BIM and what it means for clients…

I’ve been thinking about this post for a while and thought it might be of benefit to others giving an outline of how I work and my thoughts about BIM

This post is written to give clients a better understanding of the architects process but will also be of benefit to other architects and related design professionals.

But first, what exactly is BIM?

To give a understanding of BIM we need to firstly to give a little ‘back history’ on the production of architectural drawings…


The first major jump from traditional hand drawings was two dimensional Computer Aided Design where the ink lines and text were replaced by digital, 2 dimensional versions. This change in drawing production gave a quantum leap in the efficiency in the speed in architects offices; probably not in the actual speed at which the drawings are produced (which in my opinion was often the same), but instead the speed increase came when drawings were edited and deleted without having to use razor blades to scratch the ink from tracing paper.


The next jump in Computer Aided Design was the transition from 2D to 3D; where the two dimensional vectors are replaced with three dimensional equivalents. Working in three dimensions gives massive benefits in terms of aiding the design process and huge presentation benefits when showing the virtual model of a building to clients, planners and the like.


The next smaller jump from 3D CAD was where the three dimensional elements are replaced by parametric equivalents where a door has the characteristics of a real door such as the height, width, leaf, frame etc… rather than just a collection of 3D vectors that looks like a door. The concept of parametrics is that the object of this type can be amended through a simple dialog box rather than through complex 3 dimensional editing. As well as having 3 dimensional data, a parametric object can have numeric data such as cost, colour, finish etc… which enables the production of a set of schedules or cost reports.

An extended vesion of using the a 3D model is that you are now able to extract the 2 dimensional drawings for planning applications and construction drawings from the same 3D model.


The next logical and current conclusion is that the 3 dimensional model is used collaboratively between all members of the design team; the same 3D model is exchanged between the architect, structural engineer, mechanical and electrical engineer so that any conflict between architecture and other services is spotted at an early stage.

So which one do I use? The answer is all of them and it depends upon the type and scale of project for which is the most suitable.

If I need to draw up something quickly in 2D and I know that any changes are highly unlikely then I’ll just use 2D:

2D sample drawing

2D sample drawing

Most of the time however is that I’m using 3D (combined with parametric objects) so that I am designing in 3D, presenting 3D models and drawings to clients and planners and then using the same 3D model to extract the 2 dimensional drawings required during the planning and construction stages:

The YouTube movie below shows a rendered 3D Model where all of the planning drawings (shown under) were taken from the 3D model; what’s particularly interesting is that I can see potential clashes that would have been harder to detect without the 3 dimensional model (where the brise soleil meets a concrete barge is one instance):

2D drawing from 3D model

2D drawing from 3D model

I am also able to exchange data with other design professionals; the current BIM standard is IFC format – I will say however that the type of work I undertake (which can be highly crafted buildings) I feel don’t all neatly into this BIM/IFC format and the type of projects ideally would be on a larger and more standardised (I may be proved wrong however as I’m currently testing a series of projects to see how suitable a BIM type approach will be. I therefore still do quite a lot of work in 2D, predominantly on the details and dimensions/annotations; although the core bulk of work has been taken from the 3D model:

Vectorworks sample

Sample of Vectorworks construction/tender drawing

Sample BIM Export

Sample BIM Export

So what does this mean for clients? Basically that I have the capability of providing architectural services at a every level of scale and detail; from small projects to large schemes and have the infrastructure and implementation to work in 2D and 3D and also to exchange information on larger schemes using BIM standards with other design professionals.

Images from the CAD software I use (Vectorworks), 2D, 3D, Parametric design and BIM.

These thoughts and opinions are entirely my own and if you think I’ve got anything unclear or incorrect then please let me know…

9 thoughts on “BIM and what it means for clients…

  1. Nice description of the progression from hand-drawn to 2D to 3D and BIM. It is probably worth adding that BIM also adds other dimensions. First, the model can be used to model how the building will be constructed (time, so 4D), and you can also associate cost information, energy use, carbon, etc. As a result, some commentators describe it as nD.

    And it is not just about collaboration during the design and construction. Major clients are also looking at BIM as a way of capturing information from FM, operation and maintenance, so that their future projects are informed by real-life performance data from their existing built assets.

  2. Thanks for this post Mark. It is good to see matters that can be complex distilled into more readable English for lay people to understand.
    For your clients I can imagine that the use of appropriate tools can offer good savings in redesign and alteration costs, whether with a small domestic project, or a larger, long term one where whole life costs are a consideration.

  3. Really good post Mark that explains where we have got to with BIM right now. I’ve just been viewing the NBS BIM roundtable discussion that Su Butcher posted the link to on twitter, and it certainly is the future for the industry. I’ve also heard that the other dimension is 5D being the cost aspect too.

  4. May I ask for a little more back story Mark? I’ve most recently used Microstation mostly as a 2D program (with Sketchup as 3D), quite happily, but moving to a Mac, I’m looking at the alternatives available. My understanding from using VW several years ago was that it was really a 2D program with limited 3D capability, and some time in the last few years has developed to something that barely resembles what I used to use.

    Did you ever use VW as a 2D program, or did you jump straight into 3D & BIM? The reason I ask is because I suspect it’s easier to start as you mean to go on – I’d imagine you need to unlearn some bad habits if you’ve used it as a 2D program first.

    The other question is how easy is it to generate clear 2D drawings from the model? I found that in Microstation a lot of work was required to make the sections look ok. Do you need to draw over the generated drawings?

    Great post by the way,


    1. Hi Jan

      Did you read the potted CAD history at:

      In answer to question:

      In the beginning… (sounds biblical), VectorWorks was once called MiniCAD and was predominantly 2D although you could do some great 3D stuff with it. I tended (then) to draw in in 2D and if anything needed to be done in 3D, work that bit up separately.

      Nowadays however the power in the 3D means that (you could) work in 3D all the time and taake the 2D drawings from the 3D model. I tend to do this for the sketch, design and planning application stages. The drawings at this stage are fine, I add a little 2D detail but most of the info comes straight from the 3D model. The detailed design and construction drawings are based on the 3D model but I tend to do a lot of the detailing in 2D using the 3D model drawings as a starting point. This tends to happen as most of the structural engineers I work with are 2D only.

      I’m sure there are others that will be adding every beam, nut and bolt into the 3D model (which you could do) and then take the construction drawings from this; I personally don’t work this way but I’m sure there would be some that do.

      Hope this helps


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