Your existing policy probably does not cover your ADU correctly
Most California homeowner policies are written for single-family residences. Once you add an ADU, you typically need to update your coverage in three ways.
1. Increase your dwelling coverage
Your insurer needs to know the ADU exists. Replacement cost on a typical 600 sf ADU runs $200k–$350k — add this to your dwelling limit.
2. Add landlord (loss-of-rent) coverage if renting
If you rent the ADU, add fair rental income coverage so insurance pays your missing rent if the unit becomes uninhabitable.
3. Update liability limits
A tenant injury can trigger a major liability claim. Raise your liability from typical $300k to at least $500k (umbrella policies often add $1M cheaply).
What to tell your insurer
- ADU square footage and bedrooms
- Whether attached or detached
- Whether you plan to rent (and to whom)
- Construction type (wood frame, etc.)
- Year built
Cost impact
Adding a permitted ADU typically increases your annual homeowner policy by $250–$700, depending on rental status and coverage limits.
What gets denied
- Damage if you did not disclose the ADU to your insurer
- Tenant injury if liability limits are too low
- Unpermitted ADU repairs after damage
Frequently Asked Questions
Do I need separate insurance for my ADU?
Usually not — most California insurers add ADU coverage to your existing homeowner policy as an endorsement.
How much does adding ADU coverage cost?
$250–$700/year additional premium for typical permitted ADUs.
Does the tenant need renter's insurance?
Recommended and often required in lease — tenant's renter's insurance covers their belongings and liability.
What happens if my ADU is unpermitted?
Most insurers will not cover unpermitted structures and may deny claims.
Should I get an umbrella policy?
Highly recommended if you rent the ADU — $1M umbrella typically costs $200–$400/year.
Related Vision ADU Resources
- How to Build an ADU, Day 1: Architecture & Design
- How to Build an ADU, Day 2: Structural Engineering
- How to Build an ADU, Day 3: Title 24 Energy Compliance
- How to Build an ADU, Day 4: City Submittal & Permits
- ADU Contractor in Anaheim
- ADU Contractor in Huntington Beach
- Los Angeles County ADU Builder
- Orange County ADU Builder
- Inland Empire ADU Builder
- 2026 ADU Cost Calculator
- All Vision ADU Service Areas