BIM Coordination Skill
Overview
The bim-coordination skill provides Building Information Modeling coordination and management capabilities for construction superintendents and field managers. This is not a skill about creating BIM models -- it is about using BIM models and their outputs to build better, faster, and with fewer conflicts in the field.
The construction superintendent's relationship with BIM has fundamentally changed. You are no longer handed a stack of 2D drawings and expected to figure out how everything fits together in three dimensions. Instead, you have access to coordinated 3D models that show exactly how structural, mechanical, electrical, plumbing, and architectural elements relate to each other in space and time.
Critical distinction: As a superintendent, you do not model. You USE models and their outputs. Your role is to:
- Verify that what is modeled matches what is built (and vice versa)
- Participate in clash detection workflows and drive field resolution
- Use 4D scheduling visualizations to plan and communicate sequencing
- Coordinate laser scanning and drone surveys for as-built documentation
- Ensure the digital twin handoff at closeout meets owner requirements
How BIM Changes the Super's Workflow
Traditional (2D Plan Sets):
- Overlay multiple sheets mentally to find conflicts
- Discover clashes during installation (expensive, schedule-killing)
- Rely on RFIs to resolve spatial conflicts after they are found in the field
- As-built documentation through redline markups on paper
BIM-Based Coordination:
- Clashes identified digitally before construction begins
- 3D visualization of complex intersections available on tablet in the field
- 4D scheduling ties model elements to activities for visual sequencing
- Laser scanning and drones provide precise as-built verification
- Digital twin handoff gives the owner a living model for facility management
This skill provides:
- BIM Execution Plan (BxP) superintendent responsibilities
- Clash detection workflows from identification through field resolution
- Model-to-field verification methods and tolerances
- 4D scheduling integration for phasing and logistics
- Laser scanning and point cloud management
- Drone survey planning and deliverable management
- Digital twin and closeout handoff requirements
- LOD specification guidance by discipline and phase
- Structured data model for all BIM coordination activities
- Integration with other ForemanOS skills
Key Principle: BIM coordination is not a design-phase activity that ends when construction starts. The model is a living document that must be continuously verified against field conditions, updated with as-built information, and handed off as a functional digital twin at project completion.
BIM Execution Plan (BxP) -- Superintendent Responsibilities
What a BxP Contains
The BIM Execution Plan (also called BxP or BEP) is the project-specific roadmap for how BIM will be used. It is typically produced by the BIM Manager or VDC Manager during preconstruction and covers:
- Project BIM goals and uses -- what BIM will be used for (coordination, scheduling, estimating, facility management)
- Model ownership matrix -- who creates and maintains each discipline model
- Model development schedule -- when models are due at each phase
- LOD requirements by element -- level of development expected at each milestone
- Software and platform standards -- Revit version, Navisworks version, file naming, exchange formats
- Coordination process -- meeting schedule, clash detection rules, resolution workflow
- Quality control procedures -- model audit checklists, validation rules
- Deliverable requirements -- what the owner receives at closeout
- File sharing and CDE (Common Data Environment) -- where models live, access permissions, version control
Superintendent's BxP Responsibilities
The super does not write the BxP but is responsible for key field-related elements:
Field Verification Protocol
- When and how field conditions are checked against the model
- Who performs verification (super, layout crew, survey team)
- What tolerances trigger a discrepancy report
- How deviations are documented and communicated back to the modeling team
Reality Capture Coordination
- Scheduling laser scans and drone flights
- Providing safe access for scanning crews
- Reviewing scan deliverables for completeness
- Coordinating scan timing with construction activities (scan before cover-up)
As-Built Model Updates
- Documenting field changes that differ from the coordinated model
- Red-lining model discrepancies for the BIM team to incorporate
- Verifying as-built model accuracy before closeout submission
BIM Coordination Meeting Participation
- Attending weekly (or biweekly) BIM coordination meetings
- Reporting field conditions that affect model accuracy
- Providing construction sequence input for 4D scheduling
- Identifying upcoming work areas that need clash resolution priority
Model Access -- Viewer Software
The superintendent needs read access to models but does not need full modeling software. Common viewer platforms:
| Platform |
Type |
Cost |
Key Features |
| Navisworks Freedom |
Desktop viewer |
Free |
View NWD files, basic navigation, saved viewpoints |
| Autodesk Docs / BIM 360 |
Cloud platform |
Included with project license |
Browser/mobile, markup, issues, model coordination |
| Procore BIM |
Cloud platform |
Included with Procore license |
Browser/mobile, linked to Procore workflows |
| Trimble Connect |
Cloud platform |
Free tier available |
Browser/mobile, field overlay, mixed reality |
| Dalux |
Cloud/mobile |
Subscription |
AR field overlay, BIM viewer, quality management |
Field tip: Download models for offline viewing before going to areas with poor connectivity. Autodesk Docs and Procore both support offline model caching on tablets.
Clash Detection Workflows
Types of Clashes
Clash detection identifies conflicts between building systems before they become costly field problems. There are three types:
1. Hard Clashes (Physical Intersection)
- Two elements occupy the same physical space
- Example: Ductwork passes through a structural beam
- Example: Conduit runs through a plumbing pipe
- These MUST be resolved before installation -- there is no field fix for two objects in the same space
2. Soft Clashes (Clearance Violation)
- Two elements do not physically intersect but violate required clearances
- Example: Ductwork is within 2" of a sprinkler head (needs 18" clearance for NFPA compliance)
- Example: Electrical panel has insufficient working clearance (NEC 110.26 requires 36" minimum)
- Example: Insulated pipe does not have enough space for insulation thickness
- Soft clash tolerances are defined per system and per code requirement
3. 4D Clashes (Time/Space Conflicts)
- Two activities require the same space at the same time based on the schedule
- Example: MEP rough-in scheduled in the same area where concrete is being poured
- Example: Crane swing radius conflicts with active work area during the same week
- 4D clashes require schedule adjustment, not model adjustment
Clash Detection Tools
| Tool |
Capability |
Typical User |
| Navisworks Manage |
Full clash detection with Clash Detective |
BIM/VDC Manager |
| BIM 360 Model Coordination |
Cloud-based automated clash detection |
BIM/VDC Manager, PM |
| Solibri |
Rule-based model checking and clash detection |
BIM Manager |
| Navisworks Simulate |
Limited clash detection |
Project Engineer |
| Trimble Connect |
Basic interference checking |
Field team |
Super's role: You typically do not run the clash detection software. Your role is to review clash reports, prioritize resolution based on construction sequence, drive field resolution, and verify that resolved clashes are actually resolved in the field.
Reading Clash Reports
A typical clash report from Navisworks Clash Detective contains:
- Clash ID: Unique identifier (e.g., CLH-MEP-STR-0042)
- Clash Type: Hard, soft (with tolerance), or 4D
- Status: New, Active, Reviewed, Resolved, Approved
- Elements Involved: Element 1 (discipline, type, size) vs. Element 2 (discipline, type, size)
- Grid Location: Column grid intersection (e.g., between grids C-D / 3-4)
- Level/Elevation: Floor and elevation of the clash
- Distance: For hard clashes, penetration depth; for soft clashes, clearance shortfall
- Viewpoint: Saved camera position showing the clash in the model
- Date Found: When the clash was first detected
- Assigned To: Trade or person responsible for resolution
Grouping and Filtering Clash Reports
Raw clash counts can be overwhelming (thousands of clashes in a complex project). Effective management requires:
- Group by Zone/Area -- Focus on areas coming up in the schedule first
- Group by Discipline Pair -- MEP/Structural, MEP/MEP, MEP/Architectural
- Filter Duplicates -- Same elements clashing at multiple points count as one issue
- Filter by Tolerance -- Ignore clashes below meaningful thresholds (e.g., <1/16" penetration)
- Prioritize by Schedule -- Areas with work starting in the next 2-4 weeks get priority
Superintendent's Role in Field Resolution
When a clash cannot be resolved through model adjustment alone, the super drives field resolution:
- RFI Generation -- When the clash reveals a design conflict, generate an RFI with the clash viewpoint attached
- On-Site Resolution -- When trades can resolve a routing conflict in the field within tolerances, document the agreed-upon solution
- Field Routing -- When the model shows the ideal path but field conditions require adjustment, direct the adjusted routing and document for as-built
Clash Resolution Meeting Format
Frequency: Weekly during active coordination phases, biweekly during less intensive periods
Agenda:
- Review new clashes since last meeting (5 min)
- Status update on previously assigned clashes (10 min)
- Walk through highest-priority clashes by area (20 min)
- Display clash viewpoint in model
- Identify responsible trades
- Discuss resolution options
- Assign resolution owner and deadline
- Review upcoming work areas needing pre-clash check (5 min)
- RFI status for design-related clashes (5 min)
- Action items and next meeting date (5 min)
Attendees: Superintendent, BIM/VDC Manager, MEP Coordinator, affected trade foremen, Project Engineer (for RFI tracking)
Common Clash Categories
MEP vs. Structural:
- Ductwork through beams or columns
- Piping through shear walls
- Conduit through post-tension tendons
- Hangers conflicting with structural connections
- Resolution: Typically requires structural engineer review; may need beam penetration sleeves, routing changes, or supplemental framing
MEP vs. MEP:
- Ductwork vs. piping (most common)
- Conduit vs. piping
- Cable tray vs. ductwork
- Fire sprinkler vs. everything else
- Resolution: Priority rules apply (gravity drain > pressure pipe > ductwork > conduit > cable tray); coordinate elevation stacking
MEP vs. Architectural:
- Ductwork in ceiling plenum exceeding ceiling height
- Piping conflicts with wall framing
- Equipment clearances vs. room dimensions
- Access panel locations vs. finish requirements
- Resolution: May require ceiling height adjustment, soffit additions, room dimension changes, or equipment relocation
Clash Resolution Documentation
Every resolved clash must be documented with:
- Clash ID and original clash report reference
- Resolution Description -- what was changed (routing, elevation, size, elimination)
- Resolution Type -- model change, field adjustment, design change (RFI), tolerance acceptance
- Responsible Party -- who made the change
- Verification -- confirmation that the resolution is reflected in the model or documented as field deviation
- Date Resolved and Date Verified
Clash Status Tracking
| Status |
Definition |
| New |
Clash detected, not yet reviewed |
| Active |
Reviewed, assigned to a responsible party for resolution |
| Reviewed |
Resolution proposed, awaiting approval |
| Resolved |
Resolution implemented in the model or documented as field deviation |
| Approved |
Resolution verified in the field and/or model -- closed |
Model-to-Field Verification
Tablet/Phone Overlay
Modern BIM workflows allow superintendents to overlay the 3D model on the physical job site using augmented reality (AR):
- Dalux BIM Viewer -- AR overlay on iOS/Android, point device at installed work to compare against model
- Trimble Connect AR -- Mixed reality overlay with Trimble hardware or mobile device
- OpenSpace -- 360-degree capture walks linked to model for progress verification
- HoloBuilder -- Job walk capture with BIM overlay comparison
Setup requirements: Calibrated device, known reference points (survey control), current model version loaded, adequate lighting for camera-based AR.
Accuracy considerations: Mobile AR is useful for gross conflict identification (is the duct in the right bay?) but not for precision measurement. Use total station or laser scanning for tolerance verification.
Layout from BIM Coordinates
BIM models contain precise coordinate data that can be exported directly to layout equipment:
- Total Station with BIM Export -- Export point coordinates from the model, import to total station, lay out points in the field
- Robotic Total Station (RTS) -- One-person layout using BIM coordinates with automated prism tracking
- Layout software -- Trimble Field Link, Topcon MAGNET, Leica iCON -- bridge between BIM and field layout hardware
Workflow:
- BIM coordinator exports layout points from the model (DXF, CSV, or native format)
- Survey/layout crew imports points to total station controller
- Points are laid out in the field with paint, tacks, or laser marks
- As-built points are captured and compared back to the model
- Deviations outside tolerance are flagged for resolution
Verification Tolerances by Trade and Element Type
| Trade/Element |
Typical Tolerance |
Reference |
| Structural steel columns |
+/- 1/4" plan, +/- 3/8" elevation |
AISC Code of Standard Practice |
| Cast-in-place concrete walls |
+/- 1/4" plan location |
ACI 117 |
| Cast-in-place concrete slabs |
+/- 3/4" elevation (FF/FL dependent) |
ACI 117 |
| MEP rough-in (horizontal) |
+/- 1/2" from model location |
Project-specific (check BxP) |
| MEP rough-in (elevation) |
+/- 1/4" from model elevation |
Project-specific (check BxP) |
| Fire sprinkler heads |
+/- 1" from ceiling grid |
NFPA 13 / reflected ceiling plan |
| Curtain wall anchors |
+/- 1/8" plan, +/- 1/4" elevation |
Manufacturer specs |
| Embedded items |
+/- 1/4" horizontal, +/- 1/2" vertical |
Project-specific |
| Electrical rough-in (boxes) |
+/- 1/2" plan, +/- 1/4" elevation |
NEC / project specs |
| Plumbing waste/vent |
+/- 1/4" for slope verification |
UPC / IPC (slope tolerance 1/8"/ft min) |
Critical note: Always check the project BxP and specifications for project-specific tolerances. The values above are industry-typical but your project may have tighter or looser requirements.
Field Discrepancy Reporting
When field conditions deviate from the model beyond tolerance, document using a model-to-field deviation log:
| Field |
Description |
| Deviation ID |
Unique identifier (e.g., DEV-2024-0015) |
| Date |
Date deviation discovered |
| Location |
Grid intersection, level, room/area |
| Element |
What was measured (e.g., "12" supply duct at grid C-4, Level 3") |
| Modeled Value |
What the model shows (position, elevation, size) |
| Field Value |
What was measured in the field |
| Deviation |
Difference (e.g., "6" south of modeled location") |
| Within Tolerance? |
Yes/No based on applicable tolerance standard |
| Impact |
Effect on other trades, schedule, function |
| Resolution |
Action required (move element, update model, RFI, accept as-is) |
| Status |
Open, In Progress, Resolved |
As-Built Model Updating Workflow
- Field Documentation -- Super documents as-built conditions (photos, measurements, redline sketches)
- Deviation Log Entry -- Discrepancy logged with all required fields
- BIM Team Notification -- Deviation log shared with BIM coordinator/modeler
- Model Update -- BIM team updates model to reflect as-built conditions
- Verification -- Super reviews updated model against field to confirm accuracy
- Closeout Integration -- As-built model becomes the basis for digital twin handoff
Extended reference: Detailed examples, templates, scoring rubrics, and best practices are in references/skill-detail.md.
1---2name: bim-coordination3description: BIM coordination and model-based field management for construction superintendents. Manage clash detection workflows, model-to-field verification, 4D scheduling integration, laser scanning and point cloud operations, drone surveys, digital twin closeout handoff, and LOD specification tracking. Track clash reports, model reviews, field verifications, scan records, drone flights, and coordination meetings through a structured data model. Integrates with morning-brief, daily-report, rfi-preparer, look-ahead-planner, closeout-commissioning, and drawing-control. Triggers: "BIM", "model", "clash", "clash detection", "Navisworks", "Revit", "coordination", "4D", "laser scan", "point cloud", "drone", "digital twin", "LOD", "BIM execution plan", "BxP", "model review".4---56# BIM Coordination Skill78## Overview910The **bim-coordination** skill provides Building Information Modeling coordination and management capabilities for construction superintendents and field managers. This is not a skill about creating BIM models -- it is about **using** BIM models and their outputs to build better, faster, and with fewer conflicts in the field.1112The construction superintendent's relationship with BIM has fundamentally changed. You are no longer handed a stack of 2D drawings and expected to figure out how everything fits together in three dimensions. Instead, you have access to coordinated 3D models that show exactly how structural, mechanical, electrical, plumbing, and architectural elements relate to each other in space and time.1314**Critical distinction**: As a superintendent, you do not model. You USE models and their outputs. Your role is to:15- Verify that what is modeled matches what is built (and vice versa)16- Participate in clash detection workflows and drive field resolution17- Use 4D scheduling visualizations to plan and communicate sequencing18- Coordinate laser scanning and drone surveys for as-built documentation19- Ensure the digital twin handoff at closeout meets owner requirements2021### How BIM Changes the Super's Workflow2223**Traditional (2D Plan Sets)**:24- Overlay multiple sheets mentally to find conflicts25- Discover clashes during installation (expensive, schedule-killing)26- Rely on RFIs to resolve spatial conflicts after they are found in the field27- As-built documentation through redline markups on paper2829**BIM-Based Coordination**:30- Clashes identified digitally before construction begins31- 3D visualization of complex intersections available on tablet in the field32- 4D scheduling ties model elements to activities for visual sequencing33- Laser scanning and drones provide precise as-built verification34- Digital twin handoff gives the owner a living model for facility management3536This skill provides:37- BIM Execution Plan (BxP) superintendent responsibilities38- Clash detection workflows from identification through field resolution39- Model-to-field verification methods and tolerances40- 4D scheduling integration for phasing and logistics41- Laser scanning and point cloud management42- Drone survey planning and deliverable management43- Digital twin and closeout handoff requirements44- LOD specification guidance by discipline and phase45- Structured data model for all BIM coordination activities46- Integration with other ForemanOS skills4748**Key Principle**: BIM coordination is not a design-phase activity that ends when construction starts. The model is a living document that must be continuously verified against field conditions, updated with as-built information, and handed off as a functional digital twin at project completion.4950---5152## BIM Execution Plan (BxP) -- Superintendent Responsibilities5354### What a BxP Contains5556The BIM Execution Plan (also called BxP or BEP) is the project-specific roadmap for how BIM will be used. It is typically produced by the BIM Manager or VDC Manager during preconstruction and covers:5758- **Project BIM goals and uses** -- what BIM will be used for (coordination, scheduling, estimating, facility management)59- **Model ownership matrix** -- who creates and maintains each discipline model60- **Model development schedule** -- when models are due at each phase61- **LOD requirements by element** -- level of development expected at each milestone62- **Software and platform standards** -- Revit version, Navisworks version, file naming, exchange formats63- **Coordination process** -- meeting schedule, clash detection rules, resolution workflow64- **Quality control procedures** -- model audit checklists, validation rules65- **Deliverable requirements** -- what the owner receives at closeout66- **File sharing and CDE (Common Data Environment)** -- where models live, access permissions, version control6768### Superintendent's BxP Responsibilities6970The super does not write the BxP but is responsible for key field-related elements:71721. **Field Verification Protocol**73 - When and how field conditions are checked against the model74 - Who performs verification (super, layout crew, survey team)75 - What tolerances trigger a discrepancy report76 - How deviations are documented and communicated back to the modeling team77782. **Reality Capture Coordination**79 - Scheduling laser scans and drone flights80 - Providing safe access for scanning crews81 - Reviewing scan deliverables for completeness82 - Coordinating scan timing with construction activities (scan before cover-up)83843. **As-Built Model Updates**85 - Documenting field changes that differ from the coordinated model86 - Red-lining model discrepancies for the BIM team to incorporate87 - Verifying as-built model accuracy before closeout submission88894. **BIM Coordination Meeting Participation**90 - Attending weekly (or biweekly) BIM coordination meetings91 - Reporting field conditions that affect model accuracy92 - Providing construction sequence input for 4D scheduling93 - Identifying upcoming work areas that need clash resolution priority9495### Model Access -- Viewer Software9697The superintendent needs read access to models but does not need full modeling software. Common viewer platforms:9899| Platform | Type | Cost | Key Features |100|---|---|---|---|101| Navisworks Freedom | Desktop viewer | Free | View NWD files, basic navigation, saved viewpoints |102| Autodesk Docs / BIM 360 | Cloud platform | Included with project license | Browser/mobile, markup, issues, model coordination |103| Procore BIM | Cloud platform | Included with Procore license | Browser/mobile, linked to Procore workflows |104| Trimble Connect | Cloud platform | Free tier available | Browser/mobile, field overlay, mixed reality |105| Dalux | Cloud/mobile | Subscription | AR field overlay, BIM viewer, quality management |106107**Field tip**: Download models for offline viewing before going to areas with poor connectivity. Autodesk Docs and Procore both support offline model caching on tablets.108109---110111## Clash Detection Workflows112113### Types of Clashes114115Clash detection identifies conflicts between building systems before they become costly field problems. There are three types:116117**1. Hard Clashes (Physical Intersection)**118- Two elements occupy the same physical space119- Example: Ductwork passes through a structural beam120- Example: Conduit runs through a plumbing pipe121- These MUST be resolved before installation -- there is no field fix for two objects in the same space122123**2. Soft Clashes (Clearance Violation)**124- Two elements do not physically intersect but violate required clearances125- Example: Ductwork is within 2" of a sprinkler head (needs 18" clearance for NFPA compliance)126- Example: Electrical panel has insufficient working clearance (NEC 110.26 requires 36" minimum)127- Example: Insulated pipe does not have enough space for insulation thickness128- Soft clash tolerances are defined per system and per code requirement129130**3. 4D Clashes (Time/Space Conflicts)**131- Two activities require the same space at the same time based on the schedule132- Example: MEP rough-in scheduled in the same area where concrete is being poured133- Example: Crane swing radius conflicts with active work area during the same week134- 4D clashes require schedule adjustment, not model adjustment135136### Clash Detection Tools137138| Tool | Capability | Typical User |139|---|---|---|140| Navisworks Manage | Full clash detection with Clash Detective | BIM/VDC Manager |141| BIM 360 Model Coordination | Cloud-based automated clash detection | BIM/VDC Manager, PM |142| Solibri | Rule-based model checking and clash detection | BIM Manager |143| Navisworks Simulate | Limited clash detection | Project Engineer |144| Trimble Connect | Basic interference checking | Field team |145146**Super's role**: You typically do not run the clash detection software. Your role is to review clash reports, prioritize resolution based on construction sequence, drive field resolution, and verify that resolved clashes are actually resolved in the field.147148### Reading Clash Reports149150A typical clash report from Navisworks Clash Detective contains:151152- **Clash ID**: Unique identifier (e.g., CLH-MEP-STR-0042)153- **Clash Type**: Hard, soft (with tolerance), or 4D154- **Status**: New, Active, Reviewed, Resolved, Approved155- **Elements Involved**: Element 1 (discipline, type, size) vs. Element 2 (discipline, type, size)156- **Grid Location**: Column grid intersection (e.g., between grids C-D / 3-4)157- **Level/Elevation**: Floor and elevation of the clash158- **Distance**: For hard clashes, penetration depth; for soft clashes, clearance shortfall159- **Viewpoint**: Saved camera position showing the clash in the model160- **Date Found**: When the clash was first detected161- **Assigned To**: Trade or person responsible for resolution162163### Grouping and Filtering Clash Reports164165Raw clash counts can be overwhelming (thousands of clashes in a complex project). Effective management requires:1661671. **Group by Zone/Area** -- Focus on areas coming up in the schedule first1682. **Group by Discipline Pair** -- MEP/Structural, MEP/MEP, MEP/Architectural1693. **Filter Duplicates** -- Same elements clashing at multiple points count as one issue1704. **Filter by Tolerance** -- Ignore clashes below meaningful thresholds (e.g., <1/16" penetration)1715. **Prioritize by Schedule** -- Areas with work starting in the next 2-4 weeks get priority172173### Superintendent's Role in Field Resolution174175When a clash cannot be resolved through model adjustment alone, the super drives field resolution:1761771. **RFI Generation** -- When the clash reveals a design conflict, generate an RFI with the clash viewpoint attached1782. **On-Site Resolution** -- When trades can resolve a routing conflict in the field within tolerances, document the agreed-upon solution1793. **Field Routing** -- When the model shows the ideal path but field conditions require adjustment, direct the adjusted routing and document for as-built180181### Clash Resolution Meeting Format182183**Frequency**: Weekly during active coordination phases, biweekly during less intensive periods184185**Agenda**:1861. Review new clashes since last meeting (5 min)1872. Status update on previously assigned clashes (10 min)1883. Walk through highest-priority clashes by area (20 min)189 - Display clash viewpoint in model190 - Identify responsible trades191 - Discuss resolution options192 - Assign resolution owner and deadline1934. Review upcoming work areas needing pre-clash check (5 min)1945. RFI status for design-related clashes (5 min)1956. Action items and next meeting date (5 min)196197**Attendees**: Superintendent, BIM/VDC Manager, MEP Coordinator, affected trade foremen, Project Engineer (for RFI tracking)198199### Common Clash Categories200201**MEP vs. Structural**:202- Ductwork through beams or columns203- Piping through shear walls204- Conduit through post-tension tendons205- Hangers conflicting with structural connections206- Resolution: Typically requires structural engineer review; may need beam penetration sleeves, routing changes, or supplemental framing207208**MEP vs. MEP**:209- Ductwork vs. piping (most common)210- Conduit vs. piping211- Cable tray vs. ductwork212- Fire sprinkler vs. everything else213- Resolution: Priority rules apply (gravity drain > pressure pipe > ductwork > conduit > cable tray); coordinate elevation stacking214215**MEP vs. Architectural**:216- Ductwork in ceiling plenum exceeding ceiling height217- Piping conflicts with wall framing218- Equipment clearances vs. room dimensions219- Access panel locations vs. finish requirements220- Resolution: May require ceiling height adjustment, soffit additions, room dimension changes, or equipment relocation221222### Clash Resolution Documentation223224Every resolved clash must be documented with:225- **Clash ID** and original clash report reference226- **Resolution Description** -- what was changed (routing, elevation, size, elimination)227- **Resolution Type** -- model change, field adjustment, design change (RFI), tolerance acceptance228- **Responsible Party** -- who made the change229- **Verification** -- confirmation that the resolution is reflected in the model or documented as field deviation230- **Date Resolved** and **Date Verified**231232### Clash Status Tracking233234| Status | Definition |235|---|---|236| **New** | Clash detected, not yet reviewed |237| **Active** | Reviewed, assigned to a responsible party for resolution |238| **Reviewed** | Resolution proposed, awaiting approval |239| **Resolved** | Resolution implemented in the model or documented as field deviation |240| **Approved** | Resolution verified in the field and/or model -- closed |241242---243244## Model-to-Field Verification245246### Tablet/Phone Overlay247248Modern BIM workflows allow superintendents to overlay the 3D model on the physical job site using augmented reality (AR):249250- **Dalux BIM Viewer** -- AR overlay on iOS/Android, point device at installed work to compare against model251- **Trimble Connect AR** -- Mixed reality overlay with Trimble hardware or mobile device252- **OpenSpace** -- 360-degree capture walks linked to model for progress verification253- **HoloBuilder** -- Job walk capture with BIM overlay comparison254255**Setup requirements**: Calibrated device, known reference points (survey control), current model version loaded, adequate lighting for camera-based AR.256257**Accuracy considerations**: Mobile AR is useful for gross conflict identification (is the duct in the right bay?) but not for precision measurement. Use total station or laser scanning for tolerance verification.258259### Layout from BIM Coordinates260261BIM models contain precise coordinate data that can be exported directly to layout equipment:2622631. **Total Station with BIM Export** -- Export point coordinates from the model, import to total station, lay out points in the field2642. **Robotic Total Station (RTS)** -- One-person layout using BIM coordinates with automated prism tracking2653. **Layout software** -- Trimble Field Link, Topcon MAGNET, Leica iCON -- bridge between BIM and field layout hardware266267**Workflow**:2681. BIM coordinator exports layout points from the model (DXF, CSV, or native format)2692. Survey/layout crew imports points to total station controller2703. Points are laid out in the field with paint, tacks, or laser marks2714. As-built points are captured and compared back to the model2725. Deviations outside tolerance are flagged for resolution273274### Verification Tolerances by Trade and Element Type275276| Trade/Element | Typical Tolerance | Reference |277|---|---|---|278| Structural steel columns | +/- 1/4" plan, +/- 3/8" elevation | AISC Code of Standard Practice |279| Cast-in-place concrete walls | +/- 1/4" plan location | ACI 117 |280| Cast-in-place concrete slabs | +/- 3/4" elevation (FF/FL dependent) | ACI 117 |281| MEP rough-in (horizontal) | +/- 1/2" from model location | Project-specific (check BxP) |282| MEP rough-in (elevation) | +/- 1/4" from model elevation | Project-specific (check BxP) |283| Fire sprinkler heads | +/- 1" from ceiling grid | NFPA 13 / reflected ceiling plan |284| Curtain wall anchors | +/- 1/8" plan, +/- 1/4" elevation | Manufacturer specs |285| Embedded items | +/- 1/4" horizontal, +/- 1/2" vertical | Project-specific |286| Electrical rough-in (boxes) | +/- 1/2" plan, +/- 1/4" elevation | NEC / project specs |287| Plumbing waste/vent | +/- 1/4" for slope verification | UPC / IPC (slope tolerance 1/8"/ft min) |288289**Critical note**: Always check the project BxP and specifications for project-specific tolerances. The values above are industry-typical but your project may have tighter or looser requirements.290291### Field Discrepancy Reporting292293When field conditions deviate from the model beyond tolerance, document using a model-to-field deviation log:294295| Field | Description |296|---|---|297| Deviation ID | Unique identifier (e.g., DEV-2024-0015) |298| Date | Date deviation discovered |299| Location | Grid intersection, level, room/area |300| Element | What was measured (e.g., "12" supply duct at grid C-4, Level 3") |301| Modeled Value | What the model shows (position, elevation, size) |302| Field Value | What was measured in the field |303| Deviation | Difference (e.g., "6" south of modeled location") |304| Within Tolerance? | Yes/No based on applicable tolerance standard |305| Impact | Effect on other trades, schedule, function |306| Resolution | Action required (move element, update model, RFI, accept as-is) |307| Status | Open, In Progress, Resolved |308309### As-Built Model Updating Workflow3103111. **Field Documentation** -- Super documents as-built conditions (photos, measurements, redline sketches)3122. **Deviation Log Entry** -- Discrepancy logged with all required fields3133. **BIM Team Notification** -- Deviation log shared with BIM coordinator/modeler3144. **Model Update** -- BIM team updates model to reflect as-built conditions3155. **Verification** -- Super reviews updated model against field to confirm accuracy3166. **Closeout Integration** -- As-built model becomes the basis for digital twin handoff317318---319320321---322323> **Extended reference**: Detailed examples, templates, scoring rubrics, and best practices are in `references/skill-detail.md`.