Today, it will not be a blog post but an invitation.

Next week, the BIM World event will be held in Paris. This event will gather a large panel of architects, engineers, contractors, manufacturers, and software developers, all interested in Building Information Modeling and related technologies.


I will be representing my company Ingérop here, and will present our last projects using BIM.


I will also give a short speech “Développer les compétences du BIM” about implementing Building Information Modeling in an engineering consultancy firm, and the consequences of this paradigm shift.

I would be happy to meet you there and exchange with you, so if you happen to be in Paris next week, the exhibition will be held on Wednesday and Thursday at the CNIT Center in La Défence.

See you there ….

Trying out Autodesk 360

I was recently searching for a web-based collaboration platform to quickly exchange models between people from different organizations, and since Autodesk had just release its new flavor of Autodesk 360 website, I gave it a try.

The first impression when logging to the new Autodesk 360 Hub is the integration of social capabilities. Every modification is displayed in a handy timeline for everyone to see. I had some prior experience with the project management tool Basecamp (, and I see in this new version of Autodesk 360 some of the features that made Basecamp so successful.

These features, along with the new domain name (, show the effort of Autodesk for producing a complete web-based solution for reviewing BIM content.
Everything in Autodesk 360 is organized around projects, which come with their own calendars and wikis. To work with Autodesk 360, you first have to create a new project and invite members to this project:


After adding a nice logo to your project, you can create folders and start uploading Revit models:

uploadFilesThe upload is pretty quick, but the file has to be processed to be visible through your browser.


Every members will be able to see and download files uploaded in their project. These model also appear in the timeline for everyone to see or comment them.


Once downloaded and processed, the model become visible in the embedded viewer browser. This is where the main feature of Autodesk 360 lies. The 3D model run smoothly, and the whole experience is nearly the same than with a desktop-base viewer.


Along with showing the 3D model, Autodesk 360 display every sheet embedded in the uploaded Revit model. My only wish here is to be able to annotate the drawing just like we do in Design Review, but I hope this will be available in a future release.


Another nice feature, the 3D viewer allow us to isolate elements by categories and display every elements properties.


It’s still miss the ability to create section, and most of it, to be able to download Revit sheets as pdf for an easier reviewing, but I don’t lost hope.

During my whole experience, I just encounter one problem, with my model freezing in generating preview mode just after downloading it.

On the whole, the new Autodesk 360 come really close to a mature web-based model reviewer, and I see a lot of new applications coming to life, especially for the one who are not spending their days in front of Revit, but still need a quick access to the model.

My version of the Living Cube

Designed by Till Ewert Koenneker, The Living Cube is an assembly of shelves, storage space and a bed. Tightly integrated in an ergonomic cube, its timeless design allows it to be used in any space and situation.
After encountering the work of Till Koenneker, I decided to use it as an inspiration to draw the same one for myself.
The main idea is to design a piece of furniture, producing drawings with a software usually used for steel detailing. My goal is to automatically produce shop drawings of every parts of the finished product, directly from the model. These drawings are then to be send to a joiner’s workshop for the production of parts that I can assemble myself, just like any ready-to-assemble Ikea-like funiture.
I’m not using Tekla Structure on a regular basis, but I know its power for producing shop drawing for timber or steel structure, and its caracteristics fit my needs for this project. It will be a good occasion to hone my Tekla skills.
I started with a first sketch on Tekla Structure, trying to find the best proportion for my needs. I came up with a first version, and used 3D Max to render it.

RenderingI then used the Tekla model to produce general drawings of my project, and submitted this first version to someone who is used to design and build pieces of wooden furniture to get some feedback. His very precious advice helped me to draw a second, more constructible version of my loft bed. These drawings are also available here.

VersionI was then able to create a detailed shop drawing for each part of my assembly.

PartSadly, this project is still in its development phase, mostly due to my lack of knowledge in furniture design and joinery work. I hope to be able to restart it someday, when I will have time to draw some new version.

Level Of Development

One of my current project made me think of talking about the so-called LOD of a building model.

The LOD (Level Of Development or Level Of Detail) was first described on the Model Progression Specification (MPS) development by Vico Software in 2004. This document aimed to create a framework in order to define standards for any building model delivery. It answers, for each phase of a project, the following questions :

How accurately the model should be detailed ?
Who is responsible for modeling a particular element ?
What information should be integrated in the model ?

In 2008, the American Institute of Architect  after further developments on this project, released their official version, the E-202 “Building Information Modeling Protocol Exhibit”.

This paper divided the Levels Of Development in five categories, each one describing the elements expected in the model, the corresponding state of development of the project and the possibilities for producing construction documents and building analysis. They are defined as follows:

LOD 100: Conceptual design
The model represent the general massing of the building, with area, volume, orientation and so on.
This model can be used for solar and early energy analysis.

LOD 200: Design development
All systems are modeled with their general size, location, orientation and approximate quantities.
It can be used for general performance analysis and early calculations.

LOD 300: General construction documents
In this model, elements are accurately integrated, with their actual size and location. It is suitable for producing general assembly and construction drawings.
This model allow precise analysis and simulations on every element and system. It can also be used for coordination and clash detection.

LOD 400: Fabrication information
Every element is modeled for fabrication purpose.
The model is suitable for shop drawings
It can be used for direct production and construction scheduling.

LOD 500: As-Built model
The BIM equivalent of As-Built drawings. In these models, elements are represented with all technical information needed for maintenance and procurement.

These descriptions are indicative, and do not prevent the BIM Manager from describing model deliverables more exhaustively. They are more like guidelines for creating an accurate BIM Implementation Plan, with precise indication for each actor about his responsibilities in the development of the model. To do so, these guidelines come with a Model Element Table like this one :


This table defines the required level of detail for each element of a building model at each phase/LOD of the project.

I am unsure whether or not this “Building Information Modeling Protocol Exhibit” can be used as it for any project, especially in France, where construction practices may differ from what the AIA first defined. However, it is a great tool for creating an accurate BIM Implementation Plan. It describes well the expected state of the model for each phase and may come in handy when working with companies which have not yet integrated all requirements of a BIM workflow.

About Tekla Structure

I just came out of a week of training on Tekla, and I feel like talking about it. As you might expect, Tekla Structure is a BIM application mainly oriented toward structural modeling and detailing. Originally design for modeling steel structures, it’s now also covers concrete structures, execution drawings extraction, and model reviewing features.

Far away from code-driven geometry and other parametrical modeling stuff, Tekla is practical. Ok, you cannot generate thousands of roof panels with a nice piece of .NET, but a least, you don’t spend fifteen minutes to draw a wall. This pragmatic approach combined with powerful drawings generation features, made Tekla a real construction-oriented BIM software.

Since its acquisition by Trimble, a company mostly knows for its GPS, lasers and other positioning hardware, Tekla had developed a great deal of applications for the construction site. Fully integrated with the Trimble hardware, it allows adding topographic points to a model, generate new coordinates for the layout, and export them in a Trimble tablet to implant them directly on site.

But what impresses me most is the execution drawing generation. Once you have drawn the few beams of your future greenhouse (for example), liked them together with the automatic assembly tools, you are just a click away from generating all the drawings you need. Basic templates include general arrangement drawings, single-part drawing or assembly drawings, but you can also fully customize your production regarding the needs of your design office.

But being pragmatic does not in any way prevent Tekla from being smart, and it comes with a large set of parametric components allowing designing quickly every details of our structure. And if these components are not enough, you can also design your own, with an interface looking like the family editor of Revit.

Nowadays, Tekla is broadly integrated into design offices for steel detailing (even in France …), and since its acquisition by Trimble, it seems to becoming the most site-oriented of BIM software.

Using Digital Project

As Franck Gehry was designing is extraordinary museum in Bilbao, he had to use the only 3D modeling software available at this time, CATIA (Computer Aided Three-dimensional Interactive Application). This software, develop by the French company Dassault to help them design their aircrafts, is still nowadays the leading product for designing cars, aircrafts, or any other product with some mechanical parts.

Since CATIA is not made to design building, Franck Gehry had to use his own plugins, and created Gehry Technology to develop them. Integrated into CATIA, these plugins became the BIM software known as Digital Project.

Just to make things clear, Digital Project is the most powerful BIM software. When you start using it, you understand why the design of some of the most iconic buildings of our times involved Digital Project.

It is able to deal with very complex shapes, really large and complex models, and came with all the utilities embedded into CATIA, from PowerCopies to optimization algorithms. Buildings models can be exported in IFC, and it provides a complete set of tool to design basic architectural elements. It is not limited to buildings, but works also great with infrastructures like this footbridge:

Automation can be easily done with .Net code, and open limitless possibilities for designing complex shapes and repetitive patterns.

But it also has its drawbacks. Compared to Revit, or other traditional building modeling software like Alplan or Archicad, it’s expensive, not user friendly for a second, and frankly, not very pretty.

Dassault System had recently bought the development part of Digital Project, and I expect a new release of Digital Project based on CATIA V6 soon enough.

Industry Foundation Classes

Anyone who has worked in the BIM field may have eared something about Industry Foundation Classes. Yes, you know, this little logo…

Generally, it appears when we try to export a building model from proprietary software to another. The IFC exchange format allows us to convert files and, with some luck, open them the other software.

But what really is this IFC file format, and why everybody talk about it ?

Developed by Building Smart, a non-profit association of architects, civil engineers and IT specialists, IFC is a data model specifically designed for building information modeling.

In other terms, it’s a series of definitions, explaining how describe any building element in order to make it comprehensible by a computer. But while each BIM software relies upon its own very private data model to define a building, the IFC data model is open, and freely accessible by anyone here.

These definitions create a language readable by a computer, and written as a text file. This file is even readable by human being, and look more or less like this:

#66= IFCCARTESIANPOINT((-17261.0669833266,3274.73863321424,0.));

#68= IFCAXIS2PLACEMENT3D(#66,$,$);


#70= IFCCARTESIANPOINT((9430.2775637732,0.));

#72= IFCPOLYLINE((#5,#70));

#74= IFCSHAPEREPRESENTATION(#43,'Axis','Curve2D',(#72));

#76= IFCCARTESIANPOINT((9430.2775637732,-100.));

It’s not very convenient, but with some pain, we can find a wall here,

#209= IFCWALLSTANDARDCASE('0EiAvIo0LBOBfvSD8E4HST',#52,'Basic Wall',$,’200 mm’ ,#181,#207,'177171');

create by an extrusion like that,

#92= IFCEXTRUDEDAREASOLID(#90,#91,#15,8000.);

and place at the point define like this:

#76= IFCCARTESIANPOINT((9430.2775637732,-100.));

I have worked some times in order to understand this language, and if I’m still not speaking IFC fluently, I was able to improve myself a little. You will find the result of my work here.

There is plenty of IFC’s approved software, but if everyone is compliant, some are more compliant than other. For example, Revit was well known for its really poor implementation, but I have heard that Autodesk have made great improvement in the 2013 version, I still have to look at it.

For my part, the best implementation I have ever be able to test is the plugin for Grasshopper made by Jon Mirtschin called Geometry Gym. Fully compatible with the latest version of IFC (IFC2x Edition 4 Release Candidate 2), this plug in transform Rhino in a full scale BIM software. This plugin deserve at least a whole article, so I will came back to it.

The IFC model is still in the development part, and is currently in the process of becoming the official International Standard ISO 16739.

If it’s not the leading format in the BIM business, the IFC format is a really interesting attempt to create an open exchange standard, and some software like Solibri Model Checker have understood it well enough to use IFC as the only input models format.

About my job

As a part of the building information systems department, I’m involved in the development and implementation of BIM in our design process. This implies various tasks, from finding new software solutions to assure in-house user support.

The main part of the job, the so-called BIM Manager thing, is to organize the design process around chosen BIM software. Creating model templates according to the specification of the company, organizing multi-users modeling around a main model and providing users support are among the everyday tasks.

Apart from the in-house building design, we have also created BIM specific solutions for design offices or general contractors. These solutions range from synthesis and coordination at the early stage of a project to BIM facility management on existing buildings.

Finally, I try to keep in touch with all the BIM-related solutions, following the evolution of the information technology for building construction, from code-driven form-finding to on-site management using tablets and cloud-hosted solutions.