A typical retrofit completed by a licensed contractor may cost between $3,000 and $7,000 depending on the location and size of the house, contractor fees, and the amount of materials and work involved. If you are an experienced do-it-yourselfer, a retrofit can cost less than $3,000.
Once you've registered for the CEA BB program and choose to do the work yourself, you will identify yourself as an "owner-builder." As an owner-builder, you will be the general contractor for your project and assume responsibility for the overall job, including:
- Pulling building permits
- State and federal taxes
- Workers' compensation insurance and other legal liabilities
- Completing the retrofit in accordance with CEA BB Program Rules
- Passing final inspection
The Contractors State License Board provides a helpful Checklist for Owner-Builders (PDF).
Completing the Retrofit
You will be installing bolts into the foundation, and if one exists, installing plywood or oriented strand board (OSB) bracing along the stud wall (cripple wall) of your crawl space.
The CEA BB program adheres to the California Existing Building Code, Chapter A3. Chapter A3 is a statewide building code that sets prescriptive standards for seismic retrofits of existing residential buildings. Chapter A3 allows:
- A building department to approve the retrofit for a house with a 4-foot or shorter cripple wall, without requiring plans prepared by a licensed design professional (architect or engineer).
- Retrofits for houses with cripple walls that exceed four feet, but not taller than seven feet, with plans prepared by a licensed design professional.
- A prescriptive plan for a retrofit of houses that sit directly on their foundation (a "bolt-only" retrofit).
- A prescriptive plan for a retrofit of houses that have a short, wood-framed wall ("cripple wall") in the crawl space under the first floor, that needs to be strengthened to help prevent the house from sliding or toppling off of its foundation during an earthquake. Strengthening involves adding anchor bolts and plywood bracing in the crawl space (a "brace and bolt" retrofit).
Interested in learning more? DIYers are encouraged to view the FEMA Seismic Retrofit education videos that all licensed contractors complete before they can be added to the California Residential Mitigation Program's Contractor Directory, and that detail the steps for installation of retrofit components.
CEA BB also provides the following resources to help owner-builders understand the retrofit, allowable expenses, and track owner-builder receipts: