Friday, 15 March 2013

What is BIM? (Part 1 - Building Information Modelling)

In the context of ArchitectureBuilding Information Modelling (BIM) is a design methodology, which enables all of the design details, decisions and characteristics to be held within a collaborative digital model and information package. Having all of the information centralised in one core model will inevitably lead to improved design and document efficiency. It is this added value that takes BIM beyond that of a simple 3D visual model.

Designed by and Property of Danny McGough
I'm going to open with a few statistics but don’t be too frightened, 4 stats and I'm done!
The knowledge of BIM within the construction industry is on the rise, the recent NBS National BIM Report 2013 states that only ‘6% of the industry were neither aware nor using BIM’ in 2012, compare this to previous years of 21% and 43% in 2011 and 2010 respectively it is clear that the awareness of BIM amongst construction professionals is rising. Looking at these particular statistics it does paint a promising future for BIM.

Designed by and Property of Danny McGough
However following on from this, in the same NBS BIM Report 2013, the statistic that ‘74% of the industry is not clear enough on what BIM is yet’ does mean that we’re not completely past the ‘What’ stage just yet for all construction professionals. It’s with this in mind that has led me to write this week’s blog, ‘What is BIM?’ In the context of Architecture Building Information Modelling (BIM) is a design methodology, which enables all of the design details, decisions and characteristics to be held within a collaborative digital model and information package. All of the design and project information can then be shared, accessed and even altered live, facilitating an efficient and fluid collaborative design and asset management process across the whole life cycle of a building. For the wider range of parties involved the concentration may be more on the 'Information' sharing aspects of BIM.  A predominate aspect of BIM which continually needs to be expressed and driven home is that the 'Information' side of BIM is just as important as any design model. Working within a BIM environment, adopting BIM information sharing protocols, collating the data in an interoperable format, and utilising documents such as BuildingSMART's 'Project Execution Plan' into a project aims to improve how information is shared amongst all varying parties involved in an efficient interoperable manner, regardless of whether you're the Architect or the contractor.

A core feature of working within a BIM environment is the drive towards encouraging multi-disciplinary collaboration from the very outset of a project. The benefits of all disciplines working together within one core BIM environment are multiple. A major issue that is experienced within non BIM design processes is the matter of conflicting design issues; the ethos of having a core central BIM model is to facilitate a smoother transition through these issues by identifying conflicts earlier on in the project stages thus reducing the negative effects on schedule and costs. From an early stage projects can be visualised allowing the client and designer alike to gain an appreciation of how the design is going to materialise, this allows for important design decisions and alterations to be made at an early stage where the cost repercussions are little cost or even zero. The efficiency of the effects of changes within documentation or design is greatly improved as any changes made which are linked to the main BIM package will be carried through and updated to all corresponding linked documents and models automatically.

Designed by myself, Danny McGough
To the right you can see a graphical example of an 'Independent Separated Design Environment'. This simple graphical representation expresses the chaos when all parties are working independently of the others.  Having the design process completed within a BIM environment using 3D BIM models with a core 3D BIM model at the centre of the project leads to multiple benefits post model creation. The models can be analysed allowing for a multitude of model interrogations to take place including; energy analysis, structural analysis, accurate schedules and quantity take-offs to name a few. It is argued that by using BIM processes for building projects it will improve the energy efficiency, improve the scheduling, facilitate a reduction of waste and possibly paramount to this, a reduction in costs.

Below is another graphical representation , of a  'BIM Collaborative Design Environment' showing how a BIM core model and digital information package can assist the project team to deliver a fluid fully collaborative project.

Designed by myself, Danny McGough

In summary, through carrying out all of this pre-construction design analysis and interrogation the result will be a reduction in conflicts and changes made during the construction phase which usually will have a detrimental effect on a project in terms of wastage, quality, time and costs. At the same time the stringent energy analysis that can take place in the early stages of a BIM project aims to improve the performance of a project in regards to low impact design. And finally post project completion the BIM model can continue to be utilised by the FM team to assist in the management of their assets in an environmentally conscious manner.

I’ve migrated to gain further control to expand the content; you can find my new polished website at;

Please feel free to come over and look at the new set up and design as well as the latest article on Sustainable Urban Drainage Systems for Green Roofs (SUDS).   The article is a follow up to the previous article on To Green of Not to Green? This article will be focusing more on the technical aspects, in particular Sustainable Urban Drainage Systems, otherwise known as SUDS.

All the previous articles on architecture, tech and BIM are over at the new site

Thank you for visiting Architect-BIM and I hope you continue to follow us over at the new site-

What are your thoughts and experiences on BIM today? Is BIM something that is completely new to you, a foreign confusing topic or are you in the, we love it and were flying with it category?

I'd be really interested to hear your thoughts below in the comments as it would be great to hear where you are all coming from so we can keep the discussions and articles moving.

Information/opinions posted on this site are the personal views of the author and should not be relied upon by any person or any third party without first seeking further professional advice. Also, please scroll down and read the copyright notice at the end of the blog. 


  1. really good read. I understand BIM a bit better now thanks to your pictures

  2. Thanks for the great intro on BIM! It seems the movement toward mandatory implementation of BIM is inevitable. Is Revit the main software for BIM implementation and do you think this could be a weakness in the long run? What's openBIM about and how do the various stakeholders take part in it?

  3. Thank you for the encouraging comments, it's really appreciated.

    You've hit on some important discussions which are continually being debated within BIM circles at present. Firstly to answer your first question I’ll refer back to refer back to the same NBS BIM Survey report 2013 as mentioned in the Article, the survey reports that 63% of the participants were using Autodesk products to produce their CAD drawings, with 18% of that figure being specific to Autodesk REVIT. Autodesk do have a big share of the market but they’re not the only players.

    This topic directly leads onto the debate between open BIM and closed BIM. Closed BIM generally refers to when BIM processes are carried out on a single platform where as open BIM refers to when the BIM environment crosses multiple platforms regardless of the software vendor. In essence open BIM specifies that information should be shared/exported to a non-proprietary format, such as IFC’s. REVIT can sometimes be referred to as closed BIM, but this is not a clear defined point as REVIT does have the capability to export file types in the ‘open’ BIM IFC format. This is a vibrant area for debate which I will discuss in further detail in a later article.

    1. The question of what Open BIM means is worth a short comment here. Mr. McGough has expressed one version. The other I have heard takes "Open" in the same sense as "Open Source", wherein the software code is available to all free of charge, and independent developers are encouraged to modify it for their own use, and submit suggested changes to a volunteer, or semi-volunteer organization for incorporation in the "official" version. IFC is one example of such an initiative. In it's case, buildingSMART International's Model Support Group is the organization. Another example is OpenOffice.

      However, IFC cannot write a file on it's own, and it cannot read one. It is an information exchange format only. Analogies might be "html", which needs a browser, or something like it, to be useful. Or "dif", which needs a database or spreadsheet application to be useful. I know of no fully functional BIM authoring and editing tools that are "open" in this sense. I would love to hear otherwise. However, I believe that there are folks working towards such tools.

      IFC is also not completely "open" in the same sense as OpenOffice. The schemas are publicly available. But suggested for changes from the world at large are not necessarily accepted, acknowledged, or acted upon. Many organizations are represented in the Model Support Group membership, but membership in bSI and the MSG (or a contractual relationship with them) are prerequisites for direct participation in IFC's development. Anyone can use it, but building owners, designers, and contractors only use it directly when they are wearing their computer programmer hats. The rest of the time, they use the code indirectly, through other BIM viewing, design, or analysis software.

    2. Thank you Lighthart, its great to have some more input and discussion on the deeper technical details of 'open' and 'open source'. As you've highlighted there is some very technical aspects to this topic beyond that of the general 'open' or 'closed' BIM discussions. What I feel your delving into is to the depths of an experienced BIM practitioner or even a programmers expertise.

      In terms of what I was attempting to highlight was in regards to 'open' and 'closed' BIM in general terms, at a level which would be easier to digest, concentrating on the interoperability aspects of BIM. This is where I feel a considerable amount of the current debate lies. IFC as you say is a standard which has been developed by Building SMART international which if adhered to, enables for the exchange of models and information between multiple software types, in essence achieving interoperability. The voices behind 'open' BIM are actively encouraging BIM practitioners to utilise the IFC data format, in the hope that no one software vendor will have a monopoly on the software market. It is argued that this topic of interoperability of file formats and software packages will be a major factor in determining BIM's success and whether its a smooth transition from isolated design practices to a truly collaborative BIM environment.

      As I mentioned I will be looking to cover this topic further within this blog at a later date and would be happy to hear your thoughts further so feel free to PM my email

  4. Great discussion! Really enlightening and useful. I was wondering if you could include a basic intro with pictures to explain open BIM and IFCs and interoperability and stakeholders. I understand with your help, what BIM is used for and how, but what's analogous to openBIM? Perhaps I am getting confused because I was a programmer and I might be confusing things with the terms open source. But perhaps there are several layers to the word 'open' and BIM?

    1. Hello, Thank you for your encouraging comments. Sorry for the delay in replying it's been a busy few weeks.

      What your touching on is a very interesting area which is hotly debated at the moment. The best way to approach this subject I feel will be to dedicate an article to it as there are quite a bit of details to cover. IFC data formats are in essence a 'open' and neutral data format which set a data standard which if used can assist the 'interoperability' between software packages. For instance REVIT can export all of the information and modal data from REVIT in an IFC data format which can then be imported into various other software packages, beyond the Autodesk circle of software.

      As I say there is a lot to this subject so I will happily attempt to cover it deeper in an article in the near future


Please feel free to comment, I will read all comments and topics for discussion.