What is the difference between as-built drawings and record drawings?

As-Built Drawings vs Record Drawings: A Complete Explanation

These two terms are frequently confused in the AEC industry, but they refer to fundamentally different types of documentation with different purposes, creation methods, and reliability levels.

What Are As-Built Drawings?

As-built drawings document the actual, existing conditions of a building or structure as it stands today. They are created through field verification — someone physically measures and documents what is really there.

Key characteristics of as-built drawings:

• Created by: A surveyor, 3D scanning technician, or field engineer
• Method: 3D laser scanning (1-6mm accuracy), total station measurement, or manual tape measurement
• Timing: Can be created at any point — for brand-new buildings or structures that are decades old
• Content: Verified dimensions, locations, and conditions based on direct measurement
• Accuracy: With 3D laser scanning, as-built drawings achieve ±1-6mm accuracy — far exceeding what is possible with traditional manual measurement

As-built drawings are considered the gold standard for documenting existing conditions because they are based on verified field data, not assumptions or markups.

What Are Record Drawings?

Record drawings are the final revised set of construction documents that the contractor updates during and after construction to reflect changes from the original design. They are sometimes called "as-builts" colloquially, but this is technically incorrect.

Key characteristics of record drawings:

• Created by: The general contractor maintains redline markups; the architect incorporates them into final documents
• Method: Redline markup of the original design drawings (adding notes, crossing out changes, sketching modifications)
• Timing: Created only during new construction — they document changes from the original design
• Content: Modifications to the design intent — moved walls, rerouted pipes, changed dimensions
• Accuracy: Highly variable — depends entirely on how diligent the contractor was in tracking changes

Why the Distinction Matters

The critical difference is verification vs. documentation of intent:

• As-built drawings answer: "What is actually there right now?"
• Record drawings answer: "What changed from the original design during construction?"

Studies consistently show that record drawings miss 30-40% of field changes, especially hidden elements like MEP routing behind walls, above-ceiling modifications, and underground utility adjustments. Contractors are busy building — not documenting — and many field changes go unrecorded.

Legal Standing

As-built drawings created through professional field verification (especially 3D laser scanning) carry significant legal weight because they represent independently verified conditions. They are routinely used in:

• Insurance claims (documenting pre-loss conditions)
• Legal disputes (proving actual dimensions and conditions)
• Permit applications (demonstrating existing conditions for renovation permits)
• Property transactions (due diligence documentation)

Record drawings, while important for contract closeout, are considered less authoritative because they depend on the contractor's diligence and are not independently verified.

When You Need Both

For new construction, both are typically required:

1. Record drawings at project closeout — documenting what changed during construction
2. As-built drawings for ongoing facility management — verified documentation that remains accurate even after subsequent modifications

For existing buildings, as-built drawings are essential because:

• Original record drawings may be decades old
• The building has likely been modified multiple times
• Previous renovation documentation may be incomplete or missing
• Current conditions are the only relevant data for renovation planning

How 3D Scanning Transforms As-Built Documentation

Modern 3D laser scanning has revolutionized as-built documentation by capturing millions of measurements in minutes rather than hours. A scanner like the Trimble X12 captures 2.2 million points per second with ±1mm accuracy, creating a comprehensive digital record of every visible surface.

This means as-built drawings created from 3D scan data are:

• More complete — every visible surface is captured, eliminating missed measurements
• More accurate — ±1-6mm vs ±0.5-1 inch for manual measurement
• Reusable — the point cloud can be re-measured remotely without returning to the site
• BIM-conversion-ready — scan data can be used by BIM modeling firms to create Revit models

For a deeper comparison, see our As-Built Drawings vs Record Drawings comparison page.

THE FUTURE 3D specializes in creating accurate as-built documentation using 3D laser scanning technology. Request a quote for your as-built documentation project.