Understanding and materializing a client's vision is central to the stated philosophy of Seattle-based design firm, Weber Thompson. This credo was expressed clearly when the firm decided to design its new headquarters—an office intended to reflect its vision. The Terry Thomas provides a window into the soul of a firm that practices what it preaches and whose approach to sustainability is as much rooted in common sense as it is in the eco-enthusiasm of its employees. Expected to earn a LEED Core and Shell Gold rating from the Washington, D.C.-based U.S. Green Building Council, the building’s straightforward green features are integrated into the décor. The Terry Thomas stands as an example to clients, tenants and the community.
Long a resident of Seattle’s South Lake Union neighborhood, Weber Thompson was fast outgrowing its leased office space, which was in a building with a 1980s design and an antiquated HVAC system. As the firm grew to include more than 80 employees, it became clear that a new space was needed.
“When the decision to relocate came up, we conducted a series of discussions and surveys within the office,” recalls Peter Greaves, AIA, LEED AP, principal at Weber Thompson. “The two most consistent and highest-rated points were for daylighting and natural ventilation. Those concepts really drove the design and construction of this building.
COOL LIKE THAT
With the mandate of the firm’s employees, the decision was made to build a new office that would rely completely on a passive cooling system, using natural airflow to regulate the building’s temperature. “We wanted to continue the sustainable-design approach we’ve been doing with our clients and walk the talk,” Greaves remarks. “It’s one thing to do this work for your clients; it’s another to push the envelope and do it yourself. The Terry Thomas probably is the first non-air-conditioned office built in Seattle in 50 years.”
Weber Thompson occupies 25,000 square feet (2323 m2) of the 40,000-square-foot (3716-m2) Terry Thomas building. The structure is built around an open-air courtyard and has operable windows on all four faces. A series of louvers, controlled by temperature and carbon-dioxide sensors, operate in tandem so the courtyard and outside faces open together and create natural airflow. Heating comes from a hot-water perimeter baseboard system. The building’s structural system uses concrete slab, which has the thermal capacity to hold heat in the winter and coolness in the summer.
“Mechanical engineers did a great deal of thermal modeling for us. They were able to determine what our comfort level will be in this building,” says Scott Thompson, AIA, LEED AP, senior principal for Weber Thompson and lead principal of the Terry Thomas project. “As it turns out, the inside temperature will exceed 85 F [29 C] approximately 18 to 21 hours per year. In Seattle, that’s typically going to happen in the late afternoon. It’s one of those things we’ll have to adapt to; if that means people come in earlier and leave earlier a few days a year, that’s what we’ll do.”
This small concession doesn’t appear to be an issue for other tenants, either. All but one small office space and one commercial space already are filled, and there are letters of intent from prospective tenants for those two remaining spaces.
While this unconventional approach to cooling, which makes no use of traditional air-conditioning systems, raised a few eyebrows during construction, Weber Thompson was confident in its collective decision. “We held our ground,” Thompson says. “It is a critical component of this building. Seattle has a temperate, mild climate with very low humidity—there’s no reason we can’t build this kind of structure here.”
The other main item on the firm’s wish list, daylighting, is evident everywhere in the new headquarters. With the building’s courtyard design, floor plates are only 36-feet (11-m) deep, allowing an abundance of natural light into the office. White interiors, open studio spaces and low-height office walls add to a strategy that makes the most of available daylight.
As with the thermal aspects of the building, extensive modeling was done to determine the proper approach to lighting the interior. Part of the challenge was to find a way to use as much available sunlight as possible without overly impacting the building’s internal temperature. A series of shading systems were the key to walking this thin line.