At more than 100,000 sq. ft., the CCSF Multi-Use Building is one of the largest applications of entirely passive heating and cooling. In the 18 months since its opening, we now have abundant performance data and are pleased at how well it’s exceeding expectations. Here’s how it works: Situated close to the Pacific Ocean, we took full advantage of the prevailing on-shore breezes, thereby providing passive, natural ventilation. Additionally, the five-story building manages temperature modulation using hydronic heating and cooling provided by a ground-source heat pump, which feeds off a series of on-site hydronic wells. A hydronic plant in the basement uses those the below ground pipes in these wells to produce both hot and cold water, effectively harnessing the temperature difference in the earth. The water pumped into the well returns at a different tempature and this tempature difference is harvested by the heat pump. This then is used to create controlled temperature water that is then circulated through the concrete slabs on each floor to create either heating or cooling. The result is a steady state, comfortable temperature throughout the building. Classrooms are positioned either side of a full-height and sky lit central atrium, which acts as the building’s “lungs” and a source of natural daylight. Warm air from each classroom exits into the corridor spine, flows upwards and exits through digitally controlled rooftop vents. This system completely eliminated the need for any conventional air-conditioning system.
A variety of system details ensure the building’s long-term performance, including sensors to monitor temperature and air flow and CO2 content on a room-by-room basis; custom louvered apertures to vent the air; and careful seals for both air and sound separation. The result is the building is 100-percent naturally ventilated (with exception for the bathrooms). To address noise concerns, we developed a series of sound-buffering strategies through choice of materials, and designing ducting to come up out of a room and then return downwards. Other sustainable elements for the building include low-emissivity (Low-E) window glazing to reduce heat loss and transfer; a vegetated green roof that reduces storm water runoff; and an integrated photovoltaic panel on the south canopy to generate electricity. Th building recently received a LEED gold certification.
I hope I’ll see some of you at the GreenBuild presentation on Thursday, Nov. 14, Moscone Convention Center South Building, Room 307, 9:30 a.m. If you can’t make it, I’ve posted a few photos so you can get a visual tour of the building, and more details are in on the project section of our website.