Garage Conversions: Mountain View vs San Jose
How do garage conversions rules compare between Mountain View, CA and San Jose, CA?
San Jose has fewer restrictions than Mountain View.
Mountain View, CA
Santa Clara County
Converting a garage to living space or ADU in Mountain View is allowed with permits. State ADU law waives replacement parking when the garage is converted to an ADU.
View full Mountain View rules →San Jose, CA
Santa Clara County
San Jose allows conversion of an existing garage to an ADU or JADU under SJMC §20.30.150, consistent with California Government Code §65852.2. No replacement parking is required when an existing garage is converted to an ADU, and the existing setbacks are preserved for the conversion footprint.
View full San Jose rules →Key Facts Comparison
| Fact | Mountain View | San Jose |
|---|---|---|
| Permit | Always required | - |
| Min ceiling | 7 feet | - |
| Bedroom egress | Required | - |
| ADU parking | No replacement needed | - |
| Non-ADU parking | May be required | - |
| Code Section | - | SJMC 20.30.150; Cal. Gov Code §65852.2 |
| Replacement Parking | - | Not required |
| Existing Setbacks | - | Preserved for conversion |
| JADU Max Size | - | 500 sq ft (attached only) |
| Min Rental Term | - | 30 days |
Highlighted rows indicate differences between cities.
Mountain View FAQ
Do I have to add a driveway parking space?
Not when converting a garage to an ADU under state law; other conversions may require you to preserve required off-street spaces under local zoning.
Can I DIY the conversion?
Owner-builders can pull permits, but inspections and licensed electrical or plumbing subcontracts are required. Unpermitted work is cited on sale.
San Jose FAQ
Do I need to add a parking space if I convert my San Jose garage to an ADU?
No. State ADU law (Cal. Gov Code §65852.2), implemented through SJMC 20.30.150, prohibits San Jose from requiring replacement parking when an existing garage is converted to an ADU.
Can my San Jose garage become a JADU?
Yes, if the garage is attached to the single-family dwelling. A JADU is capped at 500 sq ft and must be within the walls of the primary home or its attached garage, with owner-occupancy required.
Do I still need a permit to convert a garage in San Jose?
Yes. San Jose Development Services requires a building permit for any change of use from garage to habitable space, even though the planning review is ministerial under SJMC 20.30.150.
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