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Garage conversion ADUs in Modesto

The slab, walls and roof are already paid for. We turn the space inside into a legal home with its own entry, kitchen and bath. Licensed and insured.

Check my garage Size rules

What happens in a garage conversion?

The shell stays and the inside changes. We add a kitchen, a bathroom, insulation, windows and a proper entry so the garage becomes a permitted dwelling. Reusing the slab, walls and roof is what keeps this type inexpensive.

If the garage is attached, it can also become a junior ADU instead.

Will the city make me add parking?

No. Under Government Code §66314(d)(11), as of October 2026, a city may not require replacement spaces when a garage, carport or other parking is converted or torn down for an ADU. The converted unit also needs no parking of its own.

Does the garage have to move back from the property line?

Usually not. The 4-foot side and rear setback is for new construction. A conversion can keep existing setbacks that are adequate for fire safety, and it can grow by up to 150 sq ft only to make room for an entry or exit.

What does a garage typically need to become a home?

An inspection of the slab and footings, then repair where they have cracked or sunk.
A vapor barrier and a finished floor above the concrete.
Insulation in the walls and ceiling to Title 24 levels.
Framing, a window and a door where the roll-up door was.
Fire-rated walls where the unit is close to the house or a lot line.
A load calculation on the electrical service, and often a new panel.
Drain lines to the sewer and a dedicated heating and cooling system.

Can the free regional plans be used for a conversion?

No. The county-and-cities plan set covers detached new construction. A conversion needs measured drawings of your existing garage, which we prepare as part of design and permits.

When should a garage be replaced instead?

It depends on its bones. A badly settled slab, short walls or termite damage can make repairs cost close to a new build. A garage built without permits may also raise questions; see our guide on unpermitted units. We inspect first and show you both paths in writing.

What does a conversion cost?

The nearest published 2026 figure, from Block Renovation's Sacramento guide, is $80,000 to $150,000, or about $150 to $250 per sq ft, as of October 2026. See the Modesto cost guide.

Find out if your garage qualifies

Share the address and a note about the garage. We look at its condition, the lot lines and the panel before any drawings.