Daniela Enz and Robert Hastings Architecture, Energy & Environment AEU GmbH Kirchstrasse 1, CH-8304 Wallisellen Tel. +41 -1 883 17 16 /17 daniela. enz@aeu. ch, robert. hastings@aeu. ch

To help architects plan very low energy housing for the first time, reference values can be useful for making critical decisions affecting performance. The authors have analyzed documentation from 20 Swiss projects built to extreme low energy standards, such as the Passivhaus and Minergie-P Standard. The results illustrate how Swiss house-builders have adapted German and Austrian Passivhaus concepts to local housing markets. The number of such high performance houses in Switzerland is still small but interest by home owners and subsequently by architects is growing. An initial sampling of the key values for the envelope and technical solutions are presented here. It is noteworthy, that for some key design parameters, a few projects lie quite outside the average, yet still achieve excellent energy performance by compensating in other parameters. This demonstrates that there is indeed considerable design freedom for engineering high performance housing.