Composting Toilets: Lessons Learned

The Bullitt Center was designed to show what’s possible. It is exploring scores of new ideas in an effort to push architects, engineers, developers, and bankers to ever-greater levels of environmental performance. Before the Center was built, for example, every developer interviewed by the project team asserted that it would be impossible to generate as much electricity from sunlight striking the roof of a six-story office building in Seattle, WA as the building and its tenants would need. However, calculated on an annual basis, the Bullitt Center has been a net-positive energy building since its opening in 2013.

Once something exists, no one can claim that it is impossible.

“The Bullitt Center is a giant science experiment,” said Denis Hayes, CEO of the Bullitt Foundation and leader behind the project. “We integrated lots of bleeding-edge technologies. If everything had worked perfectly, that might have meant we hadn’t been bold enough.”

It is in this context of experimentation and learning that the Bullitt Center decided to remove the composting toilet system from the building, replacing it with a highly water-efficient vacuum flush system connected to the municipal sanitary sewer system.

The following white paper offers insights into this decision, as well as lessons learned, to inform other teams as they consider composting toilet systems in their own projects.

Learn more by downloading the white paper here.