methodology

Over the course of this project, the additional building costs of four chosen apartment passive houses were investigated. As a benchmark for the investigation of the additional costs of the building, the low energy standard as defined by the housing funding association was used.

The components relevant for the passive house technology, e.g. the external wall or the window, were examined independently and the arising additional costs were separately calculated.

To ensure comparability between the additional building costs of the individual projects, the buildings with conventional heating systems were calculated with air supply heating.

It shall be recognisable how the building costs have changed over the past years, therefore an index validation has not been performed.

Results and conclusions

The Viennese passive houses with a completion date between 2006 and 2010 investigated in this project demonstrated that a passive house standard can be achieved with additional building costs of 4 % to 6 %. The additional building costs of the passive houses of the CEPHEUS initiative built between 1998 and 2001 lay between 0 % and 17 %, in average 10 %, respectively.

The comparison demonstrates that the additional costs of the passive house building standard sank rapidly over the past few years. The reason for this is the expertise and a continuous development of passive house technologies. Additional costs of less than 6 % are feasible for a variety of passive house projects from technical planners with relevant knowledge, as this report demonstrates, emphasising the cost effective details of the newer projects.

Project manager

DI Helmut Schöberl, Schöberl & Pöll OEG