I want to add a room onto the back of my house. The permit office mentioned a plot plan. Do I need a surveyor?
Asked October 25, 2026
AI answer · not yet verified by a surveyor
Many permit offices require a site plan or plot plan showing the addition, the property lines and the setbacks. Whether it must come from a surveyor depends on your local rules [1].
A surveyor may be needed to:
- Show existing conditions: lines, buildings and easements, as a base for the plan.
- Confirm setbacks: prove the addition meets the required distances from the lines.
- Stake the location before footings are poured [2].
- Prepare a final or as-built survey if the city asks for one after foundation or final inspection.
An existing survey might be accepted if it's recent and nothing has changed [1].
Call the permit office and ask exactly what they need. If the addition will be close to a setback line, use a licensed surveyor so you don't have to tear out a foundation later.
General information only. Answers here are not a survey or legal advice, and no one here can tell you where your boundary is. For your property, hire a licensed land surveyor in your state; for legal questions, a real-estate attorney.