The San Francisco Public Utilities Commission headquarters is a 277,500-square-foot, $146.5 million, 13-story office building that houses more than 900 employees. Completed in the summer of 2012, the building will use 32% less energy, 60% less water, and have a 50% smaller carbon footprint than similarly sized buildings.
Webcor Builders was the general contractor and self-performed the concrete work on the building. The public bid project sought a design that would remain functional after a large seismic event so the city could run fire and other disaster services out of the location. The owner also desired a building that could achieve LEED Platinum status and attain a 100-year lifespan. Webcor achieved this for not a dollar more or a day longer than other construction methods.
Using concrete as a structural design element helped Webcor achieve the owner’s desires. Webcor used 70% cement replacement mixes in the foundations along with smaller cement replacement mixes where strength gain was a factor. The result was a project-wide 50% cement replacement. Concrete’s long-term durability contributed to the 100-year lifespan. And the use of vertical post-tensioning in the concrete core walls will allow for the flexibility necessary in the case of a severe seismic event.
The building is an example of what can be attained with concrete as a construction material and where the standard for sustainable concrete construction is headed.
Other sustainable features of the building include:
- power from hybrid solar and wind turbine systems
- onsite treatment of gray and black water
- low-flow toilets
- urinals with a building-wide wastewater treatment
- rainwater harvesting system
- extensive use of recycled materials
The owner expects a $3.7 billion in ratepayer savings over the course of the building’s 100-year lifespan.
To read the full story, click here to download the Winter 2012 issue of Sustainable Construction.