Homeowner's Guide to Earthquake Safety
Published by the California Seismic Safety Commission. Required disclosure reading for buyers and sellers of one-to-four unit residential property built before modern seismic codes.
Why This Guide Matters
Earthquakes are inevitable in California and can occur at any time without warning. This guide, developed by the California Seismic Safety Commission under Business & Professions Code §10149, helps homeowners identify potential structural and non-structural risks, understand retrofit options, and meet California disclosure law.
When a home built before 1960 is sold, the seller and the seller's agent must deliver this guide and disclose known seismic deficiencies under California Civil Code §1102.6 (the Residential Earthquake Hazards Report).
Common Earthquake Hazards
Most earthquake damage to houses results from a handful of well-understood weaknesses. Knowing them helps you evaluate risk and prioritize repairs.
| Weakness | Description | Typical Risk |
|---|---|---|
| Unbolted foundation | House frame not anchored to the concrete foundation | Sliding off the foundation |
| Weak cripple walls | Short wood stud walls in the crawl space are unbraced | Collapse of the first floor |
| Soft first story | Living space over a garage or open wall lacks lateral bracing | Story collapse |
| Unreinforced masonry | Brick chimneys, walls, and foundations without steel reinforcement | Falling debris, wall failure |
| Unbraced water heater | Tank can topple and rupture gas or water lines | Fire and water damage |
Strengthening Your Home
A seismic retrofit reduces the chance of costly damage and injury. The most cost-effective improvements for older wood-frame homes include:
- Bolting the wood sill plate to the foundation with anchor bolts or foundation plates.
- Bracing cripple walls with structural plywood sheathing.
- Strapping the water heater to wall studs and using flexible gas/water connectors.
- Reinforcing or replacing unreinforced masonry chimneys and foundations.
- Securing heavy furniture, cabinets, and appliances to prevent tipping.
Financial & Insurance Resources
The California Residential Mitigation Program's Earthquake Brace + Bolt (EBB) program offers grants toward qualifying retrofits. Standard homeowner's policies do not cover earthquake damage; separate earthquake insurance is available through the California Earthquake Authority (CEA) and private insurers.
Seller Disclosure Obligations
- Deliver this guide to the buyer for homes built before 1960 (and it is recommended for all homes).
- Complete the Residential Earthquake Hazards Report disclosing known weaknesses under Civil Code §1102.6.
- Disclose the property's location within an Alquist-Priolo Earthquake Fault Zone or Seismic Hazard Zone as part of the Natural Hazard Disclosure Statement (Civil Code §1103).
Bottom Line
Older wood-frame homes are especially vulnerable but also the most cost-effective to retrofit. Sellers must disclose known seismic deficiencies and hazard-zone status; buyers should factor retrofit costs and earthquake insurance into their decision.