Electrical and HVAC Addition Cost across San Diego County
Electrical and HVAC work for a garage conversion runs $8,000-$25,000 in San Diego County, covering everything from a simple subpanel and mini-split up to a full panel upgrade and new electrical meter for a full ADU.
What moves the price
- Whether the main panel needs a full upgrade or just a new subpanel
- Ducted HVAC extension vs. a standalone mini-split system
- Distance from the main panel to the converted garage
- Whether the ADU needs its own electrical meter (full ADU only)
What's included
- Subpanel or dedicated circuit installation
- Mini-split or ducted HVAC unit sized to the space
- Outlets, switches, and lighting circuits
- Panel upgrade if the existing service cannot support the new load
- Permit-required electrical and mechanical inspections
Common questions
Does a garage conversion always need a panel upgrade?
Not always. If the existing panel has open breaker slots and enough amperage headroom, a subpanel can often be added without a full service upgrade. An electrician confirms this with a load calculation before the estimate is finalized.
Is a mini-split cheaper than extending the main HVAC system?
Usually yes for a single-room conversion, since a mini-split avoids running new ductwork through the attic or under the slab. A full ADU with multiple rooms sometimes makes more sense with a small dedicated ducted system.
Do I need a separate electrical meter for an ADU?
Not required by California ADU law, but some homeowners choose a separate meter to track ADU utility usage separately, especially if the unit will be rented. It adds cost and requires utility company coordination.
Need a written electrical cost for your project?
Insured local crews across San Diego County put the scope in writing.