Building Information Modeling, or BIM, is a way of building a project digitally before anyone builds it for real. Instead of flat drawings, the project exists as a 3D model in which every duct, pipe, piece of equipment and hanger has a size, a location and a set of properties. For a mechanical or plumbing contractor, that model is the difference between finding a conflict on a screen and finding it in the ceiling.
What a 3D BIM model contains
A design-level model shows roughly where systems go. A fabrication-level model, built to LOD 400, shows exactly where they go: duct with insulation thickness, pipe with slope and fitting-by-fitting detail, equipment with its service clearances, hangers and supports in their actual positions. Advantage Engineering Technologies builds and coordinates models at this level in Revit and CADmep, because a model that is accurate enough to fabricate from is accurate enough to install from.
What BIM does for the contractor
- Coordination before installation. Mechanical, plumbing, fire protection and the other trades are brought into one coordinated model, and conflicts are resolved in Navisworks before material is cut. Read more about our MEP coordination drawings.
- Shop drawings that match the model. Plan views, sections and details come straight from the coordinated model, so the shop drawings and the model agree. See our mechanical shop drawings.
- Spool drawings and bills of material for prefabrication. Piping is broken into spools the shop can build, with a BOM purchasing can order from. See piping spool piece drawings.
- Fewer field changes. Routing, elevations and clearances are settled in the model, so the crew installs rather than improvises.
- An as-built record. When field conditions change, the model is updated, and the owner ends up with a model that matches the building.
Where BIM earns its keep
The payback is largest where space is tight and the cost of a mistake is high: hospital and healthcare corridors, mechanical rooms, laboratories, and industrial process piping. In those places, a conflict found in the model costs minutes. The same conflict found during installation costs a crew’s day, a change order, and sometimes a rework of work already in place.
What to look for in a BIM partner
- The model is built to fabrication level, not just to pass a coordination meeting.
- The people building it understand how the systems are installed, not only how the software works.
- Shop drawings, spool drawings and BOMs come from the same model, so they agree with each other.
- Questions are answered by an engineer who can read the contract documents and explain the reasoning.
Advantage Engineering Technologies does this work for mechanical and plumbing contractors across the U.S. and Canada, led by a licensed Professional Engineer. Learn more about our MEP BIM modeling services, or request a quote.
Frequently asked questions
What is the difference between a design model and a fabrication model?
A design model shows the intended system. A fabrication model, built to LOD 400, shows the actual components, sizes and positions a shop can build from and a crew can install from.
Which software does AET use?
Revit and CADmep for modeling, and Navisworks for coordination and clash detection. Deliverables can be issued in the formats your shop and your GC require.
Does the contractor need to run BIM software?
No. You receive drawings, spool sheets and BOMs in the formats you already use. The model stays with the engineering team, and you can have a copy if your project requires it.
Is BIM worth it on a small project?
It depends on the project. A small job with a congested mechanical room or a tight ceiling can benefit as much as a large one. A simple job with plenty of room may not need full coordination, and we’ll tell you so.