NAPHN19

Passive House buildings in mixed-humid climates such as NYC face several unique challenges when compared to buildings which are in a heating-only or a cooling-only climate. This session will seek to review the technical and design aspects central to effective PHPP energy modeling for buildings in these difficult climates. Employing good passive measures to design out overheating AND over-humidification are critical to ensuring good occupant comfort and low energy consumption. For humid climates in particular, good mechanical design and modeling are key to avoiding potential humidity problems during operation. 

The presenters will present an overview of the PHPP’s cooling calculations, demonstrate the critical inputs and look at how to interpret and understand the model results. Using case-studies this session will illustrate how designers can use the PHPP energy model to ensure good manual ventilation, effective window shading and how to control interior humidity. Real-world monitored results will be shared to illustrate common issues with some types of Passive House mechanical systems and how to address these concerns. In addition, options for additional shading factor calculations will be demonstrated, as well as in-depth review of the PHI ‘Heat Pump’ tool which is critical for Passive House projects seeking certification with these increasingly common cooling systems.