First Reinforced Concrete Building on West Coast
Portland’s Balfour-Guthrie Building, designed in 1913 by Morris Whitehouse—the same architect responsible for the design of the Oregon State Capitol— represents somewhat of a milestone in the concrete industry. It was the first office building on the West Coast to be constructed with reinforced concrete. At the time, the material was mainly used for bridges and industrial structures, and was just beginning to gain acceptance as a construction method for everyday-use buildings. However, the loss of a few other Balfour-Guthrie properties (including the company’s San Francisco office, which was destroyed by fire in the 1906 earthquake), combined with the timely opening of their Bellingham cement plant, may have influenced the company’s decision to pioneer the use of reinforced concrete as a fireproof building material in this setting.
It is fitting, then, that a renovation of this historic building would also heavily incorporate the use of concrete. When Thomas Hacker Architects (THA) undertook in 2001 a $1.5-million restoration of the structure that would eventually house their offices, they sought to maintain the character of the original building while adding energy-efficient features that would take it into the 21st century. Seven layers of lead-based paint were stripped from the exterior to reveal the original sandstone, and more than 500 sandstone blocks were individually anchored to provide a seismic upgrade.
Inside, THA opened up the floor plan, carving out 900 square feet of the original first-floor concrete slab allowing light into the basement level, and creating additional office space. Doing so exposed the original concrete aggregate, reinforcement, and other structural elements that dated back to the initial construction. Drag strut was reinforced to work in conjunction with existing concrete columns, and concrete window panels poured in two lifts formed a solid background for the original double-hung wood windows. Plywood panel form boards were used to visually separate the new concrete work from the existing hardwood board formed concrete.
The renovation marked another concrete milestone for the historic structure when it became the first LEED® Silver certified architectural office in the United States. To achieve this distinction, the design team added a host of energy-efficient features to the building including insulating storm windows, a heat-reflecting Energy Star roof, day lighting controls, and low-flow, water-conserving fixtures. Seventy-five percent of the construction waste was salvaged, and 58 percent of the wood used came from Forest Stewardship Council U.S. (FSC-US) certified forests. Low-toxic, low-volatile organic compound (VOC) materials were chosen for the interior, and for added safety, the structure was flushed with fresh air for two weeks prior to occupancy. Its location in the city’s core allows 75 percent of its occupants to take alternative transportation to work, and the restored Balfour-Guthrie Building further pays homage to the environment by welcoming it in, via operable windows, natural day lighting, and views of the North Park Blocks in downtown Portland.
The project is a true testament to concrete as a sustainable solution and the durability and flexibility of concrete enabled the structure to be re-used in a cost-effective manner. The building, which has served many for almost 100 years, is now poised to continue to serve for another century without disruption to the environment.