Historic Phius Retrofit: putting together beauty, function, building science, and efficiency for a net-zero house

July 24, 2023

What An Architect DoesAirtightnessDecarbonizationEco DesignFrom the FieldGreen ArchitecturePassive House ArchitectureZero Energy

Historic Phius Retrofit: putting together beauty, function, building science, and efficiency for a net-zero house

We’re excited to be in construction on our first historic residential Phius retrofit. Typical of these “firsts” (and most our works, thankfully), this project started with an inspired owner, whose vision was to update the old (1902) house in line with modern ideas about space, energy, technology, and health. Since it needed updating to the extent of a gut remodel, we had the opportunity to set the home up for the next century.

This kind of thinking is a key strategy for the best, fastest path to net zero emissions by 2050: radically reducing energy use of old buildings with only a modest upfront embodied energy input is needed in communities like Oak Park, where the greatest share of greenhouse gas emissions comes from heating our old, leaky buildings. Tearing down and building new is not such a viable strategy, as it requires huge amounts of upfront embodied energy in materials, while throwing away the old material.

Unlike cars, whose shape and construction materials have modernized significantly from the early 20th c., most homes are still constructed like this one: concrete foundation, wood framing, brick and stucco cladding. The overall mass, window area, and orientation are passive in nature since the home was built before large mechanical systems were a viable option. There are some significant changes, though—here’s what’s different:

Putting all this together with energy modeling and third-party quality control during construction allows us to pursue the Phius certification. By meeting the stringent metrics and QC, the owners are ensured optimal performance for the life of the building.