20th Street Residence is a minimal home located in San Francisco, USA, designed by SF-OSL. The client came went to the architects with a derelict home on 20th street by Potrero Hill. The clients had a basic need for an upgrade but also more space – to achieve this it became evident that expanding up through the roof was the only way. This would not only meet their needs, but could potentially take advantage of the view overlooking the San Francisco Bay.