Bisnow Goes to the Bullitt Center

After our Seattle's Green Building Revolution event, Unico Properties director of sustainability Brett Phillips, one of our speakers, was good enough to give Bisnow a personalized tour of the greenest of Seattle properties, the Bullitt Center.

The Bullitt Center, which Unico manages, achieved Living Building Certification earlier this year, a rare distinction, but more recently it also achieved something else every building wants: 100% occupancy. Brett tells us the building's tenants are every bit as concerned with the environment as the Bullitt Foundation and Unico. He's snapped with the property's engineer, Corey Reilly, who offered insights on the building he's been running for more than a year.

First things first: the foam toilets, which are an integral part of the building's composting system. When the toilets sense a user, they begin to emit foam. This foam, consisting of a biodegradable soap-like substance and about three tablespoons of water, slides down the vertical tubes, creating a low-friction lining so all the waste goes down to the composters. Since the Bullitt Center runs on composters and isn't hooked up to the methane-producing sewer system, it's OK to use a standard pipe that goes straight down to the composters (just be careful not to drop your iPhone down it).

In fact, the Bullitt Center is the tallest building ever to implement a composting system for its sewage. Pictured here are the composters in the basement that handle solid waste (liquid waste has its own tanks). These aerobic systems are more common in one-story buildings and in places that don’t have access to sewer lines. The challenge was to develop a delivery system from the higher floors that would safely bring the waste down to the composters.

The building also captures rainwater. Below the structure's well-known hat of solar panels, a parapet roof captures rainwater and brings it to downspouts that carry the water to a 56,000-gallon concrete cistern in the basement. On its way down, the water is funneled through a vortex filter, which removes large particulates. To create the potable water, the rainwater is then ultra-filtered through three ceramic filters (pictured), with the finest removing viruses. The rainwater is also passed under ultraviolet light and through activated charcoal.

The Bullitt Center is heated (and cooled) by a dense system of hydronic radiant tubing that coils a few inches beneath the concrete overlay of each floor (we couldn't take a picture of that directly, but Corey and Brett are standing on such a floor in the creatively design space). Formally known as “cross-linked polyethylene,” the tubes are otherwise called PEX. Inside them, a special mix of water and glycol runs quickly, warming or cooling the concrete slab, which efficiently radiates into the occupied areas.

They look like an ordinary openable windows—which would have been unusual in the sealed up office buildings of the '70s or '80s—but it's really more sophisticated than that, Brett tells us. A digital controller operates the windows, as well as the interior and exterior shades, in response to exterior conditions, to manage both glare and heat gains. There's an override button to allow the occupants to open the windows, but only within a certain range of indoor and outdoor temperatures.  

Across the street: a weather station that helps the building's systems (such as the windows) respond appropriately to current conditions. There are more instruments on the Bullitt Center's roof as well.

That's only a sampling of the Bullitt Center's sustainable tech. It also has the very visible solar panels that generate more electricity than the building uses, a highly developed building management system, graywater use, a design that encourages use of the stairs, and more. Finally, there's the waste bin on the first floor. Not remarkable otherwise, but it's the only one in use for the entire 52k SF building. The recycling ethic is so strong at the Bullitt Center that Brett says it takes a whole week to fill up the regular waste bin, if not longer.