Permits on a House Flip: What Needs One, What Is Exempt, and the Cost of Skipping It

Before the next kitchen, bathroom, electrical or roof task continues, write down the exact work and ask the local permit office about that scope. This checklist gives you a first screen. It does not replace the city or county rule that applies to the house.

Start with the adopted local code

The 2024 International Residential Code (IRC), section R105.1, is a model-code starting point, not an automatic rule for every U.S. house. It says an owner or authorized agent must first apply for and obtain a permit for covered construction, enlargement, alteration, repair, moving, demolition, occupancy changes, and regulated electrical, gas, mechanical or plumbing-system work. The local jurisdiction decides which code edition and amendments apply.

The same 2024 IRC section R105.2 lists work exempt from a permit, including painting, papering, tiling, carpeting, cabinets, countertops and similar finish work. It also says an exemption does not authorize work that violates the code or another applicable law or ordinance. That is why the label "like-for-like" is not enough: fixed wiring, piping, layout, structure and local amendments can change the answer.

A building permit, a contractor license or registration, and a specialty-trade credential are separate checks. Use the contractor-license guide alongside the local permit office's answer.

House-flip permit checklist

Examples from Rochester, NY and Portland, OR - verify your local rule before work. This is a comparison, not a nationwide permit chart. The cited city pages were checked October 20, 2026.

Kitchen

• Often permit-exempt in the cited examples: Rochester lists paint, finish work and cabinet/casework replacement that does not change layout. Portland lists cabinets.
• Often regulated - stop and check: moving walls or layout, new fixed wiring, changed plumbing, or an additional kitchen.
• Why the city matters: Portland exempts cabinets, but its Building Official Determination 19-06 says a new kitchen in a single-family dwelling needs a building permit. An additional accessory kitchen must meet the main kitchen's electrical, plumbing and mechanical code requirements.

Bathroom

• Often permit-exempt in the cited examples: Portland exempts removing and reinstalling a toilet solely for new floor covering. Rochester exempts replacement fixtures where fixed piping is not disturbed.
• Often regulated - stop and check: adding a bathroom, new fixtures, changed water or drain/waste/vent piping, or fixed wiring.
• Why the city matters: Portland says an added bathroom needs building and plumbing permits and may also need electrical or mechanical permits.

Electrical

• Often permit-exempt in the cited examples: Rochester separately lists replacement existing fixtures as exempt. It limits its exemption for directly interchangeable defective devices to work that does not disturb fixed wiring.
• Often regulated - stop and check: new wiring, circuit extensions, outlets, fixture additions, service equipment, or hard-wired system work.
• Why the city matters: Rochester lists new wiring, circuit extensions and fixture or outlet additions as permit work. Portland requires an electrical permit to install, change or repair a hard-wired system.

Roof

• Often permit-exempt in the cited examples: Portland exempts reroofing with similar-weight material, including some or all sheathing. Rochester exempts a repair affecting less than 50% of roof area.
• Often regulated - stop and check: a complete tear-off over conditioned space, structural frame work, a changed roof material, or a larger scope under the local rule.
• Why the city matters: Rochester's 50% threshold contrasts with Portland's similar-weight reroofing rule. The same "roof replacement" label can produce different local answers.

For the kitchen, bathroom and roof entries, see the Rochester building-permit guidance and Portland's residential permit checklist, checked October 20, 2026. For Portland's hard-wired electrical rule, see its residential electrical-permit page, checked October 20, 2026. Both cities show why a cosmetic description cannot settle a permit question.

If you have already started

Do not assume an after-the-fact permit has one national result. In Portland, City Code 24.10.060 allows a stop-work order requiring work to stop immediately and completely; written City approval is needed to restart. Portland's electrical enforcement rule allows investigation, correction requirements, civil penalties under applicable law, and an investigation fee for the City's added compliance-check cost. Rochester says required work cannot move to the next stage without required inspection and approval, and that late permits or missed inspections can cause delays or penalties.

Baltimore gives a more serious local example. Under Baltimore Building Code section 114, a person doing work without a required permit must stop, obtain the permit, and pay fees or penalties. The Building Official can require restoration unless compliant work is allowed to remain. The same section provides for a criminal fine of up to $500 per offense and, in a specified equity proceeding, a civil fine of up to $500 per day for unabated violations. Those are Baltimore rules, checked October 20, 2026, not a nationwide price list.

Example only, not a real property or a national fee benchmark: If a Miami permit's scheduled fee is $X, the City of Miami fee schedule, adopted April 23, 2026, says Homestead work begun before a required permit is 2 x $X + a $110 base fee. Its "all other properties (Commercial)" schedule is 4 x $X + a $110 base fee. Confirm the property's classification and the current schedule with Miami before using either multiplier.

Resale and insurance: document the answer you get

Unpermitted work can remain a resale issue even after the job is physically complete. California's 2026 Real Estate Law excerpts show that the statutory Real Estate Transfer Disclosure Statement asks covered residential sellers whether they know of alterations, repairs or modifications made without necessary permits and whether work did not comply with building codes. For a covered single-family-home offer accepted within 18 months after the seller took title, the same excerpts describe a separate contractor-improvement disclosure rule. When the seller contracted with a third party for covered improvements and was not provided copies of permits obtained, the seller may instead provide written notice and the third party's contact information. These are California disclosure examples, not a universal bar to sale.

In Baltimore, section 114 requires a transferee to obtain a violation report before transfer. When violation or condemnation notices are included, the transferee becomes primarily liable to abate them. Keep permits, approved plans, inspection records, invoices and contractor details with the deal file.

The cited sources do not establish an automatic insurance denial for unpermitted work. Coverage can be policy- and claim-specific, so ask the insurer how the actual scope and documentation affect the policy rather than promising a coverage outcome.

Five steps before work continues

1. Pause the affected work and write down the exact scope: finishes, layout, wiring, piping, structure and roof materials.
2. Check the city or county's adopted-code, building-permit and trade-permit pages. Do not use Rochester or Portland as your local answer.
3. Ask the permitting authority whether the exact scope needs building, electrical, plumbing or mechanical permits, and whether plans or inspections are required.
4. Check who may do the work and who must hold each credential. A permit does not replace a contractor or trade-license requirement.
5. Save the permits, approved plans, inspection approvals, invoices and contractor details for the resale file.

Before you make or revise an offer, add permit, inspection, correction, holding and contractor costs to the written deal budget. Choosing a house-flip offer multiplier shows where those known costs belong in the offer calculation.

This is general information, not legal advice. Permit, inspection, contractor, disclosure and insurance rules vary by state and locality. Confirm the exact scope with the permitting authority before work continues.