Turning a Simi Valley garage into a bedroom or family room
Turn a Simi Valley garage into a bedroom, den or parent suite with a City permit: the structural work involved, the parking rule to check, and good uses.
Converting a garage to living space means the room becomes part of your house: a bedroom with its own bath, a den, a playroom or a suite for a parent. It keeps the same address and the same utility meters, and it does not get a kitchen of its own. That keeps it outside the ADU rules, which is simpler in most ways and stricter in one: parking.
The City of Simi Valley Building & Safety reviews it as a residential alteration. You need drawings, a permit, inspections while the work is open, and a final sign-off before the room counts as legal square footage.
What changes in the structure
The garage door opening is framed in with a wall that matches the house and sits on a proper footing. The slab usually needs a moisture barrier and a raised or leveled floor so the new room meets the house at the same height. Walls and ceiling get insulation and drywall, and the room needs windows for light and for getting out in an emergency, especially if anyone will sleep there.
The drawings also show where outlets, lighting and heating come from, and what happens to anything already in the garage, such as the water heater or laundry hookups. Those details carry most of the cost, so they are settled on paper before demolition starts.
The parking question for a living-space conversion
The state rule that waives replacement parking is written for ADUs. A garage converted into part of the main house is not an ADU, so Simi Valley's residential parking standards still apply. Ordinance No. 1349 (June 5, 2023) references Simi Valley Municipal Code section 9-34.040.B as the source of a home's required parking.
In practice the driveway, the lot and the City's reading of the code decide whether a living-space conversion works as drawn. If parking blocks it, converting to an ADU can remove the obstacle, because the City cannot require replacement spaces for a garage converted to an ADU (Gov. Code 66314(d)(11), HCD ADU Handbook, March 2026).
Uses that suit a living-space conversion
If the plan grows a kitchen and an outside door for a tenant, it has turned into an ADU, and that version is built through simivalleyaduconstruction.com. Without those, these are the common choices:
- A ground-floor bedroom and bathroom for a parent who can no longer manage stairs.
- A family room or playroom opening off the kitchen or hallway.
- A guest suite for visiting relatives, without a kitchen.
- A larger primary suite when the garage shares a wall with the bedroom wing.
Questions homeowners ask
Does a converted garage add square footage to my house?
Only once it is permitted and finaled. An unpermitted room is not legal living space, and appraisers and buyers' inspectors often flag it. The finaled permit is what makes the space count.
Can a garage bedroom have its own bathroom?
Yes, when the drawings show how it ties into the house's existing water and drain lines and the City approves them. A bathroom is common in a converted-garage suite and does not by itself make the space an ADU.
Will the front of my house still look like a garage?
Not if the new wall is designed with that in mind. The infill wall can take a window and stucco or siding to match, with a planter or walkway where the driveway meets it. If you have an HOA, its design approval comes before the City permit.
How long does a living-space conversion take?
Drawing the plans, City review and construction each take time, and review time depends on how complete the submittal is. Your schedule comes out of the walk-through, once the scope is known, not from a number on a website.
Sources
Facts on this page last verified: .
- California HCD, Accessory Dwelling Unit Handbook, March 2026: https://www.hcd.ca.gov/sites/default/files/docs/policy-and-research/adu-handbook-update.pdf (2026-10-05)
- City of Simi Valley, second reading of Ordinance No. 1349, staff memo of June 5, 2023: https://simivalley.granicus.com/MetaViewer.php?view_id=5&clip_id=2792&meta_id=204582 (2026-10-05)
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