Hillside Foundation Repair and Earthquake Retrofits in Orinda, CA

01At a glance

Orinda homes at a glance

1960

Median year built

94.6%

Single-family detached homes

91.3%

Owner-occupied

19,507

Residents (2025 est.)

Housing figures: U.S. Census Bureau ACS 2020–2024; population: Vintage 2025 estimate (QuickFacts).

02Steep lots

Houses on piers and tall downhill walls

Where lots fall away steeply, houses are often supported on concrete piers, stepped footings or tall cripple walls on the downhill side. Those conditions change both kinds of work:

• Repairs usually mean drilled piers and grade beams designed from a geotechnical report. How hillside repairs work →
• Retrofits on tall or stepped walls often go beyond the prescriptive plan and need an engineer's design. Retrofit scope →

03Geotechnical reports

Why the geotech report comes first

The report sets how deep supports need to go and whether drainage, retaining or tiebacks are part of the fix. USGS has documented landslides on ancient deposits across the county's hills (USGS Bulletin 1388); EQ Zapp shows mapped zones for an address. Ask for the report before comparing hillside quotes; see who does what.

04Permits

Permits for Orinda and Moraga

Building permits for Orinda are reported to be issued through Contra Costa County; confirm with the City of Orinda before planning. Moraga uses the County for plan check and inspection (County building permits). Grading on steep lots can add review time.

05Moraga

Moraga, next door

Moraga's housing is a little newer (1972 median build year) with more mixed foundation types, but its hillside streets raise the same questions. ZIP 94556: check Brace + Bolt eligibility with CRMP's lookup.

06Brace + Bolt

Brace + Bolt in ZIP 94563

Orinda's 94563 was on the 2025 eligible list; the grant pays up to $3,000 toward a code-compliant retrofit of a qualifying pre-1980 raised-foundation house (CRMP). Hillside houses may fall outside the prescriptive plan. Eligibility checklist →

09Questions

Orinda questions