Somebody tells you the project needs a survey. You ask which one, and the answer comes back with a shrug or a pair of terms you’ve half heard before: topographic, as-built. They sound similar and they’re often mixed up, but they answer opposite questions.
If you’re stuck on topographic vs as-built survey, the quickest way to sort it out is by timing. One looks at the site before anything is built. The other records what actually got built.
What’s the difference between a topographic and an as-built survey?
A topographic survey maps the land as it is now: the ground levels, the slopes, and the features sitting on it, like buildings, curbs, fences, trees and visible utilities. Designers use it to plan what comes next.
An as-built survey measures what has already been constructed and shows where it ended up. It’s used to confirm the work matches the approved plans, or to document where it doesn’t.
One is the starting point of a project. The other is the proof at the end.
Which one fits your situation
| Your situation | Likely survey |
|---|---|
| Designing a new house, addition or site plan and need to know the existing ground and features | Topographic |
| Planning grading or drainage on a sloped lot | Topographic |
| Buying vacant land and want to understand how it lies | Topographic |
| Construction is finished and the city or lender wants proof of where things were built | As-built |
| Checking that a foundation, structure or utility went in where the plans said | As-built |
| No reliable drawings of an existing building and you need to renovate | Usually as-built |
| Closing out a project and handing over records | As-built |
If your situation sits somewhere between two rows, that’s normal. Plenty of projects use both, one at the start and one at the end.
A simple way to remember it
Ask yourself one question: has the building been built yet?
- Not yet: you probably want a topographic survey.
- Already built: you probably want an as-built survey.
The exceptions are renovations, where an as-built of the existing structure often comes first, and large projects with stages, where you may need an as-built partway through.
What each one gives you
A topographic survey typically gives your designer ground elevations, the location of existing features, and the information needed to plan grading and drainage. You can read more about what we cover on our topographic survey page.
An as-built survey typically gives you a measured record of the finished work, positioned against the property and the approved plans. Details about that service are on our as-built survey page.
Where people go wrong
Ordering a topographic when they need an as-built. This happens when the building already exists and someone asks for a “site survey.” A topographic shows the ground and features but isn’t meant to verify construction against plans.
Ordering an as-built too late. If a city or lender needs it for closing out, leaving it to the last week puts the whole project on hold.
Assuming either one shows property lines. Neither is a boundary survey. If your question is where the lot line is, you need a different survey, and that’s a conversation worth having at the start.
Not sure? Describe the project
Most of the confusion goes away once the surveyor hears what you’re trying to do. Send us the address, what’s built or planned, and who’s asking for the survey (a city, a lender, an engineer), and we’ll tell you which one fits. Use our contact page or call 647-914-3361.