The primary heating system for the large studio spaces is a large rooftop array of hydronic solar collectors feeding a radiant slab distribution system, with additional hydronic heat storage in the form of a large tank which becomes a interesting object within the cafe area.

Engineering intuition was used to estimate if the natural ventilation level would be sufficient. The team left what was there and hoped for the best, assuming that the building was leaky enough. When the refinished windows were found to seal better than expected, some additional operable windows were added to make up the ventilation shortfall.

In retrospect, there aren't any parts of the system the designers feel are undersized. They think the exhaust fan type, chosen to allow reverse to blow in warm roof air during the winter, may have been overkill, since the performance of the solar-heated floor slab negated the need for that ceiling air re-circulation. The packaged system provided particularly for the gallery system may be overkill.

Rooftop HVAC mechanical equipment at the CCA SF building. Photo: Kevin Matthews Rooftop HVAC piping at the CCA SF building. Photo: Kevin Matthews This floor-level cabinet houses equipment for the radiant floor heat distribution system. Photo: Kevin Matthews Click on thumbnail images to view full-size pictures.