Most homes in the Oakland Hills are built on raised perimeter foundations. When a home inspector or a pest inspector makes an inspection they will often call out terms that don’t mean anything to the average Buyer or Seller.
The photo (above) details the components of your foundation from the floorboards down to the dirt beneath your home.
Many properties (such as the one in the photo) could benefit from some seismic upgrades/retrofitting. During an earthquake, seismic retrofitting helps the mudsill remain on the foundation (bolting,) the cripple wall studs from falling over (sheerwalls) and the floor joists from shaking off of the top plate (fasteners/clips.)
If you own a home that’s over 50 years old you would be well served by getting an earthquake resistance evaluation by a licensed engineer. I have several referral options for you if you’d like.