Nihonmachi Terrace is a high density Japanese senior housing complex in San Francisco Japan Center. The existing courtyard consisted of a lawn and a few trees that provided open space for the tenants and visitors. Kwan Design Architect (in association with Robert La Rocca Landscape Architect) revitalizes the courtyard in response to Japanese garden design principals, natural features and sustainable design solutions. The new courtyard included rock garden with raked gravel, pathways and wooden bridges over a dry creek, plants indigenous to the mountains, water scriptural feature, community vegetable garden, windbreak elements and gathering opportunities.
This project is located within the 65 CNEL Aircraft Noise Footprints based upon the Federal Aviation Administration (“FAA”) 1983 CNEL Noise Exposure Map. If the properties within this map is constructed after Jan. 1st 1983, or is renovated at a cost equal to 25% or more of the current market value of the home, it must be insulated against aircraft noise to meet FAA noise insulation program standards. This means that the windows must have a Sound Transmission Class (or STC) rating of 35. A typical interior wall with one layer of 1/2″ gypsum board on each side of wood stud at 16” on center has an STC of approximately 33.
The window manufacturer we selected cannot provide STC 35 certification as a whole window assembly but the glass itself will perform the STC rating of 30 – 35. We explained the situation with the building official and were able to obtain approval with the glass specification.