MEP shop drawings show how the mechanical, electrical and plumbing services will actually be installed on a project: the routes, sizes and levels of pipes, ducts and containment, the equipment the contractor has chosen, and how everything fits around the structure, the ceilings and the other trades. They are prepared by the M&E contractor from the consultant's design drawings and reviewed before installation starts. Getting them right, and approved on time, is what keeps the site working to programme. This guide covers what goes into them, how coordination works, which software to use and how to get through the review cycle quickly.
The required content, format and review process come from your contract, the specification and the project's BIM requirements. Check those first. This guide covers the practical side.
Design drawings, shop drawings and as-builts
| Drawing | Prepared by | Shows | When |
|---|---|---|---|
| Design drawings | Consultant | What is required: systems, capacities, indicative routes | Tender and design stage |
| Combined services drawings | Contractor (all M&E trades) | All services overlaid and coordinated | Before trade shop drawings |
| Shop drawings | Each trade contractor | How it will be installed, with chosen products | Before installation |
| As-built drawings | Contractor | What was actually installed, with every change | Through construction, issued at handover |
What an MEP shop drawing should contain
- Routes, sizes and invert or centreline levels of pipes, ducts and cable containment
- Equipment positions with the selected make and model, and access and maintenance space
- Supports, hangers and fixings where the specification asks for them
- Sleeves, openings and penetrations through walls, slabs and beams
- Connections to equipment and to the other trades
- Ceiling heights and the clear zone the services must fit within
- Sections at congested areas such as corridors, plant rooms and risers
- Legends, notes and references to the design drawings and specification
- A title block with the drawing number, revision and status
How coordination works
Coordination comes before trade shop drawings. The usual order is:
- Collect the latest base information. Architectural and structural drawings or models, the ceiling layout and the design drawings for every trade.
- Model or overlay all the services. Fire protection, ACMV, electrical, ELV and plumbing and sanitary on one combined drawing or in one federated model.
- Find and resolve clashes. Gravity drainage and large ducts usually take priority, because they are the hardest to reroute. Smaller pipes and containment move around them.
- Agree the combined services layout with the consultant and the main contractor.
- Issue trade shop drawings from the agreed layout, so every trade draws to the same coordinated positions.
When the design changes, update the combined layout first, then the affected trade drawings. Changing a single trade's shop drawing on its own is how new clashes appear on site.
Revit MEP or AutoCAD?
| Revit MEP (with Navisworks) | AutoCAD | |
|---|---|---|
| Best for | Projects that need a coordinated model, clash detection and model-based quantities | Smaller packages and 2D drawings |
| Coordination | Federated models and clash runs in Navisworks | Overlaying layers and sections |
| Changes | One model change updates plans, sections and schedules | Each affected sheet is edited |
| As-builts | The model is updated to the installed condition | Sheets are redlined and redrafted |
Follow the contract and the project's BIM execution plan. Where a model is required, keep it as the single source and produce the sheets from it.
Getting through the review cycle
Most delay comes from resubmissions. To keep them down:
- Submit complete packages. A drawing without product data, sections or references usually comes back.
- Track every comment. Keep a comment register per drawing, record how each comment was closed and refer to it in the resubmission.
- Cloud and list the revisions. Make it easy for the reviewer to see what changed since the last issue.
- Keep one drawing register. Drawing numbers, revisions, status and dates in one place, so nobody installs from a superseded sheet.
- Plan around installation dates. Work back from when each area is due to be installed, and submit early enough to allow for a revision cycle.
Common mistakes
- Drawing trade shop drawings before the combined services layout is agreed
- Working from superseded architectural or structural drawings
- Leaving out access and maintenance space around equipment
- Missing sleeves and openings until the slab is cast
- Not recording which comments were closed in a resubmission
- Installing from a drawing that was never accepted, or from an old revision
- Leaving the as-built record until handover. See the as-built drawings checklist.
Related guides
- As-built drawings checklist for MEP handover
- CORENET X for MEP and BIM submissions
- Dedicated estimator or in-house hire?
How Newham can help
Newham provides dedicated BIM modellers and drafters who prepare MEP shop drawings, coordination models and as-built documentation in Revit MEP, AutoCAD and Navisworks, working in your templates, title blocks and naming conventions. They cover fire protection, ACMV, ELV and wet services (plumbing and sanitary). A dedicated drafter is billed monthly in SGD, with no recruitment or setup fees and the scope confirmed in writing. See MEP shop drawing services, or book a discovery call to plan your drafting capacity.