BIM digital mock-up: definition, standards and software for better construction

BIM digital mock-up, also known as digital mock-up, or BIM mock-up depending on the denomination, enables all those involved in a construction project to access the same computer file that models all the data relating to a building. The aim is to encourage collaborative work between participants on the same file, in order to preserve data, optimize costs and, above all, build better by considering all phases in the life of a construction, from design to management. This is the BIM process. Digital mock-up standards, such as the IFC file standard, enable interoperability between digital mock-up software, so that data can be preserved and returned to each stakeholder.

Do you confuse BIM with digital mock-up? What does the term BIM mean? What are the advantages of BIM and digital mock-up for each building-related trade ? Which BIM software should I choose? What are the requirements? We'll help you prepare for the challenges of Building Information Modeling in your field.

See all software Building Information Modeling (BIM)

Contents of our guide to digital mock-up :

What is BIM?

• Definition of BIM
• Objective: better manage all phases in the life of a construction project
• 6 advantages for building composition and operation

What is a BIM digital model?

• Definition of a BIM digital model
• A virtual 3D modeling principle enriched with data

Digital mock-up standards

• The standardized IFC file format
• The XP P07-150 or PPBIM standard
• 6 BIM models to enhance your digital mock-up

The benefits of BIM for each construction-related profession

• For design offices, architects and engineers
• For construction and civil engineering companies
• For building contractors and subcontractors
• For civil and structural engineers
• For component manufacturers and suppliers
• For surveyors
• For owners and developers
• For owners and asset managers
• For customers

Which BIM software to choose?

• How to choose your BIM software? 7 criteria to qualify your needs
• Comparative table of the 3 most widely used 3D modeling softwares

Awards and professional certifications

• A trophy for Archicad
• A BIM d'Or for Revit
• 3 nominations for Allplan

What is BIM?

Definition of BIM

BIM ( Building Information Modeling) is a work process that consists of :

• the modeling of all building data in a single digital file, the BIM digital model,
• a collaborative working approach between all those involved in the construction process,
• fluid project management and data production at every phase: design, materialization/execution, operation, even demolition,
• the use of BIM software to work on the same digital model.

Today, BIM is essential in a context where the various players in the construction industry work in isolation, in silos, using different files and producing different data, resulting in errors, wasted time, poor workmanship and budget overruns.

Regarding the three initials of BIM, the "B" for Building stands for Building, the "I" for Information.

The "M" stands for the 3 essential notions that enable construction trades to work together more effectively:

1. M" for Model means "maquette" in French. It expresses the need to bring together all building data and information in the same digital model, in a structured way. This is known as the Building Information Model.


2. "M" stands for Modeling. It expresses the collaborative work process, Building Information Modeling, which enables the expertise of the various parties involved to be pooled using the same data, based on interoperability between BIM software.


3. "M" stands for Management. It expresses the project management associated with the life cycle of a construction: it's about organizing, checking that the work process is fluid and that the data in the digital mock-up is shared. Building Information Management therefore stands for good construction project management.

Objective: better manage all phases in the life of a building

Prior to integrating the BIM process, the parties involved worked in a sequential engineering mode: one person's work started when the other's was finished.

If a change occurs during a construction phase, this can result in a considerable amount of back-and-forth updating of construction information, multiplying risks at all levels, and leading to additional costs.

The aim of BIM is to operate as a simultaneous engineering process: all players are involved right from the start of the project, so that they have a better understanding of the ins and outs.

A BIM approach consists in fostering understanding and communication between all players by making all information available to them: this access is made possible by the digital mock-up.

The digital mock-up clearly sets out all the phases and technical components of a project, so that specialists can work together intelligently to ensure that the project runs smoothly, taking into account any previous or future requirements of other experts. They can easily exchange and update information within a single file.

Each construction expert therefore knows all the information, elements to be designed, produced, built, managed or operated, and respective technical constraints, and can integrate them into his or her intervention phase. They can work in parallel with their colleagues without hindering the smooth running of the project - quite the contrary, in fact. The time factor changes dimension.

Each player works with the knowledge of the pre-established model for each phase of the project:

• feasibility,
• design,
• construction,
• operation/management,
• renovation, rehabilitation,
• demolition.

A project manager needs to be appointed to coordinate the project from the outset and ensure that everything runs smoothly. This specialist is often a BIM manager.

6 advantages for building composition and operation

To sum up, the main benefits of BIM can be seen at every level: design, construction, renovation, management and operation of buildings.

Benefit no. 1: simulate before making decisions

BIM technology is a great decision-making aid: by carrying out tests and simulations using visual representations, you can check the relevance of data, assess the budget required, eliminate duplications and errors, and reduce deadlines.

Advantage n°2: keep control of the project

For each stage of the project, you can accurately plan for degrees of complexity, requirements and anticipate difficulties. Unpleasant surprises are a thing of the past...

Advantage 3: Reduce costs and shorten lead times

Information is centralized and accessible to all players involved simultaneously, throughout the building's lifecycle. Understanding, collaboration and organization are optimized, problems are detected and avoided, and costs and lead times are reduced.

Benefit no. 4: save documents and energy

Writing information digitally means fewer documents, no more multiple versions. The use of a digital mock-up where data is centralized gives simplified access to the players involved, eliminating the repetition of time-consuming tasks.

Benefit n°5: greater profitability

Saving time, eliminating errors, collaborating: you cut costs and shorten delivery schedules.

Benefit no. 6: a qualifying European professional standard

The law governing public procurement in France, which came into force in 2017, gives project owners the option of imposing the use of digital mock-ups. It is up to the client to determine the objective, methodology and level of the mock-up.

Already initiated through European Directive 2014/24/EU of February 26, 2014, this approach reflects the desire to plunge building professionals into the era of digital transition, and ultimately, to make it a differentiating professional requirement.

What is a BIM digital model?

Definition of a BIM digital model

A BIM digital mock-up, also known as a digital model, is a computer file containing virtual objects relating to a building:

• it is a virtual representation of the building,
• It is an interactive 3D model of the physical and functional characteristics of a structure,
• The mock-up informs the various parties involved of all the technical specifics, such as spatial relationships,
• the file details all phases in the life of the building and all associated players,
• also known as an avatar, it simulates the reactions of the 3D objects and technical equipment involved in the construction,
• It enables upstream analysis and testing of the reactions of each mechanism, such as stability, energy performance and environmental impact,
• each trade specialist interacts with the file to update it and exchange information with other experts.

Mastery, centralization and sharing of information are the key elements of a BIM model: a single database stores all the information! Each expert adds to this database as the construction process progresses: updating technical information, new documentation, new equipment, etc.

A virtual 3D modeling principle enriched with data

Digital technologies have evolved: digital modeling goes beyond the notion of a virtual mock-up, or 3D representation in the strict geometric sense of the term, to create an intelligent, updatable and interactive working tool that can also be used over time.

When English speakers speak of digital mockup, we mean digital model, which includes all notions of objects:

• details of each object, such as walls, beams, doors, staircases, mechanisms, elevators, slabs, windows, etc.
• architectural and technical characteristics
• possible interactions between objects, commonalities in materials used, wall junctions, wind effects, etc.
• simulations, energy measurements, solidity, etc.
• organization and classification of information concerning these objects (e.g. site, building, floor, space),
• the evolution of construction stages, and even of the life of a construction by element.

The digital mock-up is integrated into the BIM collaborative work process and evolves over time: with each intervention or modification to the construction, the file is updated to enrich the database and reflect reality. This makes it possible to monitor the progress of a project and prevent potential risks in the event of an incident or delay.

Digital mock-up standards

The IFC standardized file format

We can clearly speak of a digital revolution for the building industry: the IFC format(Industry Foundation Classes) is a standardized file format that can be opened in the various dedicated building software programs.

It therefore facilitates communication between the various specialists and their tools. Players can collaboratively exchange and share information between software: the database structure is thus one of the BIM standards.

An IFC works on a semantic model based on the notion of object, an object representing each element that forms part of the building: floor, wall, space, window, ceiling, columns, etc.

Object modeling is what makes digital mock-ups so interesting:

• each object contains information such as its characteristics,
• interactions with other objects are indicated,
• each specialist can approach the object from his or her own or another's point of view (architectural, window nomenclature, structure, thermal view, axonometry, etc.),
• modeling enables information to be shared at every stage of the project's life cycle,
• no need to modify several files to update documentation.

The latest update of the IFC format is version IFC4, which has obtained ISO 16739 certification. This version of the IFC format brings its share of improvements:

• 113 more object classes (766 classes in total), including the boiler class,
• elimination of model interpretation problems,
• energy assessment and carbon footprint,
• integration of spatial zones,
• estimation of environmental impacts,
• the ability to model more geometric shapes, particularly for architects,
• complex shapes are easier to represent,
• more complete documentation.

Note: some software packages, such as Revit or Autocad, can read and write in IFC4 format. It is therefore important to use this type of software to benefit from the latest BIM improvements and standards.

Standard XP P07-150, known as the PPBIM standard

Under the impetus of AIMCC (Association des industriels des produits de construction) and Mediaconstuct, the PPBIM standardization committee of AFNOR (Association Française de Normalisation) published the XP P07-150 e 2014 standard.

The objectives of this standard are, in stages:

• create a common dictionary to establish terms that harmonize the naming of products, tools, practices and methods in the building sector,
• use the same terms for objects, their properties and their classification, to make better use of them in the digital mock-up,
• set up standardized object libraries, based on an established reference system,
• facilitate data exchange between construction professionals.

The XP P07-150 standard, known as the PPBIM standard, has been submitted to the European Committee for Standardization, and has become the focus for the development of data models produced within BuildingSMART international.

6 BIM models to enrich your digital model:

Model no. 1: 2D BIM for project design

At this level, we remain focused on 2D geometry requirements, with the possibility of trasncription in digital 2D plans.

Model no. 2: 3D BIM, modeling for collaborative working

The digital mock-up models the structure in 3D: already mentioned above, the IFC file facilitates access to the same information, and collaborative working.

Model no. 3: BIM 4D, plus time management

This 3D BIM model also includes a timetable, enabling work to be scheduled and progress visualized in real time.

Model no. 4: BIM 5D to associate costs

This BIM 4D model also includes budget and expenditure data: calculations can be automated to assess costs and cash flow forecasts.

Model no. 5: BIM 6D to integrate the sustainable development dimension

This 5D BIM model also integrates a building's sustainable development dimension, such as energy performance estimates.

Model 6: 7D BIM for monitoring and maintenance

This model is designed to help property managers, suppliers and subcontractors during all phases of post-construction maintenance: BIM 7D provides all information on the machines present and specific data on procedures such as manuals and standards, in order to monitor the condition of the entire building and ensure its good health.

The benefits of digital mock-up for every construction trade

For design offices, architects and engineers:

• visualize a construction project at every stage,
• view the building from all points of view,
• design by analyzing the model from every angle,
• check and simulate the life of objects,
• correct defects and avoid errors,
• generate 2D plans on the fly,
• comply with standards,
• have permanent access to all information (budget, timing, etc.),
• anticipate accordingly, in particular to meet energy performance requirements,
• apply a sustainable development approach.

For construction and civil engineering companies:

• take delivery of the digital mock-up or produce it themselves (e.g., unify different digital mock-ups),
• Examine the site prior to construction,
• identify high-risk areas upstream, so that appropriate safety measures can be put in place,
• evaluate the design to identify possible errors,
• use the database to prepare the site,
• check progress and control costs in real time,
• regulate the supply chain,
• reduce delivery times by using off-site prefabrication.

For building contractors and subcontractors:

• identify any errors or omissions,
• gain an overall view of the project, as well as of interactions between participants,
• analyze interventions and detect potential negative interactions between trades,
• modify the digital mock-up, rather than reacting once the project has progressed to a given stage,
• see the effects of corrections on the entire BIM model,
• synchronize design and construction,
• know what materials and resources are needed for each stage of construction,
• smooth the flow of equipment and materials deliveries,
• optimize the timing of interventions and orders placed with subcontractors.

For civil and structural engineers:

• receive a usable model, without redrawing plans,
• know the structural elements thanks to the 3D model,
• modify the structural model, which the architect will then transfer to the architectural model, directly in the digital mock-up,
• draw up reinforcement plans based on a pre-established, functional BIM model for designers,
• anticipate fabrication and shaping by launching them remotely,
• reduce the risk of errors,
• save considerable time for the entire engineering office.

For component manufacturers and suppliers :

• understand the needs and expectations of designers, constructors and maintenance personnel,
• provide objects that can be used in a BIM digital model,
• offer quality objects containing relevant and structured information, making them easier to manipulate in the model,
• offer usable objects for all stages: design, construction and maintenance.

For surveyors :

• create an initial digital model enriched with 3D data upstream of the project,
• boost quality by evangelizing building sector expectations, such as sustainable development,
• facilitate a change in mentality in everyone's interest (collaborative work, interoperability and benefits for all parties involved),
• guarantee the restitution and transition of information for better territorial management,
• propagate the correct use of an exploitable model framed according to decisive criteria,
• be able to intervene at every stage and include its Carrez law measurement or volume division in the model,
• be in a position to intervene to ensure that the building constructed meets the established specifications.

For owners and developers :

• extract information to validate feasibility in terms of budget and time,
• improve the building by correcting functional or environmental anomalies,
• evaluate in real time the repercussions of an incident, such as design modifications,
• promote the involvement of all experts through better understanding (building quality is everyone's business).

For owners and asset managers:

• benefit from comprehensive information at every stage in the life of a building,
• anticipate installation possibilities or obligations,
• better manage their property,
• carry out effective maintenance work.

For customers:

• Reassure themselves of the smooth running of a project at every stage,
• benefit from lower costs,
• reduce project delivery times,
• consume less energy,
• reduce waste and carbon emissions,
• enjoy optimum safety during use,
• increase building performance.

Which BIM software to choose?

How do you choose your BIM software? 7 criteria to qualify your needs:

Criterion n°1: the software's good reputation

If the name of a software package is often mentioned by different specialists in complementary fields, it's a good sign that it's being used successfully by different players.

It's a good idea to rely on software that promotes the use of best practices through regular updates, such as Revit, which benefits from significant new features and improvements.

Criterion no. 2: interoperability with other software

Should your BIM software be able to work with third-party software such as Microsoft Excel, Word Crystal Reports for reporting, project management or workflow software?

The whole point of BIM and digital mock-ups is to exchange data that can be read by other players in the construction industry: your software must be able to read the IFC format in particular, to be compatible with other software, and manipulate objects based on the same nomenclature.

In addition to the IFC format, you can also ensure that you can read and write certain other formats: IFCXML, IFC 4, PDF (Acrobat Reader) JPG, TIFF, BMP, PNG, RVT (Revit software), DXF/DWG and 3D DWG, etc.

Criteria 3: Real-time collaborative working

Criteria 4: Functionality

Depending on your business and working methods, you should also consider the following points:

• for architectural design, you need to be able to take advantage of 3D design visualization and a free-form model design tool,
• on the engineering and MEP manufacturing side, you need software that integrates manufacturing documentation,
• from a structural point of view, functionality capable of managing reinforcement constraints or gravity analysis, for example,
• for the construction part, modeling and construction coordination functionalities are essential.

We refer you to the BIM model chosen beforehand.

Criteria n°5: BIM object library

In 3D object catalogs, professionals download ready-to-use objects to insert into their digital mock-up model, instead of creating them.

To take advantage of the time saved, however, you need to check that the format of these objects is compatible with your software.

These 3D object libraries dedicated to BIM generally offer IFC, 3DS and RVT formats (Revit software format, which also reads IFC):

• Autocad and Revit take the cake for variety, with no fewer than 16 sites and almost 70,000 objects,
• for Archicad, 10 sites and 1021 objects,
• 9 sources are available for Sketchup,
• Allplan has 4 suppliers.

Criterion no. 6: Ergonomics and ease of use

If Revit Architecture, one of the most advanced BIM software packages, requires more training time than Allplan, ArchiCAD or Sketchup Pro, it's worth considering how it compares in the long term: we refer you to the points already mentioned.

Criteria 7: Customer support, guides, resources and tutorials

We always learn better when we have support to help us better understand the software. On this point, we note, for example, that the number of videos on Sketchup pro and Revit is higher. An element of reputation?

It's up to you to find out...

Note: prices change from year to year as improvements, compatibility and new features are added. We advise you to compare offers.

Comparative table of the 3 most popular 3D modeling software packages

Poll: Allplan, Revit or Archicad?
The Hexabim professional community responds:

See all software Building Information Modeling (BIM)

Professional awards and certifications

We feel it is useful to provide you with this information, which may help you in your choice of software. Indeed, publishers' efforts to provide the best BIM software are rewarded:

A trophy for Archicad

ArchiCAD has won a trophy in the design tools category at the 2016 digital transition awards organized by the PTNB (Plan de Transition Numérique dans le Bâtiment).

A BIM d'Or for Revit

The BIM for FM experimentation project, which uses Revit in particular, was awarded a BIM d'OR in 2016, under the watchful eye of professionals such as PTNB president Bertrand Delcambre, and the 300 players representing architecture, construction, engineering, private and public project management. Note: Revit has also been nominated several times in different categories at the trophies for digital transition.

3 nominations for Allplan

Allplan has been nominated several times for the trophées de la transition numérique (digital transition awards), but did not win in the following categories:

• design tool,
• structure and shell,
• business tools for project management and operations.