Permits are the least glamorous part of any renovation and the part most often skipped by homeowners hoping to save time and a few hundred dollars. That shortcut can cost far more than it saves, and understanding what actually requires a permit — which is narrower than most people assume, but non-negotiable within that range — avoids both the unnecessary paperwork and the real risk.
What typically requires a permit
Moving or adding plumbing fixtures, running new electrical circuits, structural changes like removing a wall, and anything affecting a home's water or gas lines almost always require a permit in most jurisdictions. A straightforward like-for-like swap — replacing a toilet in the same location, repainting, installing new flooring over existing subfloor — generally does not.
What it actually costs and takes
Permit fees vary widely by jurisdiction but are typically a few hundred dollars for a standard bathroom renovation, a small fraction of the overall project cost. The bigger cost is usually time: inspection scheduling can add anywhere from a few days to a couple of weeks to a project timeline, depending on how busy the local permitting office is, which is worth building into any renovation schedule from the start rather than treating as an afterthought.
What happens if you skip a required permit
Beyond the legal risk, unpermitted work creates real problems at resale — buyers' inspectors and lenders increasingly check for permit history on any renovated bathroom or kitchen, and unpermitted plumbing or electrical work can complicate a sale or trigger a costly retroactive permitting process. It can also affect homeowner's insurance claims if something goes wrong with unpermitted work down the line, since insurers can deny claims tied to work that should have been inspected and wasn't.
How to find out what your project actually needs
Most local building departments will answer a direct phone call about whether a specific, described project requires a permit, and this conversation is worth having before finalizing a renovation plan, not after. A good contractor will also know local requirements cold — if a contractor suggests skipping a permit that clearly should be pulled, treat that as a signal about how they handle the rest of the project, not just this one decision.
