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📐 As-Built Documentation

As-built drawings document what was actually constructed. They're essential for closeout, future maintenance, and avoiding problems during renovations.

Key Principle

Mark up as you go. Trying to create as-builts from memory at the end of a project is impossible and inaccurate.

What Are As-Builts?​

As-built drawings show:

  • Actual locations of installed work
  • Deviations from original design
  • Hidden conditions
  • Final dimensions
  • Equipment locations
  • Routing of MEP systems

Why They Matter​

For the owner:

  • Maintenance and repairs
  • Future renovations
  • Space planning
  • Emergency response

For you:

  • Required for final payment
  • Reduces callback confusion
  • Demonstrates professionalism
  • Protects against future claims

As-Built Requirements​

Contract Requirements​

Review your contract for:

  • Who prepares as-builts
  • Format required (paper, CAD, BIM)
  • Level of detail expected
  • Submission timeline
  • Number of copies

Typical Requirements​

Project TypeTypical Requirement
ResidentialMarked-up plans, informal
CommercialFormal as-builts, CAD format
GovernmentFull as-built CAD or BIM
MEP HeavyDetailed routing and locations

Creating As-Builts​

Start at Project Beginning​

Set up your system:

  1. Designate as-built drawing set
  2. Keep in field office
  3. Assign responsibility for marking up
  4. Review weekly

What to Mark Up​

General:

  • All changes from drawings
  • Field-verified dimensions
  • Actual material used (if different)
  • Equipment model numbers/serial numbers

Structural:

  • Footing locations and depths
  • Actual pile locations
  • Embed locations
  • Structural modifications

Mechanical:

  • Duct routing and sizes
  • Equipment locations
  • Valve locations
  • Access panel locations

Electrical:

  • Conduit routing
  • Panel locations
  • Junction box locations
  • Circuit assignments

Plumbing:

  • Pipe routing and sizes
  • Valve locations
  • Cleanout locations
  • Fixture rough-in dimensions

Site:

  • Utility locations and depths
  • Storm/sanitary routing
  • Valve and manhole locations
  • Actual grades

How to Mark Up​

Use consistent notation:

  • Red ink for changes
  • Blue for clarifications
  • Green for added items
  • Clear dimensions
  • Legible notes

Include:

  • Date of change
  • Initials of person marking
  • Reference to RFI/ASI if applicable
  • Reason for change (brief)

Hidden Work Documentation​

Before It's Covered​

Document with:

  • As-built markup
  • Photographs
  • Measurements from reference points
  • GPS coordinates (for underground)

Critical Hidden Items​

Underground:

  • Utility depths and locations
  • Tie-in points
  • Valve locations
  • Sleeve locations

In Walls:

  • Blocking locations
  • Fire stopping
  • Sleeves and penetrations
  • Conduit and pipe routing

Above Ceilings:

  • Equipment locations
  • Access requirements
  • Routing of systems
  • Fire/smoke damper locations

Photo Documentation for As-Builts​

What to Photograph​

Before concealment:

  • Underground utilities
  • Slab rough-ins
  • Wall rough-ins
  • Above-ceiling work
  • Fire stopping

Include reference points:

  • Tape measure in photo
  • Reference to column lines or walls
  • Multiple angles
  • Wide and close-up shots

Organizing Photos​

File naming: [Date]-[Location]-[System]-[Description] Example: 2024-01-15-Level2-Plumbing-WasteRoughin.jpg

Create index: Link photos to drawing locations

Final As-Built Preparation​

Review Process​

Before finalizing:

  1. Gather all marked-up drawings
  2. Collect photos of hidden work
  3. Compile RFIs and ASIs
  4. Verify all changes captured
  5. Review with superintendent

Creating Final Documents​

If submitting marked-up drawings:

  • Clean, legible markups
  • Consistent notation
  • Complete coverage
  • Organized set

If CAD/BIM required:

  • Transfer all field markups
  • Verify accuracy
  • Include all changes
  • Follow format requirements

Coordination with Subs​

Collect from subs:

  • Their as-built markups
  • Equipment submittals with serial numbers
  • Specific routing information
  • Manufacturer warranties

Compile and verify:

  • All sub info included
  • Consistent format
  • No conflicts
  • Complete coverage

As-Built Checklist​

Site​

  • Utility locations and depths
  • Storm drainage routing
  • Sanitary sewer routing
  • Water service location
  • Gas service location
  • Electrical service routing
  • Site lighting locations
  • Paving extents
  • Final grades

Structure​

  • Foundation locations
  • Slab thickness and elevation
  • Structural modifications
  • Penetrations
  • Embeds and anchors

Architectural​

  • Wall locations (if varied)
  • Door swing directions
  • Ceiling heights
  • Access panels
  • Finished floor elevations

Mechanical​

  • Equipment locations
  • Duct routing
  • Diffuser/grille locations
  • Thermostat locations
  • Control valves
  • Access requirements

Electrical​

  • Panel locations
  • Conduit routing
  • Junction boxes
  • Device locations
  • Circuit directory
  • Emergency circuits

Plumbing​

  • Fixture locations
  • Pipe routing and sizes
  • Valve locations
  • Cleanout locations
  • Water heater location
  • Shut-off locations

Fire Protection​

  • Sprinkler head locations
  • Valve locations
  • FDC location
  • Control panel location

Common Mistakes​

1. Waiting Until the End​

Problem: Can't remember what changed Solution: Mark up weekly throughout project

2. Incomplete Information​

Problem: Missing critical changes Solution: Systematic review before concealment

3. Illegible Markups​

Problem: Can't read the information Solution: Use clear notation, neatly written

4. Missing Sub Input​

Problem: MEP routing not shown Solution: Require sub as-builts in subcontract

5. No Photo Documentation​

Problem: Can't prove hidden locations Solution: Photo documentation before covering

Digital As-Builts​

BIM As-Builts​

Benefits:

  • 3D visualization
  • Clash detection
  • Easier future use
  • Links to specifications

Requirements:

  • May require laser scanning
  • Model updates from field
  • Coordination with design team
  • Software compatibility

Scan to BIM​

Process:

  1. Laser scan completed work
  2. Compare to design model
  3. Update model to match reality
  4. Verify accuracy
  5. Deliver final model

Digital Markup Tools​

Options:

  • PDF markup apps
  • BIM field apps
  • Photo documentation apps
  • Integrated project management tools

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