Sunday, January 24, 2021



Let’s try to cobble these LinkedIn posts into a blog.

I’m enjoying a new process of several short posts over a weekend, as I work.  But it would be nice to keep a more permanent record going on the blog here.  It started on Thursday evening with the decision to take a crack at an Art Nouveau door by Victor Horta.

The interesting aspect of this is how to maintain some parametric resizing ability with these irregular shapes. Weekend preview.

I love the Art Nouveau elements! One of my favorite periods for both Art and Architecture! Yes I fell for Art Nouveau as a teenager in the 1960s. Part of the "Art is Rebellion" metaphor I guess. 🙄



Tricks of the trade in a BIM context. To stop these delicate quirks /flourishes in the corner of door frame and opening from distorting as you flex the door size... It's possible to create reference planes while in "sketch mode" and to tie them to the edges with locked dimensions.



This part is quite tricky. I can keep the arc tangential to the bottom edge by locking it to the centre line of the door panel. But as I vary the door width the spline twists. Really I would like it to always meet the side edge at right angles... more or less. I love these challenges and what I learn along the way. About #doors, architectural history, #joinery #geometry ... #revit

Life is good people

Thanks for posting..... it's always fascinating to see your experimentation and great that you share your knowledge

My Pleasure. Wouldn't be half as much fun without the sharing bit 😁

you're using a spline. Have you thought instead of spline to try with two arches that you can control?

I'm using splines for their automatic scaling when you lock the two ends. Works very well for the curvy transom, not quite so well for the quirk, but it will do for now. Thanks for the suggestion.


Hotel Max Hallet, 1902. Just a quick #bimpencil sketch this afternoon. Building the house around the door 🙄 May get a bit further tomorrow. Thanks to those who posted comments and suggestions, all useful to be sure.



It started with a door, but these #bimpencil adventures always lead to unexpected pleasures. Three glass pods balancing on steel prosthetics like pirates' legs lured me into some careful setting out this morning, and to add an "arch flattening" parameter to my half-round opening family so that it can double up as elliptical. More steel peg-legs next to support those arches. Fascinating stuff to be sure, to be sure, (Jim lad.)

... and to my shame I had never heard of Victor Horta; as ever, thanks for the invaluable back-handed (unintentional !) education I am receiving from you (all) 🥂

Interesting modelling. Would be nice to see the original windows to compare

Hotel Hallet by Victor Horta. Lots of photos online for this and his other houses in Brussels.

good luck with the curved top of the curved windows. You are not modelling with curtain walling system of Revit, right?

I have been using a curtain wall to rough this out and towards the end of the day made a loadable family for the top portion. Will share more tomorrow. It would be possible to spend some weeks modelling this house so I am being quite selective about how far I take any one family. The aim is to understand the rationale behind the design



They look a bit wierd from the outside, but nice curved window seats overlooking the garden. The top lit stair hall is typical Horta.

Excellent. i like the basement being on garden gf as well. but keep in mind function unless the 3 windows are each used desperately( piano, office desk and seating in the middle) y not make the middle one larger (maybe oval maybe just a striated really big bay window).

Thanks for your comments. This is a study of an existing historic building from 1902 in Brussels by the originator of the Art Nouveau style, Baron Victor Horta.

Love the window seat feature !

Certainly a labour of love and a search for deeper understanding of the way our species has built containers to inhabit in different times and places. I have a passion for history, for learning by doing, for geometry too, I guess. I have a deep interest in the building trades stretching back some 50 years and have been messing with computers for more than 35. Sometimes call myself a BIM addict 🙄



Just a rough BIM sketch, but a fantastic learning experience for me. Try to imagine being a Brussels lawyer in 1902 and commissioning this chic, state-of-the-art townhouse from the famous Victor Horta, pioneer of Art Nouveau. 50 years later I was just one year old. 70 years after that will take us to next year. Will I take this further? Does anyone else want to take a couple of door/window families and run with them? Stay tuned folks



There was an interesting exchange with Mark Maas who I already knew a little from the Notre Dame work. 

Why won’t you work with profile families?

Profile families are great Mark. Not sure how they would help in this case. Maybe your question is why don't I assemble my more regular framed door panels as a series of sweeps? Not sure I have a good answer to that. Perhaps I will give it a serious shot one of these days and assess the pros and cons. I have always used loaded profiles for the architraves (trim) and often for the door frames, but not so much for the construction of door panels.

the purple lines good be you’re profile family. I think profile families are more stable and have more possibilities to flex dimensions. And you can easily exchange them within the host family.

On reflection I think Mark’s proposal of using a loaded profile for the glazing cutout in the door has a lot going for it.  Definitely want to try this out in a future study.  One further bonus is that you can use the same profile for the glass as for the hole it fits into.

Friday, January 8, 2021



Hello 2021.  Catching up on work I did in mid-December.  Starting with a quote from my “LIVE” LinkedIn posts at the time.

"Assembling reference material in preparation for a model of Taylor's wall. Only need to tackle one half, given the symmetry of the two wings. Looking forward to a productive weekend on the ..." 

Bank of England / BIM360 / way-we-build # # #


Taylor built two new wings, one to the East and later on its symmetrical twin, creating a grand Palace front facing Threadneedle Street and spanning the entire city block from Princes St to Bartholomew Way.  Quite a stroke of luck, (by the way) that Sampson’s Bank was so well placed at the centre of a city block. 

The original Bartholomew Way was not at right angles to Threadneedle Street, but Taylor squared the corner up.  As a result widens considerably from South to North even today.  The SE extension came first, with four Transfer Offices to deal with the rapidly expanding market in War-loan shares issued by the Bank.

I need a column.  Start with the closest standard item from my modular library. This is a double-nested planting category RFA to allow scaling.  Open it in family editor, select the nested “INNER” and open that.  Three parts here (Base Shaft Capital)  Don’t mess with the capital unless you have to, rather complex.  The base needs to be plainer and the proportions generally taller and thinner.  So delete the void cuts on the plinth reduce the profiles of the sweeps, stretch the plinth up.  Open the shaft and stretch that up.  Now it will overlap the capital so that needs to be moved up to compensate.  So in 15 or 20 minutes I have the column I need (round fluted Corinthian with a plinth) 

The ability to have half or ¾ columns is built in to my system.  Half columns can wrap the corner with an instance tick-box but that’s not needed in this case.


So what about the spacing.  Is it completely regular?  I don’t think so.  Seems to me he had to tighten things up a little around the corner.  I do some studies with dimensioned drafting lines to come up with a spacing that works for me.  This is complicated by the position of the central door.  In reality the East wing was out of square in all kinds of minor ways.  This is not reflected in my model (A) because we don’t have reliable information, and (B) because it would be an absolute pain to force Revit to place walls at fractions of a degree, and (C) because dimensioning would also be a nightmare.

But the knock on effect is that the centre of the doorway on Bartholomew Way is probably a couple of feet further to the North than it should be.  These small discrepancies build up.  So I varied the spacing either side of the door and you don’t really pick it up.  Our eye-brain system is so used to assuming symmetry from minimal cues that our subconscious does the necessary.


Another direct quote from my LinkedIn live posts

"First mock up of Taylor's screen walls, framing Sampson's Bank of England like two bookends. It's not going to be fully symmetrical in practice. More on that over the weekend, (which starts tonight :)"

I do like the upper part of this image with most of the context unloaded.  You get a really good feel for how close the bank is to Grocer’s hall, and to the way that Taylor extended Sampson’s composition from a substantial town house, to a grand palace.  Shades of Palladio here, although his side wings were farmhouse barns.  Could there be an interesting metaphor here?  Bank of England as gentleman farmer.  Interestingly enough, several of the Bank’s directors did buy up properties in East Anglia and build themselves country homes to signal their arrival amid the landed classes.  Like the Veneto, this is relatively flat countryside with a network of drainage ditches and canals.


The corners are reinforced by doubling up the columns (free-standing columns in front of the normal engaged columns) Above this projection, a triangular pediment.  I roughed this out “in-place” to get the proportions right, then copy-pasted the geometry (while in Edit mode) to an external family template.  This gives me a stable object to place multiple times, plus an easier environment in which to tweak the mouldings and add further detail. 

The large arched recesses alternate with smaller niches which use a revolve for the void cut instead of the extrusion.  Later I will add keystones and other small embellishments to complete the effect.


Taylor's wall was removed by Soane, late on in his career, finally imposing his style on the entire perimeter of the Bank. In its turn, Soane's wall was completely rebuilt by Baker but with many similarities.  One of my first puzzles when I started on Project Soane more than 5 years ago was to try to understand the differences between the current screen wall, which I had photographed in some detail, and Soane’s phased work, for which there were a number of drawings, some of them conflicting, and no clear indication of what was actually built.  To complicate the issue, the photographs that exist date from at least 50 years after Soane’s death by which time the parapet had been butchered, railings added, plus who knows what Many layers of dirt and grime to be sure.

I digress.  I have a file called “row planting” that dates back to 2013 or so.  Combining the Planting category hack for scaling with linear arrays to do things like egg & dart or modillions, but also balustrades.  Do I dipped into this to create a wall-hosted family with variable length panels.  Another quick fix with unlimited future potential.  Modular once more, in that you can swap out different balusters at will, scale up the height as needed, vary the spacing.  By accident I had the link for Soane’s entrance block loaded on top of Sampson’s version.  Makes for an interesting comparison.  This building has changed so many times over the years.  Fascinating story.  I’ve been learning something new almost every weekend for more than 5 years now.

Linked In again

“Progress on Taylor's screen wall. Wall-hosted balustrade with parameter driven lengths/number of balusters. Smaller niches to alternate with the large arched recesses. By happy accident, Soane's remodeling of the entrance block superimposed (in blue) over Sampson's original.”




OK, so I had two L-shaped screen walls to contain Taylor’s two wings along Threadneedle Street, which was fine for a first order of approximation.  But in reality the return leg on the West side needed to be slightly longer than the East side along Bartholomew Way. 



Also, while the first extension called for a separate Entrance to the Transfer Halls (to help separate the speculative trading activities from the sober atmosphere of the Pay Hall and the Bank of England proper) The Garden Court needed to be a more secluded zone, similar to the private garden that the Director’s Parlours had overlooked when they rented the Grocer’s Hall.

I separated out the return legs, and ultimately had three links.  Two instances of the front portion (A).  One on the East, then a mirrored copy on the West.  The East wall with its central doorway becomes a separate linked file (B).  A modified copy of this becomes the West side, down Princes Street (C).  It seems that Taylor gave this wall a simpler treatment, Princes Street being more of a backwater perhaps, but mainly because this is not an entrance façade.


So I now have the exterior of the Bank quite well developed, as it was when Soane arrived on the scene.  We already had this area as it was when he retired as part of the work I did for the Project Soane competition (and beyond).  The next big “missing piece” will be the Transfer Halls, as built by Taylor.  These can then swap out with the Soane versions of those spaces as we continue to build up our timeline. 

The next post will be about the timeline itself. i.e further development of the schematic model I have been using to understand the way the building evolved, which is quite complex.  But for now let’s just enjoy the main frontage as created by the first two architects (Sampson & Taylor) over a 50 year period


Thursday, December 31, 2020


 More reminiscing. This is a continuation of a thread from mid October.

In 2013, one of our lead designers at GAJ was a Spanish architect called Ignacio.  He was responsible for my spiky geometry explorations.  His team were all Sketchup guys, but we often talked about how to capture the geometries he was exploring within a Revit environment.  One of these projects was a diagrid flowing over a “rolling hillside” form.

I learnt quite a bit more about divided surfaces and complex geometry.


Furniture.  These days I am often involved with bringing the Interior Design component of a project into Revit.  Usually my role is content development and designing “BIM processes” ... schedules, data, specification codes.

I have quite an interesting collection of furniture content, acquired over the years.  One file is devoted to designs by Fritz Hansen.  The approach to generating the required geometry is quite varied.  Sometimes it’s best to download a mesh from their website and combine this with symbolic lines and masking regions in orthographic views. (Some people reject this approach) Sometimes native Revit geometry does a good job.  Sometimes you need to be a bit more creative with the Revit geometry tools.

These days I usually use very low-res geometry for the 3d views, and a CAD-like representation in Plan.  The visualisation and detailed spec is handled by a non-BIM team.  We just need a recognisable object which cross-references the specification code.  It’s less than ideal in my view, but that’s the current state of play in my office.


I was exploring “the space of possible rigs” following on from the success I felt I had with my “scalable rectangular rig.”  Presumably the simplest type of rig would be a straight line.  What can you do with that?



The rectangular rig is amenable to expressing the graph of an equation, could be a quadratic, for example.  I explored this idea to create a general family of forms, of which one particular instance would be the Gherkin by Foster Associates. This is based on work I did for one of my presentations at the Revit Technology Conference in Auckland a few weeks earlier. 

I’d like to paraphrase the last sentence of this post here.

“If you are interested in the History of how buildings work, then a tool like Revit is an amazing aid to research”

Seven years later we have developed that idea much further with our work on Project Soane and of course the Notre Dame model.  Open-source, collaborative research into our built history.


There follows a series of posts that take the scaling properties of the Planting category, and nest it into system families like Curtain Walls.  The first one is based on a common sand-cement “brise soleil” block.  How useful is it to make this infinitely scalable?  That’s a moot point, given that these things usually come in a couple of standard sizes. 

Maybe if you were designing screens made from cast aluminium panels.  Depending on the quantities you might be OK with a custom mould for the project.  So at design stage, the ability to easily vary the scale of the pattern might be useful.




The next post takes the scalable, decorative curtain panel concept a bit further.  At least it imagines further examples of designs which might benefit from this approach.

“I'm backing the double-nested technique for situations where you want to play around with the size on the fly, experiment with design ideas quickly.”


Back to classical architecture for the final post in this series.  Stone balustrades, carved mouldings, standard designs like egg & dart.  Can the scaling properties of double-nested planting help out here?  I made quite good progress with this here.  And since then I have developed these families a bit further.  In the comments Paul Aubin raises an interesting point.  How do you do this around a curve?


One answer I explored later was to use a railing.  It’s not very nice to have carved stone enrichments, (or maybe plaster cornices) in the Railings category.  If only we could assign a railing to a couple of other categories.  Maybe Wall Sweep, or even Generic Model.  I’ve no idea how realistic it would be to do this within the Revit core code, but it’s the kind of thing that I think would be useful.  One of the annoying “restrictions” we would like to remove, to paraphrase a recent post by Tim Waldock.