Module 19: Multidisciplinary Coordination, Clash Detection, and QA/QC

Use three deliberately separate review passes:

1. PASS 1 — SHEET QA: Is each sheet technically legible, complete, correctly identified, plotted, and current?
2. PASS 2 — DISCIPLINE CONSISTENCY: Do the plans, elevations, sections, details, schedules, risers, and calculations/notes within one discipline agree?
3. PASS 3 — MULTIDISCIPLINARY COORDINATION: Do different disciplines describe one physically compatible building/site condition?

Do not collapse the three passes into one visual scan. Each asks a different class of question and catches different failure modes.

Check every sheet as an independent deliverable:

• correct title and discipline;
• correct sheet number and index relationship;
• stated scale and appropriate scale usage;
• north arrow where orientation is needed;
• dimensions needed to define the work;
• levels/elevations/datums where needed;
• notes that are current, legible, and non-contradictory;
• symbols and abbreviations that match the legend;
• lineweights, linetypes, hatching, and hierarchy that remain readable when plotted;
• references to sections, details, elevations, schedules, and other sheets;
• drawing completeness within the sheet's intended scope;
• spelling, naming, room numbers, grid labels, tags, and terminology;
• plotting/cropping/page size and absence of hidden or clipped information;
• revision identity, date/status as required by the project's document-control system;
• no obsolete clouds, comments, markups, or superseded information accidentally left active.

A sheet can pass Pass 1 and still fail Pass 2 or Pass 3.

Pass 2 tests whether one discipline contradicts itself. Typical comparisons include:

A change made in one view is not complete until all dependent representations are updated.

Review the following interfaces explicitly rather than assuming that a general overlay covers them:

For complex work, break Pass 3 into discipline-pair sessions so that issues have clear owners.

Use realistic cases to train diagnosis:

The correct resolution depends on design intent, code, equipment, levels, cost, sequence, and professional judgment. The table identifies the conflict, not the answer.

Use issue category before assigning any project-specific priority. The category indicates whether the item can be corrected editorially or must return to the responsible discipline:

A project may add its own priority labels, response times, or risk ranking, but those controls must not obscure the category or the authority required to resolve it.

Do not invent a universal severity scale. Define one for the project and use it consistently. A defensible severity scheme usually considers:

• safety or code impact;
• structural or system-performance impact;
• construction impossibility;
• probability of rework or delay;
• cost/schedule exposure;
• number of disciplines/documents affected;
• whether the issue blocks permit, procurement, fabrication, installation, inspection, or commissioning;
• whether the issue can be corrected as drafting only or requires professional redesign.

A visually small clash can be critical if it affects structural integrity, fire safety, or a gravity connection.

At minimum, capture:

Avoid issue descriptions such as “fix clash.” State the exact condition, location, and conflicting requirements.

Coordination methods differ in capability, not purpose:

• Manual/light-table or printed overlay: useful for disciplined sheet-to-sheet comparison when drawings share scale/origin and the reviewer marks issues systematically.
• PDF overlay: improves transparency, revision comparison, and markup traceability; verify scale, page alignment, crop/origin, and revision before trusting the overlay.
• 2D CAD/reference overlay: useful for precise geometry comparison when coordinate systems and references are controlled.
• Federated BIM/model review: combines discipline models without pretending they are one author's design; model origins, levels, coordinates, element status, tolerances, and model version must be controlled.
• Automated clash detection: finds geometry/proximity conditions according to configured rules; the rule set, tolerances, exclusions, model completeness, and false-positive strategy must be documented.

No method eliminates the need for human review of constructibility, access, sequence, levels, fire-rating continuity, system function, or professional responsibility.

A clash test without a declared tolerance can generate noise or miss risk. Before running automated checks, define:

• which model categories are included;
• hard-clash versus clearance/proximity rules;
• project units and tolerance;
• whether insulation, finishes, hangers, access zones, and temporary/construction items are modeled;
• exclusions for intentional contacts or known accepted relationships;
• model status and level of information appropriate to the review stage;
• how duplicates and repeated instances are grouped;
• who reviews false positives and who owns true issues;
• whether any schedule-linked or 4D review is actually supported by current activity/sequence data rather than being inferred from model geometry.

Do not tune tolerances merely to make the clash count look smaller. A hard-clash test, a clearance test, and a schedule/sequence conflict are different checks and should not be reported as though one rule detects all three.

For the course project, Module 19 is the formal coordination gate before the final drawing package. The learner should run Pass 1 on every sheet, Pass 2 within each discipline, then Pass 3 across the complete two-storey building. The Coordination Issue Register should carry representative issues—such as a beam/duct clash, missing stair opening, ceiling-device conflict, undersized shaft, and incompatible site drainage connection—from discovery through approved decision, revision, verification, and closure.

A federation reports no geometric clashes, but one discipline model is an older revision. First verify the input register: author, revision, date, status, coordinate basis, and included scope for every information container.

Replace stale inputs through the controlled exchange process, rerun the affected checks, and record exclusions or unmodelled interfaces. Review access, function, levels, and document consistency in addition to object intersections. Close only the checks supported by the current, complete input set. A zero-clash count from mismatched revisions is a statement about that particular federation, not evidence that the current drawing package is coordinated.

• ISO 19650-1:2018 — Information management using building information modelling, Part 1: Concepts and principles — ISO; current published edition confirmed in 2024 at the 2026 review date.
• ISO 19650-2:2018 — Information management using building information modelling, Part 2: Delivery phase of the assets — ISO; current published edition at the 2026 review date while revision work is under development.
• ISO — Building Information Modelling standards overview — ISO lifecycle information-management context.
• Presidential Decree No. 1096 — National Building Code of the Philippines — Supreme Court E-Library.
• RA 9514 Revised Implementing Rules and Regulations, Revised 2019 — Bureau of Fire Protection; fire-safety coordination context.