This presentation will explore how Passive House (PH) residential projects perform relative to California’s 2025 Title 24 Energy Code by comparing the Passive House Planning Package (PHPP), WUFI Passive, and California’s CBECC compliance software across all 16 California climate zones for illustrative single-family and multi-family prototypes. It encompasses a structured comparison of how the same Passive House-related design strategies are represented across modeling platforms, where assumptions can be aligned, and where differences in software structure, input options, or compliance rules affect modeled outcomes. The resulting diagnostic comparison and recommendations are intended to improve consistency between Passive House and Title 24 assessments and better recognize high-performance enclosure and ventilation strategies within California’s existing compliance pathways, while supporting California’s evaluation of Passive House standards and compliance pathways under AB 368.
Learning Points:
- Understand how Passive House and 2025 Title 24 homes compare in site energy, peak demand, and modeled compliance outcomes across California’s climate zones.
- Discuss how Passive House and Title 24 simulation tools value efficient design strategies differently.
- Identify where there is opportunity for Title 24 compliance tools and documentation practices to evolve to better reflect measured performance while maintaining enforceability.
- Explain the impact of certain measures, such as infiltration, on modeled results of the same design across different modeling tools.
Presenter: Becca Evans
Becca has a background in Mechanical Engineering and has been at Frontier Energy for the past three years. She provides support for building energy code development through Codes and Standards Enhancement (CASE) and Reach Code work for single family and multifamily applications. She has recently led analysis on comparing Passive House and Title 24
