Garage Conversion ADUs in Santa Clarita

Why Garage Conversions Are Common in Santa Clarita

Drive any residential street in Saugus, Valencia or Canyon Country and you will see the same pattern: a house with an attached two-car garage, a driveway that already holds two cars, and a garage packed with storage rather than vehicles. That garage is roughly 400 square feet of enclosed, roofed space sitting on a concrete slab. No other square footage on the lot costs less to turn into a home.

State law treats a conversion of existing space as its own ADU category, separate from a new detached unit. That means a garage conversion does not use up your right to build a backyard cottage later. The city's handout says there is no maximum floor area for a conversion of an existing structure, and the unit only has to meet setbacks for fire and safety.

Garage Conversion Parking Rules in Santa Clarita

Parking is the question every owner asks first. Under state law, when a garage or carport is converted into an ADU, the lost spaces do not need to be replaced. The city's 2026 handout goes further and says it has no parking requirements for ADUs or JADUs at all on single-family lots.

That does not override your HOA's own rules about where cars may be parked. Some associations in the valley restrict street parking or require that garages be kept available for vehicles. California law limits how far CC&Rs can go in blocking ADUs, but parking rules are worth reading before you commit. We review them with you at the start. For the parcel's own driveway, two cars typically still fit in front of the old garage door opening, and tandem parking in a driveway counts under state rules wherever a space is required.

What Changes Inside a Converted Garage

A garage is built to store cars, not to house people, so a lot happens behind the drywall. The slab is usually a few inches lower than the house floor and often slopes toward the door; we either build up a new insulated floor or level it. Walls and ceiling get insulation to meet current energy code. The garage door opening is framed in with a wall, a window or a new entry door.

Plumbing is the big variable. Every sink, toilet and shower has to drain somewhere, and on a slab that means sawing trenches through the concrete back to the existing sewer lateral. Where the lateral runs, how deep it is and whether it has enough slope to reach the new fixtures all drive cost. Electrical service needs a look as well. A converted garage that becomes a full ADU will draw for cooking, heating, cooling and hot water, and many older homes in the valley still have a 100-amp panel.

• Insulated and leveled floor over the existing slab
• Garage door opening framed in with wall, window or entry
• New drain lines cut into the slab for kitchen and bath
• Electrical panel review and possible service upgrade
• Separate exterior entrance, as the city requires

Converting an Attached Garage: ADU or JADU

Owners with an attached garage have two paths. It can become a full ADU with its own bathroom and full kitchen, which may be rented with no owner-occupancy requirement. Or it can become a junior ADU of up to 500 sq ft, because for JADU purposes California considers an attached garage part of the home.

The JADU route allows a smaller efficiency kitchen and, if you want, a bathroom shared with the main house. Sharing sanitation triggers an owner-occupancy requirement, so most owners who plan to rent choose a full ADU instead. A detached garage at the back of a lot in Newhall is usually converted as a full ADU, since state law ties JADUs to the house itself.

Permits for a Garage Conversion ADU

Inside city limits, the conversion goes to the Planning Division first and then to Building & Safety for plan check, the same path as any other ADU. Drawings show the existing garage, the new layout, the plumbing route, energy compliance and the new exterior entry. Converting an existing accessory structure can include up to 150 square feet of expansion to accommodate ingress and egress, according to the city's handout.

Unpermitted garage conversions are a real issue in older parts of the valley. If a previous owner already turned the garage into a room without a permit, we can often bring it up to code and legalize it as an ADU, which is usually simpler than starting from a bare garage.