Most of the brick buildings in San Francisco have been seismically upgraded per Ordinance 92, and Double-D Engineering has been the go to firm for these majestic buildings. Our most recent UMB upgrades is an old Fire House in Russian Hill. It required all the typical elements of a seismic upgrade- steel frames, concrete shearwalls, plywood diaphragms, parapet bracing, and seismic roof and floor ties.