The house is a 2 story 1925 Craftsman bungalow and it looks like a foundation was re-built around 1960. It is a crawl space with 20in tall unreinforced 6in wide concrete block stem wall. The blocks appear to be in good shape, however, they are hollow. I found this out when I was drilling to install seismic bracing anchors. Do these blocks need to be reinforced somehow since i’m in seismic zone D1? Pics attached.
