Homes built before 1985 are more vulnerable to earthquake damage. Most homes built after 1985 were designed to conform to stricter building codes. These are probably equipped to resist the force of an earthquake. If your home is not built on a concrete slab or has a crawl space, chances are it’s built on a raised foundation. The supporting structure under a house with a raised foundation may not have been built to resist earthquakes. It could be subject to structural failure.
Homes built on a hillside often have raised foundations. These homes tend to have more severe failures. Why? The structural framing that supports the house is built at different heights.
Garage doors opening create vulnerable areas in a house. The narrow walls on either side of the garage door must be designed to resist earthquakes. This is important if there is a living space above the garage because of the added weight. Consult a licensed structural engineer if you have living space above a garage and your home was built before 1985.