Plat of Survey
A surveyor-prepared drawing that documents lot boundaries, existing structures, and easements.
Applies to
Accessory structures · Additions · Decks · Fences · Pools · Property-line work
Project example
A homeowner may find a survey in the closing packet, but a later patio or addition can make its existing-conditions layer incomplete for a new permit.
Also called
Where this term shows up in permit work and how it affects the project
The plat supplies the boundary facts used to verify setbacks, easements, lot dimensions, and coverage. An outdated or illegible copy can leave the reviewer unable to confirm placement.
If this term appears in a form, plan comment, or local ordinance, start with the building permit guide, compare it against the zoning permit guide, then use the permit guide directory to find the right local path.
Why plat of survey matters in a permit file
A plat of survey records measured property facts. It is different from a site plan, which adds the proposed project. Many permit offices use the survey as the base because a fence, curb, aerial image, or tax map is not a boundary determination.
Where it appears in the permit process
Pre-design
The survey establishes lot lines, dimensions, recorded easements, and visible improvements before the footprint is chosen.
Site-plan preparation
The proposed work is commonly drawn on a clean copy of the survey.
Zoning review
Staff uses the measured boundary and structure locations to check setbacks and coverage.
Property disputes or irregular lots
A new or updated survey may be required when monuments, occupation lines, legal descriptions, or existing conditions conflict.
What you may need
- Complete, legible survey showing the full parcel
- Surveyor seal, date, legal description, and boundary dimensions
- Recorded easements and visible improvements
- Updated field work when new construction or boundary uncertainty makes the old copy unreliable
- A separate site-plan layer showing the proposed project
Where to get it or verify it
- Check the purchase closing packet, title company file, lender file, or prior permit records.
- Hire a licensed land surveyor when no acceptable copy exists or existing conditions have changed.
- Ask the reviewing office whether it accepts an older survey, recorded plat, GIS base, or owner-drawn alternative for this project type.
Common mistakes that create comments or delays
- Calling an assessor map or aerial screenshot a survey
- Cropping out dimensions, notes, the seal, or part of the lot
- Using a survey that predates major structures without showing current conditions
- Assuming the survey itself shows the proposed project
What to do next
- Locate the best existing survey before ordering a new one.
- Confirm that it shows the full lot and current relevant conditions.
- Ask the AHJ what property base it accepts for this scope.
- Use the accepted base to prepare a coordinated site plan.