ADU Electrical Panel Requirements in Los Angeles
Planning an Accessory Dwelling Unit (ADU) in LA? Here is what you need to know about main panel sizing, 100A subpanels, dedicated LADWP meters, and LADBS permit compliance.
Main Panel Capacity: 100A vs 200A Upgrades
Before adding an ADU, your electrician must perform a load calculation per NEC Article 220. Most older homes in Los Angeles have a 100-amp main breaker. Adding an ADU with electric HVAC, cooking, and water heating usually requires upgrading your main electrical panel to 200 amps or 400 amps.
Subpanel vs. Dedicated LADWP Utility Meter
When wiring an ADU, property owners have two primary options:
- 100A Subpanel (Fed from Main House): Most cost-effective option. Powers the ADU directly from the primary electrical panel.
- Dedicated Utility Meter (Dual Socket): Best for rental ADUs. Requires installing a dual-meter socket adapter and coordinating directly with LADWP or Southern California Edison (SCE).
2026 California Electrical Code & LADBS Permits
All ADU electrical work in Los Angeles requires permits from the Department of Building and Safety (LADBS). Key 2026 CEC requirements include:
- Dedicated AFCI and GFCI circuit breaker protection throughout the unit.
- Underground rigid conduit running from main house to detached garage/ADU.
- Title 24 solar-ready electrical infrastructure.
Need an ADU Electrical Inspection & Estimate?
AMY Electric provides complete ADU electrical wiring, subpanel installation, and LADBS permit handling across Greater Los Angeles.
☎ Call (818) 302-5614