BIM, standing for Building Information Modeling, corresponds to a collaborative approach centered around a digital model of a building and its associated information structure.
‍
Implementing a BIM approach, requires the digital model to incorporate a structured database of project information, alongside defining a specific coordination methodology.

This way of working is intended to extend the entire cycle of the building structure: in design, construction, management, operation, maintenance and demolition. Thus, all building actors can benefit from it (architectural agencies, design offices, operators, inhabitants, etc.).

The level of detail (or LOD - Level Of Detail) corresponds to the geometric precision of a model, defined by the precision of the 3D objects it contains.
‍
This level of precision makes it possible to obtain varying degrees of geometric information. It can be adapted zone by zone or by category of elements represented in the model, in order to tailor it to the specific requirements of a project.
‍
There are 5 different LOD levels (LOD 100, 200, 300, 400, and 500). Even if no nomenclature exists on this point, we note that certain classical uses emerge for each of these standards during the design, construction and operation phases.

Depending on your needs, the right elements will be modeled, allowing a better cost-management and production time of the deliverable, without limiting their use. Thus, the following elements can be represented:

• The interior structure (floors, walls, beams and columns) and the exterior structure (walls, doors, roofs and windows);
• The Architectural body.
• Technical and terminal networks (HVAC, Electricity, Plumbing and the Fire sprinkler system);
• Industrial equipment (machinery, production lines, etc.).

A set of documents govern a BIM process by covering the life cycle of the structure. Among them, we can cite the functional specification document, the charter and the BIM Convention.
Their role is to guarantee compliance with the BIM objectives set by the project owner and to organize coordination between the various entities that work around the 3D model.
To find out more about this, we invite you to read our article on BIM documents.

Since digital models are created in specific software, they have a so-called “native” format corresponding to each software (Revit, Autocad, Allplan, etc.).
In our BIM modeling process, the export can be done in interoperable format (IFC) or in the native format of the Revit software, which is the one we use to model.
For the production of 2D plans, we use Autocad and offer plans in .DWG format.

The building's point cloud is used as a 3D modeling layer of reality during the modeling and quality control phases of the 3D model.
It thus makes it possible to rely on a precise and representative footprint to produce “As-Built” modeling (as built). We are talking here about a “scan-to-BIM” method.
During the quality control phase of the model, the captured point cloud will be used to detect:

• Missing surveyed areas;
• Discrepancies between the point cloud and the model;
• Errors in the interpretation of the modeled object.

These various control methods will make it possible to produce a quality deliverable that complies with the modeling specifications.