Selling a house with unpermitted work in California is a situation the state's main disclosure form asks about directly. Mid-century homes have had five to seven decades to collect changes, and not every owner pulled a permit for an enclosed carport, a rear addition or a new bathroom. The work itself may be sound; the missing paperwork is what needs a plan.
This guide explains what the law asks sellers to disclose, the three main paths (disclose and sell, legalize, or remove), what California's ADU law offers for unpermitted units, and how buyers' lenders look at it. It's general information, not legal advice. Talk with a real estate attorney about your situation and with your city's building department about its process.
Find out what was permitted
Start by comparing the house to the record. Pull the permit history from your city's building department and walk the house with it. In a mid-century home, the items to check include:
A carport or atrium that's been enclosed
A rear addition or a bump-out that changed the footprint
A bathroom added or a laundry moved
A converted garage or a detached unit in the yard
Electrical panel, roof or heating changes
Some cities offer online permit searches. Palo Alto's Permit View, for example, searches building, planning and code enforcement activity by address or parcel number. If records look thin, ask the building department how to request older files. When the house and the paperwork don't match, write down what you know: what was done, when, and by whom.
What California requires you to disclose
The Real Estate Transfer Disclosure Statement asks whether the seller is aware of room additions, structural modifications, or other alterations or repairs made without necessary permits, and of any not in compliance with building codes. The form says it isn't a warranty and isn't a substitute for inspections.
Three more points shape how you handle it:
Disclosure can't be waived. Civil Code Section 1102 says any waiver of the disclosure article's requirements is void as against public policy. Selling "as is" doesn't remove the duty to disclose what you know.
Quick resales carry an extra disclosure. Under Civil Code section 1102.6h, added by AB 968, a seller who accepts an offer on a single-family home within 18 months of taking title must disclose room additions, structural modifications, and other alterations or repairs made since then by a contractor the seller hired, name the contractor for jobs above a small dollar threshold, and provide copies of any permits the seller obtained. It applies when the seller accepts an offer on or after July 1, 2024.
Disclose what you know, not what you guess. If you aren't sure whether something was permitted, say what you know and point buyers to the records.
Disclosure rules have details and exceptions, so have a real estate attorney review anything you're unsure about.
Three ways to handle unpermitted work
1. Disclose and sell as is. You disclose the work, provide the records you have, and let the buyer decide how to treat it. This avoids construction before the sale, but the buyer is likely to factor the open question into an offer, and their inspector and lender may look closely.
2. Legalize it with a permit. Ask the building department what it needs to permit existing work. The city may ask for drawings and an inspection of the work, which can mean opening finishes to show framing, wiring or plumbing. Costs and fees vary by city. San Francisco, as one example outside the South Bay, sets the penalty for work without a building permit at nine times the issuance fee plus the original permit fee, calculated from the work already done, according to its Notice of Violation page (checked November 2026). Ask your own city how it handles fees for work already done. A permit can also trigger other requirements: in a single-family home built on or before January 1, 1994, a permit applicant making alterations must replace noncompliant plumbing fixtures with water-conserving ones.
3. Remove or restore it. Sometimes the cleanest answer is to undo the work, such as reopening an enclosed carport or atrium. Removal can need its own permit, so check first. For mid-century homes, restoring an original feature can also bring the house back toward its design. Our Eichler renovation guide and design guidelines page help you think through that choice.
Unpermitted ADUs: what state law offers
If the unpermitted work is a backyard unit or a converted space used as an accessory dwelling unit, California's ADU law has a specific path. According to the Department of Housing and Community Development's ADU fact sheet, AB 2533 (2024) amended Government Code Section 66332 to help legalize unpermitted ADUs and junior ADUs built before January 1, 2020, while ensuring the structures won't be substandard. It limits fees, allows a third-party code inspection and requires local jurisdictions to inform the public about its provisions. HCD notes that, as of January 1, 2026, the same text is numbered Section 66311.7.
The details are set by state law and applied by your city, so ask the planning and building departments how they handle these requests before you list.
How buyers and lenders look at it
A buyer's lender orders an appraisal, and Fannie Mae's Selling Guide addresses this directly: if the appraiser identifies an addition that doesn't have the required permit, the appraiser must comment on the quality and appearance of the work and its impact, if any, on the market value of the property. (New appraisals submitted on or after November 2, 2026 use a redesigned appraisal dataset with its own Fannie Mae policy supplement, so ask the lender whether anything differs.) Good workmanship and clear documentation can help that comment.
A buyer's inspector may also note signs of unpermitted work, such as wiring that doesn't match the rest of the house or framing that doesn't line up with the original structure. The better your records, the fewer open questions the buyer carries into negotiations.
When you set the price, account for the work honestly. Square footage in an unpermitted addition, the cost to legalize, and the buyer's perceived risk all belong in that conversation with your agent. Our selling assistance page explains how we work through it with sellers.
Build a disclosure package
Permit history printout and any finaled permits
Contractor invoices, contracts and license numbers for work you had done
Dates and photos of the work, if you have them
Any correspondence with the building department
Pre-listing inspection and pest reports that describe the affected areas
Our seller resources cover the rest of pre-listing prep.
Frequently asked questions
Can I sell a house with unpermitted work in California?
Yes. California's disclosure law centers on telling buyers what you know: the Transfer Disclosure Statement asks about work done without permits or not in compliance with building codes, and that duty can't be waived. Whether to legalize, remove or disclose and sell as is depends on the work and your city.
Do I have to disclose unpermitted work done by a previous owner?
The disclosure form asks what the seller is aware of. If you know about work a previous owner did without a permit, disclose it along with what you know about it. A real estate attorney can advise on specific facts.
Can I legalize an unpermitted ADU before selling?
Possibly. AB 2533 created a path for unpermitted ADUs and junior ADUs built before January 1, 2020, with limits on fees and an option for a third-party code inspection. Ask your city how it handles these requests and how long the process takes.
Will the city make me remove unpermitted work?
It depends on the work and the city. Some work can be permitted after the fact with inspections and fees; some may need changes or removal. The building department is the place to ask, ideally before you list.
Related reading
Sell a House As Is in California: Original Mid-Century Homes
Selling a Mid-Century Modern Home: What to Fix and What to Leave
Selling a mid-century home with work that predates your permits, or your ownership? Call or text the Boyenga Team at (408) 373-1660 or (650) 383-8606, or contact the Boyenga Team to talk through your options. For legal questions about disclosure, consult a real estate attorney.
