Nation’s first commercial Passive House retrofit becomes occupied Passive House office space

Glasswood Passive House retrofit, seeking PHIUS+ certification, becomes home to H&H’s building science corps.

It’s official.  Glasswood, the nation’s first commercial Passive House retrofit, is now an occupied Passive House office space.  The building science technicians of Hammer & Hand’s home performance team moved into the new space yesterday, and while some final trim work is being wrapped up, the office’s high performance systems are in place and humming along nicely.

Commercial passive house office retrofit by Portland/Seattle builder and remodeler.“It’s clear from the moment you enter the office that you’ve stepped into a truly modern building.  It’s bright, quiet, and full of fresh air,” said Skylar Swinford, building science guru with Hammer & Hand.  “It feels different, like a high quality building should feel.”

Built by Hammer & Hand and designed by Scott Edwards Architecture, the Glasswood project seeks PHIUS+ certification, the third-party-verified Passive House certification offered by the Passive House Institute US (PHIUS).  PHIUS+ rater Ryan Shanahan of Earth Advantage Institute has already conducted two PHIUS+ inspections, assessing the project’s air barrier and insulation, and conducting a preliminary blower door test to check airtightness.  A final inspection remains, including the final blower door test as well as the commissioning of the building’s ventilation and heating and cooling equipment.

Commercial passive house office retrofit by Portland/Seattle builder and remodeler.The independent, third-party verification of PHIUS+ certification is arguably the most important development in the US Passive House scene in the last year, and we were eager to use it at Glasswood (and at Karuna and Pumpkin Ridge, too).  The verification process (developed by PHIUS in partnership with RESNET) only ensures that certified projects actually perform at Passive House levels, it also makes Passive House projects eligible for a host of existing green building incentive programs across the country.  PHIUS+ therefore promises to help the Passive House standard gain real traction in the US marketplace.

Hammer & Hand is building the first floor of the Glasswood building as a new restaurant, Xico, co-owned by our very own Daniel Thomas.  Like the office above, the new space will also boast a high performance envelope and excellent indoor air quality, but because commercial kitchens consume and vent so much energy, the restaurant could never be a Passive House.  In order to pursue Passive House certification for the upstairs office space, the Glasswood team employed an oft-used and well-tested European Passive House strategy: define one portion of the building as the Passive House.

One advantage of this approach, particularly in a retrofit project (it’s harder to retrofit a high performance envelope than to build one from scratch) is that the restaurant space below provides a conditioned “adiabatic layer” that makes insulting the Passive House’s “foundation” much easier than if it were in contact with the ground.  Sound “creative”?  Perhaps.  But the approach has (rightly) been deemed kosher by the Passive House powers-that-be because it rewards high performance Passive House design and construction regardless of whether a project borders spaces (like commercial kitchens) that cannot feasibly become Passive House.

Glasswood represents an exciting development for us here at Hammer & Hand.  And while we’re proud of this first commercial Passive House retrofit in the US, we’re even more gratified to see our building science corps move into and inhabit the space.  Stay tuned for the coming open house!

– Zack

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