How to Legalize Unpermitted Work: Getting a Permit After the Fact
To legalize unpermitted work, you apply for a permit after the fact: you document what was built with as-built drawings, submit them to the building department like a new permit, open up walls or ceilings if inspectors need to see hidden work, fix anything that doesn't meet code, and pass final inspection. Most unpermitted additions, garage conversions and basement finishes can be legalized; work that breaks zoning rules or can't be made safe may have to be removed.
Why legalize unpermitted work
Unpermitted work can block a sale, cause insurance claims to be denied, reduce appraised value and lead to fines if the city finds out. Legalizing it removes the risk and lets you count the space in the home's official square footage. See what happens if you build without a permit.
Step 1: Find out what was permitted
Request the property's permit history from the building department. Compare the approved permits and drawings with what exists today, so you know exactly which work needs legalizing.
Step 2: Prepare as-built drawings
The application needs drawings of the work as it exists, usually a site plan, floor plans, elevations, and structural and MEP information. Our guide to as-built drawings explains what's included. If the work doesn't meet current code, the drawings also show the corrections you'll make.
Step 3: Apply and get inspected
The city reviews the drawings like any permit. Inspectors then check the work, and may ask you to:
- Open drywall to show framing, insulation, wiring or plumbing
- Expose footings or provide a structural evaluation
- Upgrade smoke and CO alarms, egress windows or electrical panels
- Pay permit fees, sometimes with a penalty multiplier
When work can't be legalized as built
If the work breaks zoning rules, such as building inside a setback or over the height limit, you may need a zoning variance or have to modify or remove it. Basements without proper egress or ceiling height may need changes; see basement conversion requirements.
Getting help
ArchPermits prepares as-built and permit drawings for legalizing unpermitted additions, garage conversions, ADUs and basements nationwide. See our permit drawing services.
Frequently asked questions
Can unpermitted work be legalized?
Usually, yes. Most unpermitted additions, garage conversions and basement finishes can be legalized with a retroactive permit, as-built drawings, inspections and any needed corrections.
What is a permit after the fact?
A building permit issued for work that was already done without one. The city reviews as-built drawings and inspects the work before approving it.
What makes work unpermittable?
Work that violates zoning rules, such as setbacks, height or lot coverage, or that can't be made safe or code-compliant, may not be approvable as built and may need a variance, changes or removal.
Do I need drawings to legalize unpermitted work?
Yes. Most cities require as-built drawings showing the existing work, plus any corrections needed to meet code.
Have a project that touches on this? Browse all our permit drawing services, delivered in 24 hours to 7 days nationwide, or the full permitting resource library.
Get Your Permit Drawings Started — Free Estimate
Tell us about your project and we'll tell you exactly what your permit drawings need to include, and a realistic timeline — no obligation.
Get a Free Estimate