Creating an As-Built Document: What Inspectors Actually Need

An as-built document (also called record drawings, as-constructed drawings, or field records) is a formal record of what was actually built — as opposed to what was designed. Inspectors use as-builts to verify that the installed work meets design intent, complies with code, and provides a permanent record for future utility locates and facility maintenance.

Most contractors produce as-builts that are either missing critical data, formatted inconsistently, or submitted too late. This guide explains exactly what inspectors require and how to build that documentation during construction instead of scrambling at the end.

Why As-Builts Matter (And Why Most Are Wrong)

A good as-built protects the contractor as much as it serves the inspector. When a property owner calls three years later claiming your sewer pipe is causing their basement to flood, your as-built is your defense. It shows: here is where the pipe is, here is what grade it was installed at, here is who verified it, and here is when the inspection was passed.

Most as-builts fail for one of three reasons:

• Missing data: The inspector requires invert elevations, actual grade, and deviation from design — but the as-built only shows “installed per plans.”
• No benchmark reference: Elevations are listed without stating what datum or benchmark they were measured from. The numbers are meaningless without a reference.
• Unverified data: The as-built was created from the design drawings, not from actual field measurements. Inspectors often ask: “Is this what you designed or what you built?”

What DOT Inspectors Require

Department of Transportation projects have the most rigorous as-built requirements. DOT inspectors typically require:

• Survey control information: Benchmark identifier, location description, and datum (NAVD88 most common in the US). Every elevation in the as-built traces back to a specific, documented benchmark.
• Equipment used for measurements: Instrument type, model, serial number, and calibration certificate date. If the instrument was not calibrated within the required period, the measurements may be rejected.
• Design vs. as-built comparison: A table showing design elevation and measured elevation at each control point. Deviation column is required — not optional.
• Pass/fail determination: Each measurement must be evaluated against the project tolerance. DOT typically allows ±0.05 ft (5/8 inch) for grade work and ±0.10 ft for utility installations.
• Crew and inspector sign-off: Date, crew foreman name, inspector name, and both signatures. Unsigned as-builts are not accepted.

What Sewer As-Builts Must Include

Municipal utility inspectors have specific requirements for sewer as-built documentation. For each manhole-to-manhole pipe run, the as-built must include:

Use the Invert Elevation Calculator to verify that your measured invert elevations produce the correct installed grade before submitting your as-built.

What Grade Work As-Builts Must Include

For site grading projects (parking lots, subgrade, athletic fields), as-built surveys document finished elevation at a grid or at specific control points. Requirements typically include:

• Grid spacing: DOT requires as-built elevations at 25–50 ft grid for road subgrade. Site projects typically require 25–50 ft grid for flatwork and 50–100 ft for rough grading.
• Design elevation at each grid point: From the grading plan; interpolated at the grid point location.
• Measured elevation at each grid point: From field survey with automatic or digital level.
• Deviation (measured − design): Positive deviation = high; negative deviation = low. Tolerance is typically ±0.05 ft for finish grade and ±0.10 ft for subgrade.
• Drainage direction verification: A note or arrow on the as-built confirming drainage flows to the designed low point (catch basin, swale, curb inlet).

Format: What Inspectors Actually Read

Inspectors review dozens of as-builts per year. They appreciate documents that get to the point. The most useful as-built format:

1. Cover page: Project name, owner, contractor, date, permit number, and inspector name. One page.
2. Control information: Benchmark description, datum, equipment used, calibration date. One page or section header.
3. Summary table: All measurement points in a table: design vs. as-built vs. deviation vs. pass/fail. The inspector reads this table first — it should be on page 2.
4. Deviation flag: Any measurement outside tolerance should be highlighted in red. Do not hide failures — inspectors find them anyway, and hiding them creates trust problems that follow your company for years.
5. Supporting data: Field notes, shot logs, and instrument calibration certificate in an appendix. Inspectors rarely read the appendix unless there's a dispute, but it must be present.
6. Sign-off page: Contractor representative and inspector signature lines with date.

Generating As-Builts in Sitemark

Sitemark generates inspector-ready as-built PDFs directly from your field shots. Here's the workflow:

1. Set up the job: Create a job in Sitemark with design elevations, benchmark information, and equipment assignments. Add the pipe run or grade grid before going to the field.
2. Log shots in real time: As you take field measurements, enter them in the Sitemark app. The app calculates deviation and pass/fail automatically. If a shot fails, you know immediately — before backfill, before paving.
3. Review the shot log: At the end of the job, review the complete shot log. Flag any failures and document corrective action (re-survey, adjust grade, re-test).
4. Generate the PDF: One button generates a formatted as-built PDF with: cover page, benchmark info, equipment details, complete data table with deviations, elevation profile chart for pipe runs, and signature block. No Excel, no reformatting.
5. Submit electronically or print: Email the PDF directly from Sitemark to the inspector or upload to the project portal. Or print and sign for projects requiring wet signatures.

Common As-Built Submission Errors

• Using design drawings as as-builts: Submitting a design drawing stamped “as-built” without field verification is fraud on DOT projects and grounds for contract termination. Always survey.
• Missing benchmark reference: Elevations without a benchmark reference are unverifiable. Always state the benchmark used, its published elevation, and the datum.
• Wrong instrument calibration date: Calibration certificates more than 12 months old (or whatever the project spec requires) are not accepted. Track calibration dates in Sitemark to avoid last-minute surprises.
• Submitting after concrete is placed: For utility as-builts, submit before final backfill or paving whenever possible. Post-paving corrections require jackhammering.
• Unresolved failures: Never submit an as-built with unresolved tolerance failures. Re-work the area, take passing measurements, and document the corrective action in the as-built.

Quick Reference: As-Built Tolerances by Project Type