Climate-Specific Passive Building Standards

Passive design principles (super insulation, airtight envelopes, elimination of thermal bridges, etc.) - pioneered in North America in the 70s and 80s and refined in Europe in the 90s have proven to be universally effective to significantly reduce heating and cooling loads. However, a single, rigid performance metric developed in Germany has led to limited uptake of passive building principles in many regions of the United States. It has also, in many cases, promoted some design decisions that had negative effects on economic feasibility and thermal comfort. This study's main objective is to validate (in a theoretical sense) verifiable, climate-specific passive standards and space conditioning criteria that retain ambitious, environmentally-necessary energy reduction targets and are economically feasible. Such standards provide designers an ambitious but achievable performance target on the path to zero. The second objective: develop simplified formulas for inclusion in a design and verification software tool that allow the generation of custom criteria based on specific climate and energy cost parameters for any particular location. The approach to arrive at this new set of criteria is to critically re-evaluate the current German-derived criteria in the light of issues discovered. A volunteer technical expert advisory council, the PHIUS Technical Committee (TC) has assisted the authors in the process and the results presented here reflect consensus votes by this volunteer expert body.