On a corner in a historic district in downtown Portland, Oregon, a new office building has just started what could be a very long tenure. If its builders got everything right, it will still be standing there five centuries from now.
The 5-story, 58,000-square-foot mixed-use commercial building was specifically designed to last 500 years—with a super strong structure, resilient design, and a suite of on-site infrastructures that will allow it to make its own power, harvest its own water, and adapt to huge swings in the climate for centuries to come. Designed and partly developed by ZGF Architects along with PAE Engineers, also the main tenant, its rents cost only about 8% more than a conventional office.
The building has been designed to meet the standard of the Living Building Challenge, a green-building-certification system that’s regarded as one of the most difficult to achieve. Prioritizing designs that have net positive impacts on the environment, Living Building Challenge buildings create more energy than they use, clean and reuse water, and absorb more carbon dioxide emissions than they produce. It’s a high bar, and one typically met by only high-end homes or large-scale trophy buildings for organizations with deep pockets, including several Google offices, a sustainable design center at Georgia Tech, and the headquarters of the Bullitt Foundation in Seattle.
For the project in Portland, the developers aimed to show that modest-sized buildings could be built to the standard in a way that hit all its environmental goals while also penciling out financially. Part of making it work was stretching the building’s longevity as far into the future as feasible.
Paul Schwer, president of PAE Engineers, says that a 500-year horizon wasn’t on the table when the planning first started for this new office building. But the more he looked at the project, the more sense it made to create a building able to withstand the biggest natural disasters and disruptions. “Structural engineering codes are there for life safety, which means after a big earthquake, everyone will be able to get out of the building safely,” he says. “I’m thinking with my investor hat on. So if we have a big one, and we’re in the Cascadia earthquake zone, we lose our entire investment? That seems crazy.”
The building’s structural design was upgraded to the same sturdiness as many hospitals, firehouses, and police stations. That decision was pivotal to its financial feasibility. Because the building was now being designed to be sturdier and wobble less during a big earthquake, its edges could be built a few inches closer to the property line and the neighboring buildings on two of its sides. Adding just a few inches to the building’s width and length created an additional 208 square feet of floor area to the entire building. And though it cost about $135,000 extra to upsize the building, the added floor space will result in an estimated $150,000 in additional rent over the course of its first decade.
Other longevity-focused design solutions include a building façade made of durable masonry, and windows and insulation designed to enable the building to withstand extreme weather fluctuations in the coming decades and centuries.
The building’s resilience has also been prioritized. All wastewater treatment happens on site, and the building has a 71,000-gallon cistern in which to store rainwater. A ventilation system uses both manual and computer-controlled window openings to regulate the interior temperature with little or no heating and cooling. A system of photovoltaic panels and onsite batteries enable the building to operate off the grid for up to 100 days. These systems combine centuries-old building techniques with modern materials and systems, according to Kathy Berg, a partner at ZGF Architects.
“It’s ancient thinking from the perspective of really stepping back and thinking about climatic response, but it’s also constantly looking forward and constantly using today’s technology to figure out how to solve that,” she says.
These sustainability features also ended up pushing the design in interesting directions. As the client and main tenant of the building, PAE Engineers had wanted to include a roof deck for events and company happy hours, but water and energy needs got in the way. “With a building that’s trying to capture all of the water that lands on it and grab as much solar access as they can, we needed every inch of that roof,” Berg says.
So the designers came up with a compromise. Instead of a roof deck, Berg and her team created what she calls a “deckony”—a top corner of the building that can open up its walls to the elements as a kind of indoor-outdoor deck/balcony. It provides a social space for lunch, informal meetings, and Friday afternoon drinks at its built-in bar. “It could have been a corner office. Instead, PAE wanted to make it a corner for everyone,” Berg says.
Being an office for an engineering company that focuses on buildings, this project also has a few features not commonly seen in other offices. Schwer says the bathrooms all have airplane-style vacuum-flush toilet systems that use 90% less water than typical toilets, and the in-house composting system processes waste into fertilizer. The building even uses separators that divert urine into a special area where it is converted into highly valuable fertilizer. “We’re planning on selling about $50,000 a year of liquid fertilizer from what every other commercial building considers a waste stream,” he says. Things like this will ultimately help offset the cost of the building, which Schwer said was about 25% higher than a typical office building.
Selling urine may not be on most developers’ agendas, but Schwer says it’s all part of ensuring the project makes financial as well as environmental sense. He says there’s no reason other developers couldn’t mimic this project in other cities. Planning around climate resilience and a very long-time horizon, he says, should start to become a more common way for developers to build in cities. And nearly every system and material in the building can be easily found on the market. “You don’t have to be a Google, you don’t have to be a Georgia Tech, you don’t have to be a Bullitt Foundation to do these,” he says.