Garage Conversions: Fontana vs Ontario
How do garage conversions rules compare between Fontana, CA and Ontario, CA?
Fontana and Ontario have similar restriction levels.
Fontana, CA
San Bernardino County
Fontana allows garage conversions with a building permit. ADU conversions under Gov Code 65852.2 need no replacement parking, while non-ADU conversions may require two off-street spaces.
View full Fontana rules →Ontario, CA
San Bernardino County
Ontario allows garage-to-ADU conversions under Gov Code 65852.2 with no replacement parking required. Non-ADU conversions to living space still need a building permit and must replace covered parking.
View full Ontario rules →Key Facts Comparison
| Fact | Fontana | Ontario |
|---|---|---|
| ADU path | 60-day ministerial approval under GC 65852.2 | - |
| Replacement parking | Not required for ADU conversion, may be for non-ADU | Not required for ADU |
| Building permit | Required for all conversions with structural and mechanical review | - |
| Minimum features | Kitchen, bath, heating, egress, smoke alarms for ADU | - |
| Wall replacement | Garage door must become permanent insulated wall | - |
| ADU conversion | - | Gov Code 65852.2 |
| Permit type | - | Building permit required |
| Egress | - | Bedroom window or door |
| Non-ADU conversion | - | Parking must be replaced |
Highlighted rows indicate differences between cities.
Fontana FAQ
Can I convert my Fontana garage into a rental unit?
Yes. An ADU conversion under state law lets you create a separate rentable unit with full kitchen and bath, and Fontana cannot require replacement parking.
Do I need permits to just turn the garage into a big bedroom?
Yes. Any conversion from garage to habitable space requires a building permit and must meet CRC standards for insulation, egress, and electrical.
Will I lose my parking if I convert the garage?
For ADU conversions, no - state law prohibits Fontana from requiring replacement parking. For non-ADU conversions, two off-street spaces may be required.
Ontario FAQ
Can Ontario make me add another parking space when I convert my garage to an ADU?
No. State law prohibits requiring replacement parking when a garage is converted to an ADU, even if the original garage provided the home's only covered parking.
Do I need a permit to turn my garage into a home gym?
Yes. Any conversion of garage space to living space requires a building permit, insulation, egress, and often a change-of-use review even if it is not an ADU.
Compare other topics
See how Fontana and Ontario compare on other ordinance categories.
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