Do I need a permit for an ADU or garage conversion?

Short answer: Across the 25 US cities we checked, an ADU or garage conversion always needs a permit in 11, needs none in 0, and depends on size, location or scope in 0; 14 are unverified. Your city's rule is what counts.

11 permit required
0 depends
0 no permit
14 unverified
0 fees verified

Adding an accessory dwelling unit or converting a garage to living space is a change that needs building permits and zoning review in practically every city.

General pattern only, not a rule for any city. The table below is built from each city's official source.

City-by-city comparison

ADU or garage conversion permit rules by city
City	Answer	Key condition	Fee
Austin, TX	Permit required	Zoning review applies	Not verified
Boston, MA	Unverified, confirm locally	We did not find an official Boston page on ADU or garage conversion permits that we could quote.	Not verified
Charlotte, NC	Permit required	Plan review required	Not verified
Chicago, IL	Unverified, confirm locally	We did not find an official Chicago page on ADU or garage conversion permits that we could quote.	Not verified
Columbus, OH	Unverified, confirm locally	We did not find an official Columbus statement on ADUs or garage conversions; room additions and garages need	Not verified
Dallas, TX	Unverified, confirm locally	We did not find an official Dallas page on ADU or garage conversion permits.	Not verified
Denver, CO	Permit required	Licensed contractor required	Not verified
El Paso, TX	Unverified, confirm locally	We did not find an official El Paso page on ADU or garage conversion permits that we could quote.	Not verified
Fort Worth, TX	Permit required	Zoning Board variance may be needed	Not verified
Houston, TX	Permit required	Structural, flood and planning review	Not verified
Indianapolis, IN	Unverified, confirm locally	We did not find an official Indianapolis page on ADU or garage conversion permits that we could quote.	Not verified
Jacksonville, FL	Permit required	Yes. Garage conversions are alterations that need a building permit.	Not verified
Las Vegas, NV	Permit required	Plans required	Not verified
Los Angeles, CA	Unverified, confirm locally	LADBS lists ADUs among common permits, but we did not find an official page we could quote on their requiremen	Not verified
Nashville, TN	Permit required	Yes. Converting an attached garage to living space, or building a detached ADU (DADU), needs a building permit	Not verified
New York City, NY	Unverified, confirm locally	We did not find an official NYC page on ADU or garage conversion permits that we could quote.	Not verified
Oklahoma City, OK	Unverified, confirm locally	We did not find an official Oklahoma City page on ADU or garage conversion permits that we could quote.	Not verified
Philadelphia, PA	Unverified, confirm locally	We did not find an official Philadelphia statement on ADU or garage conversion permits that we could quote.	Not verified
Phoenix, AZ	Permit required	Detached ADU: new building permit	Not verified
San Antonio, TX	Unverified, confirm locally	San Antonio has an ADU permit program, but we did not confirm its requirements from an official page we could	Not verified
San Diego, CA	Permit required	See IB-142	Not verified
San Francisco, CA	Unverified, confirm locally	We did not find an official San Francisco page on ADU or garage conversion permits that we could quote.	Not verified
San Jose, CA	Permit required	ADU plan review	Not verified
Seattle, WA	Unverified, confirm locally	We did not find an official Seattle page on ADU permit requirements that we could quote.	Not verified
Washington, DC	Unverified, confirm locally	We did not find an official DC page on ADU or garage conversion permits that we could quote.	Not verified

Other projects

Not legal advice. Always confirm with your local building department. Rules change, and your parcel's zoning, HOA, historic district, floodplain or utility work can change the answer. We show the official source and the date we last checked it so you can verify for yourself.