Buy & Sell FAQs · Permits + zoning
Permits, zoning and unpermitted work.
How to check what is legal on a property, and what to do when something is not.
How do I look up the permit history for a property?
Search the permitting agency's records for the parcel. In unincorporated Sonoma County that is Permit Sonoma's permit record search; inside a city it is that city's building department. Records show issued permits, inspections and finals, and gaps in the record are as informative as entries.
Older records are sometimes incomplete or held only on paper, so an absent record is not always proof that work was unpermitted.
SourcePermit Sonoma · permit record search (opens in a new tab)
What counts as unpermitted work?
Any construction, conversion, addition or system change that required a permit and did not receive one; work under a permit that was issued but never finalled is a related problem with its own cure. Common examples are converted garages, enclosed patios, added bathrooms, barn conversions, decks, and electrical or plumbing work done without inspection.
A permit that was issued but never finalled sits in an awkward middle ground and usually still needs resolution.
SourcePermit Sonoma · Building Division (opens in a new tab)
Can unpermitted work be legalized after the fact?
Often yes, through a retroactive or as-built permit process. The work has to be brought to current code, which can mean opening walls for inspection, upgrading systems, or redesigning elements that were acceptable when built. Some work cannot be legalized because it violates zoning, setbacks or density.
Get a scope and cost estimate from the building department and a contractor before deciding whether to legalize, disclose and sell, or remove.
SourcePermit Sonoma · Building Division (opens in a new tab)
Who is responsible for unpermitted work, the buyer or the seller?
The seller must disclose what they know. Once the sale closes, the obligation to resolve it generally sits with the new owner, because code enforcement follows the property rather than the person who did the work.
That is why the cost of legalization belongs in the price negotiation rather than in a hope that it never comes up.
SourceCalifornia Civil Code 1102.6 · Transfer Disclosure Statement (opens in a new tab)
What is the difference between zoning and the general plan?
The general plan sets long-range land-use policy for an area. Zoning implements it with specific rules for a parcel: permitted uses, density, setbacks, height and lot coverage. When the two conflict, the process to resolve them is a planning matter, not something a property owner can assume in their favor.
Read both for the specific parcel. A general plan designation that suggests future potential does not grant present-day rights.
SourcePermit Sonoma · zoning and land-use parcel search (opens in a new tab)
Can I build an ADU on my property?
State law requires local agencies to permit accessory dwelling units in most residential and mixed-use zones, subject to objective standards for size, setbacks, height and parking. Local constraints on septic capacity, water supply, fire access and hazard zones still apply and can be decisive.
Confirm the current local ordinance for the specific parcel, since local standards are updated frequently to track changes in state law.
SourceCalifornia HCD · accessory dwelling units (opens in a new tab)
How long does a permit take in Sonoma County?
It ranges from over-the-counter for simple work to many months for projects needing planning review, environmental review, septic design or agency referrals. Complexity, completeness of the application and the number of departments that must sign off drive the timeline more than anything else.
An incomplete application is a common cause of delay. Ask what a complete submittal looks like before filing.
Do I need a permit for a deck, fence or shed?
It depends on size, height and attachment. Many jurisdictions exempt small detached sheds and low fences, while decks above a certain height, anything attached to the house, and any structure with electrical or plumbing generally require permits.
Thresholds differ between unincorporated county and each city, so check the jurisdiction that actually governs the address.
SourcePermit Sonoma · Building Division (opens in a new tab)
What is a nonconforming use?
A use or structure that was legal when established but does not comply with current zoning. It can usually continue, but expansion, reconstruction after damage and periods of discontinuance are typically restricted.
Legal nonconforming status is worth confirming in writing, because rebuilding rights after a fire or a loss often depend on it.
Do permits from the county carry over to a city?
Jurisdiction follows the address. If a property is inside city limits, the city permits and inspects it; if it is in the unincorporated county, the county does. Annexation can change which agency holds current authority even though older records sit with the previous one.
For any property near a city boundary, confirm the governing jurisdiction before searching records.
Will unpermitted square footage count in an appraisal?
Not reliably. There is no fixed rule: the appraiser has to identify the work, judge its quality and legality and decide what the market pays for it, and the lender's program rules decide whether it can count toward living area at all. An unpermitted addition can therefore raise your cost and your tax exposure without raising the appraised value proportionally.
Lenders vary in how they treat it, so if financing depends on the square footage, verify with the lender early.
SourceFannie Mae Selling Guide · improvements section of the appraisal report (opens in a new tab)
How do I check for open or expired permits?
Search the permit record for the parcel and look for permits issued without a final inspection. Open permits can delay or complicate a sale and its financing, and require reinspection of work completed years earlier.
Resolving an open permit takes time and sometimes construction, so find it before you list rather than during escrow.
SourcePermit Sonoma · permit record search (opens in a new tab)
What is a lot line adjustment or a parcel split?
A lot line adjustment moves a boundary between existing legal parcels. A subdivision or parcel split creates new parcels. Both come with zoning minimums, access, water, septic and environmental requirements, and neither is guaranteed by parcel size alone. Most are discretionary reviews; the exception is a qualifying SB 9 urban lot split in a single-family zone, which the agency must process ministerially if the parcel meets the statutory tests.
Land marketed as splittable should be treated as a question to verify with the planning department, not a fact.
SourcePermit Sonoma · zoning and land-use parcel search (opens in a new tab)
How do I confirm a property is a legal parcel?
Through the planning department, using a certificate of compliance or an equivalent determination. Historic descriptions, separate assessor parcel numbers and old deeds do not by themselves establish that a parcel is legally created and separately buildable.
This matters most for rural land, split-off pieces and anything with an unusual ownership history.
Nothing matches that. Try a shorter phrase, or just ask Steve.
General answers about California and North Bay practice. Not legal, tax or insurance advice, and none of it describes a specific property. Rules change, so check anything that matters with the agency or professional named.
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