Tuesday, September 16, 2014


This is a talk I gave this morning at the second Dubai "BIM Breakfast"

Why have I chosen to paraphrase Bill Clinton's election slogan for my title ?  BIM is a propaganda war.  We are fighting for the hearts & minds of the construction industry.  Trying to drag it out of the stone age.

Most of us have heard the phrase "it's all about the I in BIM".  But stuffing your model full of data doesn't guarantee a well designed building.  So for me "It's all about the DM in BIM" ... and I don't mean Dubai Municipality ... I'm talking about Decision Making.  That's the focus of this presentation.  How can better BIM support Decision Making processes ... with a special emphasis on the role of manufacturers, suppliers & specialist sub-contractors.

When I was a young boy, sometimes I would go shopping with my mum.  We'd walk down to the butcher's & buy some meat; across the road to Uncle Sandy, the baker & buy a fresh white loaf; then back along the street to the greengrocer ... Each of these shopkeepers knew us by name. "Hello Mrs Milburn, what will it be today ?" Everything would be placed carefully in brown paper bags and there would be a hand written receipt, added up the old-fashioned way.

Today I drive to Spinneys, Lulu or Carrefour & rush up and down the aisles with my trolley, grabbing pre-packaged merchandise as I pass.  At the checkout, someone I never saw before scans the bar codes.

At this point, information ripples outwards across the universe at the speed of light, updating databases in real time.  Every day, that branch knows exactly what has been purchased. They can pull up graphs of purchasing trends over the past month, or the past year.  Down the supply chain, the guys who make baked beans or breakfast cereals can aggregate data from thousands of outlets.  In board rooms around the world this information is converted into glossy reports that inform decisions about where and when the next mega-mall or factory will be built.

In my lifetime a digital revolution has completely transformed the retail industry.
But it seems that the construction industry has not changed to the same extent.  Why is this ?  Part of the answer is volume, rapid turnover.  Every day, thousands of cans of Baked Beans are sold, millions perhaps. Retailing is a repetitive process that is relatively easy to mechanize, digitize, optimize.

At Godwin Austen Johnson we design a lot of hotels and resorts.  Our projects are well known and our reputation is high.  But when I say a lot of hotels, I'm actually talking about a handful each year, and every one of them is substantially different.  Some are city-centre business hotels, some are coastal resorts, some are inland desert villages.  The repetition factor is negligible.

The role of information in construction & retail is very different.  Take for example the ratio of DATA to DECISION MAKING.  In retail you have a lot of highly organised data, and relatively few decisions.  You might adjust your shelving arrangements twice a year for example.  In design and construction our data is all over the place and we are making dozens of critical decisions every day.


This is where BIM comes in.  A BIM authoring tool like Revit is actually database software.  Retailing has transformed itself by linking all the points of sale to databases and then connecting these databases together.  We need to connect our BIM databases to the rest of the supply chain.  But first let's take a closer look at BIM authoring, for the benefit of those who may not be hands-on modellers, which is to say, the majority of the people in the construction industry.

05 Rural House video (maybe I'll get around to uploading this later- it's a very simple introduction to BIM authoring)

This short video click illustrates in a very simple way how a BIM authoring programme like Revit is a database application.  All the information about this small Rural African House is stored in a highly systematic manner.  The definitions of all the components are stored in a list organised by category: wall, roof, window, door etc.  Each of these components is made from materials which are cross-referenced from another list. 

Every piece of information required to define the building has its own place in the database. Change any one of these parameters and the effects will ripple through the entire model.  Furthermore we can sort and filter this information in many different ways to help us analyse the current status of the design and to identify areas where decisions need to be made.
So where do the suppliers and manufacturers figure in all this ?

You can download manufacturer content (BIM objects) from a variety of web sites. Quality varies and there are big gaps in some areas, but the message is spreading and huge strides have been made over the last 2 years or so.

The question remains though: is this really what BIM is about?  Do we really design buildings by dragging and dropping objects into our projects ? 

Isn't the essence of design teamwork, brainstorming, sharing ideas and knowledge, sitting around a table and solving problems.  Shouldn't we be looking for software that supports interactive processes ?  Actually quite a few manufacturers have been thinking along these lines for some time, just not in the context of BIM.

German sanitaryware manufacturers Duravit have an on-line application that works almost like BIM.  You can create a bathroom of more-or-less any size and shape, add doors and windows from a visual menu and then choose Duravit fittings to complete the bathroom design.

UK company Ideal Standard have a similar system which goes even further.  The images feature photo-real textures and once you are done the app will generate a schedule with product images, part numbers, quantities etc.  They also offer specification tools for architects and CAD downloads, but no BIM objects.

There is a huge "disconnect" between the user-friendly, interactive design apps and the cumbersome download packages that many manufacturers provide.  Hit the download button for one of the Ideal Standard ranges and you get a zip file with dozens of folders.  Inside each folder is a huge list of CAD files with indigestible names. 

Rubber flooring specialists Nora have a nice app on their web site that allows you to choose from a number of typical context images (schools, hospitals, factories etc)  Choose any product from their range and you get a convincing image of how a finished project will look.  They also offer BIM downloads: pre-formated material swatches that include embedded data and images that allow rendering from within the BIM application.

Sadly there is no connection between the material selection app and the BIM downloads.  In fact the BIM materials are far from user friendly: huge download sizes and difficult to follow instructions that actually don't work.  What would be really cool would be if you could select materials via the app, add them to a shopping basket, then download a zip file with just those materials (high res context images, data sheets & BIM data, all in one package plus a web link that you could email to a QS or a contractor so that they could access the same data and hold their own conversations with Nora)
None of this should be taken as a criticism of the companies concerned.  I chose these 3 because they make good products and they are making a real effort to create interactive digital tools.  I give them top marks for pushing the envelope.  What remains is to make their tools talk to our tools.  And that is a task for all of us.

Part of the answer may be an app developed by a web site called "The Source" who offer a portal to "Global Product Data"  (Global is of course a well known euphemism for American)  Actually the app is really neat, I just wish it would link to manufacturers we use in the UAE.  Give it time, give it time.

At this point I'm going to invent a new acronym "Cloco Zones".  It stands for Cloud Collaboration: Web Portals where Building Designers can meet up with Manufacturers and Suppliers within a BIM environment.  Imagine a hybrid between BIM 360, the Ideal Standard bathroom design app and GPD ProductTAG.

Cloud Services like BIM 360 Glue are already offering interactive zones where Consultants, Contractors & Clients can engage in digitally informed problem solving.  Wouldn't it be great if we could extend this into the world of technical advice and support that we have been receiving from specialist suppliers and subcontractors for decades via more traditionally means ?

Take ironmongery for example (door hardware).  The traditional method is to send an email out to a friendly supplier, give them floor plans (with door tags) and a schedule of door types, then wait for a couple of weeks while they set to work on analysing this data, feeding it into excel perhaps, & creating hardware sets.  Eventually they send us a pdf, or maybe even a word document or excel file, with little pictures, product descriptions and quantities. 
Checking this through and pushing the data back into our model consumes more time and by then there have probably been one or two design changes, so we end up sending comments on the first submission along with revised drawings so that they can update their schedules.  The whole process can easily take a month or more.
But what if we sent a subset of the BIM data through to a web portal, which they could populate with their proposals. 

Firstly this would give them a much better 3 dimensional grasp of the project, and being a database they could sort and filter the information in any number of ways.  Built-in markup and messaging capabilities would allow rapid exchange of queries and suggestions.  Surely this would result in better decisions and faster turnaround times.

Better still, the same web portal could be used at tender stage to inform the price negotiations between suppliers and contractors.  A lot of manual cross-checking and duplication of effort could be avoided, and of course once the project is awarded, the data can be passed seamlessly through to the procurement process.  I know that standards and software compatibility are going to be big issues, but surely this has to be the future.
So to conclude, here is my definition of BIM.  Two definitions actually

In other words, BIM is much more than Revit, or any other authoring software.  It is the use of digital tools to inform our decision making processes so that we can design and construct buildings more effectively.

Consultants have digital tools, Contractors have digital tools, Suppliers have digital tools.  Better decision making requires that we teach these tools how to talk to each other.  This in turn will allow the human beings involved to have better-informed discussions, and put their skill and experience to use

That's my message for today.  I will be posting this presentation on my blog later in the week. Lots of other stuff there if you are interested.  Also GAJ web-site is well worth a look.  We've been using BIM for more than 8 years now.  Good design, good processes, always learning new stuff, not afraid of the future.

Monday, September 8, 2014


Continuing with the theme of Rigs for lofting profiles in Point World, this is what I call the "Freehand Spline" rig.  It's freehand in the sense that not everything is subject to dialogue box control.  To make some kinds of changes you have to open up the family and manipulate it directly.

I grew up with freehand drawing, so I have no problem with that.  Parametric dialogues are great in their place, but there is still a lot to be said for the direct, intuitive approach.  Witness the success of finger poking devices in recent years.

I wanted to represent a type of chair that is very common.  It might be bent plywood, or it might be moulded plastic, or it might be something softer.

You could make a reasonable go at it in Vanilla using a sweep tapered off at the ends with void cuts.  I've chosen to do it in Point World which offers a slightly more elegant solution and allows more subtle variation to the shape.  The profile I used for my first example can be varied in both width & curvature.

So the chair is more curved in the middle where you sit, and rather flatter at the ends.  This is most evident in a side-on close-up.

I experimented with a few different profiles.  Most of the complex profiles refused to "create form" but eventually I found one that gives an upholstered cushion effect, based on a 3d spline and a straight line.

This varies quite nicely based on a single width parameter.

The irony is, that the most elegant form to acrue from these experiments is based on a rectangular profile and could surely be made quite convincingly in vanilla.
The base is lifted straight from the space chair that I featured a couple of weeks back.

So what are the advantages of Point World in this particular case ?

First of all there is the ability to modify the spline directly and get immediate feedback on the resulting shape.  In Vanilla you would have to "edit sweep", "sketch path" make the changes, "finish path" & "finish sweep"

Secondly you avoid the need for at least one void cut to taper the back of the chair (two if you want to taper the seat slightly also)  Apart from appearing rather clumsy when selected in family editor, these cuts inevitably leave small seams on the edge of the seat.

So for the sake of experimental completeness I decided to make 3 versions of this chair.  The first is based on the adaptive template. It's the first one I showed.  The second is pure vanilla, with void cuts, as above.  The third is vanilla, but the seat is taken from point world version, exported to SAT, reimported and exploded.

The adaptive version can be opened up in family editor and the shape adjusted using Point World techniques. On the down side it behaves strangely.  It will not respond to the level & offset parameters in the properties dialogue.  When you press space-bar, instead of rotating 90 it jumps several metres to one side.  On subsequent presses it swings around in a cirle, returning to base on the fourth press.  You can avoid this be making it as a mass family, then you just have the "wrong category" problem.

The pure vanilla version works fine, but I find it hard to love those orange voids that jump into life whenever you touch any geometry.  "Crude but effective" seems apt.

I thought it might be fun to round the edges off using "pick-edges" mode for a void sweep.  Would have been exciting if it worked, but it didn't.  You can round off one side at a time, but this leaves an awkward little gap at the end.  Also attempting to add the next side yields one of those "circular chaing of references" errors.

It is possible to add a bullnose edging using "pick-edges" but no use trying to "join geometry" to hide the joint line. Destined to fail.

My next brainwave was a thicker rectangle with an edging that mimics upholstery. This worked fine.

So why not make the seat less flat, thinks I.  Turns out that a double hump refused to loft itself along a spline.  One node too many.

The lop-sided nature of the "4 node" curve is a little odd perhaps, but beggars can't be choosers.

It turns out that you can delete the seat and the edging remains intact, which is just as well because the new geometry won't take a "pick=edge" sweep.  You can copy-paste between families to drop a curvy seat into a straight edging.

The difference is extremely subtle, even when you exaggerate the curve. The eye is fooled by the straightness of the edge I think.  Using a patterned material makes the curvature more obvious, but is it really worth it ?  I'm not sure, but I'm determined to keep trying to generate furniture families with a softer look.

It seems that the edging is the most expensive piece in this family. File size more than doubles.  So I tried ditching the edging and cutting off the ends with a curved void.

I went on to experiment with 2 solids hosted on the same spline. Also attempted to reduce the "flat end" effect by grading the profile size down in a series of countours.

And that's the end of my freehand wanderings.  Nothing very dramatic in terms of end results, but an interesting technique all the same.

Sunday, August 31, 2014


This is another one from RTC Chicago.  It's based on a picture of a chinese pot that I decided would be an interesting shape to model in Point World.

Once again we are lofting with loaded profile families, and the rig is a combination of "straight line" & "rectangle".

So we start with an octagon profile. There are different ways to set about this.  You can base it on points, 8 of them all spaced out equally from the centre with a parameter to control that distance.  Or you can dispense with the points and dimension directly to the lines.

Turn this into a scalable profile with a simple formula.  R = input * Scale. ( I use R for consistency, because the simplest profile of all is a circle, radius R)

So we have a mass profile.  Load this into another mass family.  Draw a vertical reference line at the origin point. Host points on that line.  Reveal the normal reference planes.  Host instances of the profile on each of these, then play around with the input values so as to build up the shape of the chinese pot.

You need to select the profiles in groups and create form.  First 4 profiles, then 2, then 2 again, then 4 again.  Sometimes two forms share the same profile.  By the way I forgot to mention the height parameter.  And of course the profiles and the height are all linked to the same global scale factor.

At the top of the pot, there is a little pointed knob for lifting the lid off.  This is a revolve.  We could use a series of circular profiles, but I'm opting to illustrate a different technique.  Typically, the rectangular rig takes the form of a ladder.  So I'm building one of these off the top portion of the vertical line.  It involves hosting points on points and giving them an offset.

Create a loop using splines with 3d snapping.  Select this and the vertical line to create form.  Revit should interpret this as a revolve.

You can see that the 3 instances shown above vary in both height and slenderness.  Quite easy to set up. The scale parameter (used to control the nested profiles) is calculated from height & slenderness via a simple formula.

That's as far as I went for RTC, just a quick example in passing.  But of course we can take this further by loading different profiles.  The possibilities are endless, but here are a few.

One way to achieve this is via type-based profiles. This involves a bit of heavy lifting, with 9 different types needed for each profile.  The amount of work can be reduced somewhat if you base the new profile on a copy of the old one.  That way you don't have to set up all the named types again.

I followed this through to create a family with three types (octagon, circle & square) plus instance parameters to vary height and slenderness.

To get more value from my effort, I "saved as" 3 times and played around with the positions of the profiles and the relative size of the knob.  The result is a systematic exploration of variations in shape.  I'm not sure why anyone would want to have so many different pots to choose from, but just in case you do, this is one way to achieve that end.

Another approach, would be to use instance based profiles.  That's how my original pot was built because it's much faster to set up that way.  But when you swap out the profiles with a parameter all those instance values get lost and you end up with a shapeless extrusion.

Not to worry, you can just create another family for each shape.  Even better, rename the profile in the new family to match the name of the profile you want to load.

I followed this approach to create families based on profiles incorporating my famous "bulge factor" parameter.  This dates back to my Doric Pumpkin experiments and uses a points-based profile.

The "bulge factor" will take you all the way from very concave to very convex.  I didn't do "very concave" in this example because it doesn't look right in a pot.

The nice thing about this kind of exercise is the way it reverses the diminishing returns principle.  Once you've done the initial work, adding a new profile takes very little effort.  Also varying the relative heights of the different sections is easy and before you know it you have dozens, if not hundreds of variations.

So just remember, these families belong to the mass category.  Other than that, they behave nicely.  If you want to play with them, follow the download link.