When should MEP coordination start on a project?

Before procurement and before installation begins, ideally as shop drawing preparation starts, because resolving a clash on paper costs less than fixing it after the work is built.

Can all clashes be found before installation?

That cannot be guaranteed. Coordination and checking reveal what the drawings and models contain; problems that are not in the data or that relate to site conditions can still appear, which is why site inspection and dimension checks are needed.

Does clash detection require BIM?

No. Clashes can be reviewed on 2D drawings, while BIM models allow broader automated checks where they are available and permitted under the project contract.

Who is responsible for resolving clashes between HVAC, fire protection and electrical?

The contract sets it. The contractor usually coordinates its own systems, and the consultant reviews solutions that affect design or code compliance. The coordination lead and the approval route should be agreed before installation begins.

Can routes be changed after drawings are approved?

Yes, through a documented change procedure that reviews the impact on other disciplines, obtains approval from the relevant party, issues updated drawings and withdraws the old revision from site.

Which documents should be reviewed before installation starts?

The latest approved drawings, specifications, equipment schedules, the clash log and open queries, material approvals, and coordination meeting minutes.

How do shop drawings affect project cost and schedule?

Early review reduces the likelihood of rework and late changes, but it takes time during preparation. The real effect differs from project to project and cannot be estimated without studying the project documents.

MEP Coordination & Shop Drawings | Van Tech Egypt

Part of the suspended ceiling is finished, and then the HVAC duct turns out to cross the fire protection main or the cable route. Suddenly the job means dismantling, reinstalling, extra labour hours and a possible delay to handover. The problem is not a pipe in the wrong place; it is a clash that was never resolved before it reached site.

This article covers MEP coordination, the role of shop drawings and clash detection in preventing that problem. It is written for project owners, consultants, project managers, construction managers and technical offices. It looks at why clashes happen and what they cost, the difference between drawing types, a recommended coordination method, and how to assess a contractor's ability to coordinate, then explains where Van Tech fits in.

Key Takeaways

A clash found on site costs more than one resolved on paper, because it brings dismantling, remanufacture and knock-on effects on other trades and finishes.
Tender drawings are not ready for installation; shop drawings and coordinated drawings fix the routes, levels and openings.
Clash detection can be run on 2D drawings or BIM models, and it does not replace engineering review or site verification.
Drawing approval does not end coordination responsibility; that stays with the contract, and later changes need managing and updating.
Ask the contractor for a clash log, an RFI template and revision control procedures, not just a promise to coordinate.

1How Do MEP Clashes Turn into Cost and Delay?

The cost of a clash builds up because its effects do not stop at the trade where it appears. Changing a duct changes its supports and levels, may touch the neighbouring sprinkler line or cable tray, and delays ceiling closure and finishing.

Rework and Dismantling Costs

Remanufacturing ducts or modifying pipe and cable supports.
Labour, equipment and material already installed and then altered.
The effect of rework on other trades and the sequence of activities.

Effect on Finishes and Handover

Opening suspended ceilings or redoing some finishing work.
Delayed testing, or ceilings left open until concealed work is complete.
The effect of late changes on the programme and on coordination between contractors.

Direct and Indirect Costs

Direct: materials, labour and remanufacture.
Indirect: idle crews, rescheduling and delayed access to areas.

The causes and cost of a clash should be documented, rather than assuming that every delay comes from coordination alone.

2What Causes Clashes Between HVAC, Fire Protection and Electrical Systems?

HVAC, electrical and fire protection share the same space above ceilings, in shafts and in service rooms. Each drawing can be sound on its own and still create a problem once installed alongside the others.

Adjacent HVAC ducts, fire protection pipes and cable trays above a suspended ceiling before closure — Crowded service routes above a suspended ceiling before closure.

HVAC Routes vs. Fire Fighting Systems

Ducts crossing sprinkler pipes or fire mains.
The effect of ceiling heights and available levels on routing.
Maintaining sprinkler distribution requirements, including not obstructing sprinkler discharge under NFPA 13 and the approved design, and keeping valve access.

Ducts and Pipes vs. Cables and Their Supports

Crowded routes in ceiling voids, service rooms and shafts.
Access and maintenance space and the cable bends required.
Reviewing separation and clearances according to system type and the approved specification.

Level and Space Errors

Different vertical datums between discipline drawings.
Omitting insulation thickness, supports and maintenance space when calculating available height.
Missing coordination of slab openings, sleeves and builders' work.

Lack of Coordination Between Disciplines

Separate drawings issued without joint review.
Design changes that did not reach every drawing.
Technical queries left open when installation begins.

3Tender Drawings vs. Shop Drawings vs. Coordination Drawings

These types are often confused, which is one reason approved drawings get treated as ready for installation. The table shows the main differences; details vary with each project's contract.

Drawing type	Purpose	Level of detail	Usually prepared by
Tender Drawings	Show the proposed design, project scope and pricing basis	Varies by project; not necessarily sufficient for installation	The consultant
Shop Drawings	Fix dimensions, levels, routes and supports for installing the systems	Detailed, within the contractor's scope	The contractor
Coordination Drawings	Combine systems on shared drawings to find and resolve clashes	Combined routes and levels across several disciplines	The contractor or an appointed coordinator, per contract

What Are Tender Drawings For?

They show the proposed design and scope and form the basis of pricing. Their level of detail varies between projects, so they should not be assumed to be ready for direct installation.

What Do Shop Drawings Add?

The dimensions, levels, routes and details needed to install the systems.
Actual details of interfaces, supports and openings within the contractor's scope.
Interface and coordination points with the other disciplines.

What Is the Role of Coordination Drawings?

Combining systems on coordinated drawings to reveal clashes.
Showing routes, levels and the order of priority.
Recording clashes, decisions and approved solutions.

Does Drawing Approval End Coordination Responsibility?

No. Contractor and consultant responsibilities are set by the contract, and approval of one drawing does not mean every site clash is resolved. Later changes need managing and updating so the site does not work from an outdated revision.

4How Does Clash Detection Find Clashes Before Installation?

Clash detection is an engineering check for overlap between systems or violation of required clearances. It can be run on 2D drawings or on 3D models.

Technical office team reviewing clash detection results between HVAC, electrical and fire systems on a screen — Reviewing the clash list with the technical office team.

What Does Clash Detection Mean?

It is the identification of overlaps or breaches of required space between systems. A true geometric clash should be distinguished from an access or maintenance problem and from a sequencing problem, since each has a different fix.

Finding Clashes in 2D Drawings

Reviewing sections, elevations and levels.
Comparing duct, pipe and cable routes.
Identifying crossing points and issuing a trackable list of comments.

Using BIM Models Where Available

Federating discipline models and reviewing them in a shared environment, following project information management requirements such as ISO 19650 where specified.
Classifying clashes by type and priority.
Reviewing solutions and re-running the check after changes.

Whether BIM can be used depends on project requirements, the contract and the tools available to the parties.

What Clash Detection Cannot Settle Alone

Clashes that do not appear in the data or the models.
Design and code compliance decisions that need engineering review.
Real installation constraints that call for a site visit and dimension checks.

5A Technical Office Method for Managing MEP Coordination

The sections below set out a five-stage coordination method that a well-run technical office typically follows. Details vary with project size, contract and the tools of the parties.

Stage 1: Review Project Documents

Review drawings, specifications, equipment schedules and scope of work.
Identify missing information and visible clashes.
Prepare a log of requests for information (RFI) where needed.

Stage 2: Coordinate Across Disciplines

Combine HVAC, electrical, fire protection and other in-scope systems.
Review routes, levels, openings and maintenance space.
Hold coordination meetings and assign an owner to each clash.

Stage 3: Log and Close Clashes

Identify the clash location and its reference in the drawing or model.
Record priority, the person responsible and the target date.
Review the proposed solution and re-check the clash after the change.

Stage 4: Update Drawings and Review Approvals

Issue revisions under the project's document control system.
Follow up comments, approvals and open queries.
Verify that the latest approved revision is the one used on site.

Stage 5: Site Verification Before Closing Works

Confirm installation matches the approved drawings before works are concealed.
Document any difference or site change and deal with it through the proper procedure.
Update project records and as-built drawings per the contract scope, so they serve as the reference for preventive maintenance after handover.

6How to Choose an MEP Contractor That Can Coordinate, Not Just Install

A full-service contractor that delivers central air conditioning, fire fighting and electrical works under one contract reduces hand-over points between disciplines, which makes coordination easier. Van Tech delivers integrated MEP works, and you can discuss the coordination and clash management approach for your project with its engineering team through a technical site assessment. For general selection criteria, see our guide to choosing an MEP contractor in Cairo.

Technical Office Capability and Integration

Clear responsibilities for coordination and review.
A team able to read drawings from different disciplines.
A defined way of handling clashes and changes.

Documents to Request from the Contractor

A sample of redacted shop drawings that may be shown.
A template clash log or RFI register with sensitive data removed.
Procedures for review, approval and drawing revision control.
A statement of the tools and software actually used.

Technical Questions Before Contract

Who is responsible for coordination between disciplines?
How are clashes logged and who approves the solutions?
How are design changes managed after drawings are issued?
How is installation checked against the drawings?

7An Illustrative Scenario: Resolving a Duct, Sprinkler and Cable Clash

The scenario below is hypothetical, for explanation only. It is not a delivered project and contains no real figures.

The Problem

In a service corridor with a suspended ceiling, a main duct runs over a sprinkler line and a cable tray route. Each of the three drawings looks sound on its own, but once combined, the available height does not fit the insulation thickness, supports and maintenance space.

Analysis and Resolution

Identify the clash position, the levels and the architectural constraints.
Compare options on safety, function, maintenance and cost, such as changing the duct section, altering its level or rerouting cables.
Obtain the consultant's approval, including sprinkler distribution requirements, before installation.
Record the decision in the clash log and update the drawings.

Field	Example log entry
Location	Service corridor, grid reference as shown on the drawing
Disciplines	HVAC, fire fighting, electrical
Description	Main duct crosses a sprinkler line and a cable tray
Priority	High, because it affects the ceiling level
Responsible	MEP coordinator with the consultant
Status	Under review, then approved after re-check

Results and Lessons

The fix is made before installation, which would otherwise have become rework after concealment. The scenario shows why a log that records the decision and who made it matters, and why site verification must confirm the installed level matches the approved one.

Frequently Asked Questions

Shop drawings detail the systems of one discipline for installation, while coordination drawings combine several disciplines on shared drawings to find and resolve clashes. The same contractor may prepare both, depending on the contract.

References & Standards

Engineering review: Eng. Tarek El-Sayed, Technical Manager and Projects Lead at Van Tech
NFPA 13: Standard for the Installation of Sprinkler Systems
SMACNA: HVAC duct construction standards
ISO 19650: Information management using building information modelling (BIM)
IEC 60364: Low-voltage electrical installations

MEP Coordination
Shop Drawings
Clash Detection
Coordination Drawings
HVAC and Fire Protection Clashes
MEP Contractor

Engineering Takeaway

A clash costs least when it is resolved before it reaches site, through a documented coordination method rather than improvised decisions during installation. If your project is at detailed design or preparing for execution, the team at Van Tech can discuss MEP coordination requirements, the scope of shop drawings and how clashes are managed, based on your project documents, through a technical site assessment.

Van Tech engineering team is ready to review your project requirements.

Discuss Your Project with the Engineering Team

MEP Coordination: How Shop Drawings Prevent Installation Clashes