Selling a House With Unpermitted Work: Risks and Options

How Unpermitted Work Comes to Light

There are several routine ways buyers find unpermitted work:

• Permit searches. Many cities publish permit records online, and buyers' agents increasingly check them. How to Look Up Building Permits for a House shows how easy it is.
• Home inspections. Inspectors notice new mechanical equipment, a finished basement, or an addition that does not match the record.
• Appraisals. Appraisers compare square footage with public records; unpermitted living space may be valued differently.
• Insurance and lenders. Underwriters may ask about recent work, especially roofs and electrical systems.
• Listing photos. A listing that advertises a new bathroom or a "bonus suite" invites questions.

Why It Matters to Buyers

Unpermitted work is not automatically bad work, but nobody has checked it. Under the IRC, inspections (R109) exist so that concealed work such as framing, wiring and plumbing is seen before walls are closed. Without that record, a buyer cannot know whether the work meets code, and the new owner inherits the problem. Under IRC R113 and R114, the building official can treat work without a permit as a violation and order work to stop.

For a buyer the practical risks are repair costs, difficulty insuring or financing, and the cost of legalizing later. Those risks usually show up as a lower offer, a credit, or a request that the seller fix the issue before closing.

Your Three Options as a Seller

1. Disclose and Price It In

Some sellers disclose the work, provide whatever documentation exists (contractor invoices, photos taken during construction), and accept that buyers will factor it into their offers. This is often quickest, but expect a narrower pool of buyers.

2. Legalize It With a Permit After the Fact

Most building departments let you apply for a permit for work already done. The process typically involves submitting an application (and plans where required), opening walls or ceilings so inspectors can see concealed work, correcting anything that fails, and passing a final inspection. IRC R108.6 allows the building official to charge an additional fee for work started before a permit was issued; the amount varies by jurisdiction. For a new dwelling unit, Seattle notes that units are not legal unless established through a permit, and that legalizing an existing unit requires a construction permit to establish the use.

3. Remove or Restore It

If the work cannot pass, or legalizing costs more than it adds, the work can be removed and the space returned to its permitted condition. Removal of some items, such as electrical or plumbing, may itself need a permit.

Disclosure: Know Your State's Rules

Seller disclosure requirements are set by state law and vary widely: some states use mandatory disclosure forms that ask directly about permits, others follow a narrower standard. We do not summarize state law here because the details matter and change. Before listing, ask your agent for your state's disclosure form and consult a real-estate attorney if you are unsure. Concealing known defects can create legal exposure after closing.

Steps to Take Before You List

1. Pull your own permit history. Compare it with every project done since you bought the house, and ask the previous owner's records if you have them.
2. Make a list of gaps. Note the work, roughly when it was done and who did it.
3. Talk to the permit office. Many offer free advice; Seattle offers free 20-minute permit coaching. Ask what a retroactive permit would involve.
4. Get contractor input. A licensed contractor can estimate what opening up and correcting the work would cost.
5. Decide with your agent whether to legalize, remove or disclose and price.

If You Are the Buyer

Look up the permit history before you make an offer, ask the seller for documentation of major projects, and have your inspector flag anything that looks newer than the record. How to Read a Building Permit Record explains what a finaled permit looks like versus one that was opened and never closed. An open, expired permit can be as much of a problem as no permit at all.

Keep Good Records Going Forward

After any project, save the permit, inspection results, contractor invoices and product information in one place. When you eventually sell, a complete file answers buyers' questions before they are asked, and shows that work was done properly.

Building Departments in the Cities We Cover

Rules in this guide vary by jurisdiction. These are the official departments that issue residential permits in the 15 cities we track, with the city's open-data source for permit records. Each city page shows the rules for roofing, HVAC, solar, fence and deck work.

Before relying on any rule, read the department's current page or call its permit desk. Model-code sections cited here (such as IRC R105) are adopted locally, often with amendments.

Frequently Asked Questions