UP ON THE ROOF WITH MR SOANE

This is a bit of detective work that I did while modelling the lanterns of Soane's banking halls at the Bank of England.  There is an old photo that claims to be the lantern to the Old Shutting Room and I thought it might be interesting to recreate it with a camera shot in Revit.

I was interested to know what the other lantern was, behind and to the left.  The church spire is clearly St Margaret Lothbury, which I photographed on my recent visit.  One of Wren's many City churches I believe. 

I tried to line this up with a candidate space for a dome/lantern, but the nearest fit I could find is the Power of Attorney Office, represented here by an orange pole.  The problem is that this is a semi-circular space.  Doesn't look right to me.

Even worse, when I slotted in Russell's CTO as a link, its lantern popped up into view to the right.  Definitely not matching the photograph.

 

So then I followed a hunch and took a shot from behind the Stock Office, looking past the CTO towards the spire.  Near perfect match.  What is more if you peer through the dirty glass in the photo you can see the arched window of the CTO, and even more telling, the steel brackets of the Stock Office lantern. That's clear enough for me.  Wrongly labelled photograph, it happens.

If I am right then we have a photo of the exterior of the CTO lantern.  From the interior shot of the same age this appears to be glazed.  Is that dirty glass that we can see?  I think it must be.  The Stock Office on the other hand is clearly covered in sheet metal.  And we know that it had a plastered ceiling, from the photographs and from the reconstructed version.

 

By the way, the pitched roof in the background is the Consols Library, which is the orange roof in the foreground of the next picture.
 

This really is a fascinating roofscape.  I definitely haven't unlocked  all its secrets yet, but the pieces are starting to fall into place and it's much more interesting than I had imagined.  You can see why he was keen to impose order to the whole complex with his exterior screen wall.  It really is quite a hodge-podge, and I haven't even started adding the chimneys which you can see in the photograph and deduce from the many fireplaces in the drawings and interior shots.  Of course they had coal fires, all the buildings did, hence the famous London Smog.

I'll leave you with this thought.  The Bank of England is starting to remind me of a box of toys.  When my kids were young we had these large drawers on wheels that went under their beds.  Just gather all the toys up from the floor and wheel them away for the night.  Soane created this cool, suave, exterior screen, a neat and tidy box to contain the chaotic collection of toys that the bank had generated to house its activities over a century or so of piecemeal growth. 

Weekend beckons, let's see what I can come up with :)
 

JOHN SOANE & CANOPY DOMES

There's a half-finished post about my work on Project Soane from a couple of weeks ago that I may come back to, but for now let me skip ahead to what I've been working on this weekend.

I've been getting to grips with the interior layout of the Bank of England.  Just broad brush stuff: what was there when Soane was first appointed and how he renovated and expanded it over a period of 40 years or so. 

Then I started to home in on the series of banking halls around the Rotunda that he renovated in two major phases.  This work is partly informed by some old photos taken by Frank Yerbury shortly before most of the bank was demolished to make way for the current version.  These were on a DVD that I bought at the Bank Museum in early August.  Some of these spaces go by different names based on evolving usage.  I am using the names on these old photos which I find relatively easy to remember.

The photos are very useful because the drawings from Soane's office show the design in development and sometimes present conflicting information. I have been exploring this series of spaces as variations on a common theme.  All of them have central domes buttressed by 4 vaulted bays and 4 smaller spaces in the corners.  Like Soane I started with the Stock Office, which has been renovated to house the current museum. This was fitted into an existing rectangular space to replace a dilapidated existing hall.  He chose masonry vaults and domes to avoid the problems associated with the previous timber roof structures.

These halls were built, one by one, within existing shells, so I decided to model them first as Generic Model families: simple, quick massing studies to act as a guide to later work.  I wanted to resolve the major issues of scale and alignment before investing too much effort in detail. There are connections between the rooms that need to be lined up and interesting relationships between the various roof levels as they fit together like a jigsaw puzzle with interlocking light wells

I haven't done pendentives before in Revit.  Turns out they are quite straightforward.  Basically we are looking at a device for making the transition from square to circle: taking a dome and bringing it down onto 4 supporting columns.  There always has to be buttressing to deal with the lateral thrust, but the main wait is coming down on the corner columns.  It's clear from the drawings that the roofs are flat, so I made my pendentives from a box cut by a revolve.

In Soane's domes the centre of the dome is often well below the springing point leading to his characteristic shallow arches meeting the columns at an angle. That's how the Stock Office works.

But sometimes he has sufficient height to allow a full semicircle with the dome flowing down smoothly into the columns.  The colonial office is a good example.

So let's take a closer look at pendentive geometry.  I made a basic parametric family to illustrate this.  We start off with a revolve that creates a hemispherical shell.  Parameters for inside radius and shell thickness. Formula to add these together for the outer radius.

Now set up a reference planes to define a square.  We're going to use these to control a void in the form of a square donut.  This will cut away the sides of the dome creating 4 arches and 4 point supports.

To complete the picture we need upper and lower cutting planes that can also be varied parametrically.  I've set this whole thing up so that the cutting planes are controlled as fractions of the dome radius.  That way, when you type in a new radius the whole thing scales up while maintaining its basic shape.

The end result is a family with 5 instance parameters that can change its size, an vary between a full hemisphere and one of Soane's relatively flat "canopy domes".  So much for basic dome theory.
A set of pendentives can be used to support a simple dome, or a dome on a drum, or lightweight lantern which is what we see at the Bank of England. In the stock office he uses decorative steel brackets to support the lantern roof, shallow arches at the sides, and groin vaults at the ends which allow for steel framed clerestory windows above the corner bays.  These corner bay receive additional daylight from circular holes cut through the ceiling.

To the left you can see a doorway that leads through to the Old Shutting Room which was the next space that Soane rebuilt, once again fitted within and existing shell of perimeter walls.  You can see from the way that Soane places 4 columns around each of the corner bays that he is not relying on these older walls to carry any load.  Everything can be taken down to new foundations within the interior.

The same strategy is used in the Shutting Room.  The door in front of us is the one we saw before coming from the Stock Office, while the one on the left leads to the Consols Transfer Office which is part of the extensive North-East extension that Soane built over the next few years.  This has already been modelled in some detail by Russell Fuller Hill, an excellent contribution which helped me to build a simpler massing model.

You can see my take on the CTO on the left in orange.  This is again a Generic Model Family, but nested within a link so it can be easily swapped out with Russell's version.  That's the strategy I'm aiming towards here, a series of modules with different versions that can be loaded and unloaded depending on where your focus is and the processing power that you have available.

I haven't gone into as much detail as Russel.  No need to duplicate his efforts, but by standing on his shoulders and with the benefit of the old photographs I think I have been able to progress our understanding of what was actually built.  For example the arches that connect the side bays to the corner spaces are lower in my version.  Russel had followed the majority of the drawings, but the photos suggest that Soane made a late change and one drawing (which I think is a record of progress on site) seems to confirm this.

The photos suggest that the design for the casing to the columns was also changed, simplified down to a single recess with a Greek key moulding for the capital.  These are all subtle changes, but show an ever thoughtful architect reflecting on his design and making late adjustments.  The lower arch in particular has practical implications in that it keeps the crown below the springing point of the arches to the corner bays so that these can have a simple arched ceiling rather than the groin vault originally envisaged.

With some reluctance I have rotated the Consols Transfer Office and the Shutting Room by 1 degree.  This is to line up an axis from the rotunda, through these two spaces to the apse at the end of Lothbury Court.  This also brings the CTO closer into line with Cockerell's plan which we have chosen as our common base and from which I developed my guide grid.  For the moment I end up with double walls with wedge shaped cavities in some locations. 

I think it's important to make the connections between the rooms fall in more or less the right places, and to maintain the most obvious axial alignments.  I am intrigued by this aspect of Soane's work: how he adapted to the difficult angles he inherited and created spaces that may look slightly awkward in plan, but would have flowed quite naturally and regularly as a walked experience.

It also strikes me that the CTO does not have full columns up against the perimeter walls, like the previous two banking halls.  This suggests that the walls themselves are loadbearing, which is logical enough given that this is a completely new extension.  These are the kinds of insights that I believe justify the use of BIM on a historical research project of this nature.  Revit makes you think like a builder.

And as an ex-bricklayer, I do hope I can find time to model the construction of part of one of the roofs over these vaults and pendentives.  The drawings show "crop walls" which I would have called "dwarf walls" and spanning over them "York Paving" slabs, which is basically the same material that I saw used for the floors in the reconstructed Stock Office.

 Was that the final finish?  What about waterproofing ?  A roofscape photo shows sheet metal on a portion of flat roof around the lantern, but this could have been added later. 

Oh and the three black holes at the end of the CTO in the drawing ?  I'm quite sure these are skylights in the ceiling of the passage leading towards the Consols Library, which is directly behind the exterior screen wall and therefore has no windows.  It was accessed via half a dozen steps at the end of the CTO. 

They would have been very similar to the ones in the Stock Office, probably covered with a small octagonal lantern like the one you can see in this photo that I took from inside the museum.  It's a bit washed out, but clearly visible.

 

PROJECT SOANE - A SENSE OF SCALE

Four weeks ago I dragged my son Tom around a bunch of John Soane buildings in London, taking photos like a nutter.  There are 3 churches, his tomb, the Dulwich Picture Gallery, his house in Lincolns Inn, and of course the Bank of England (what's left of it)  I didn't get around to Pitzhanger Manor or the Chelsea Hospital Stables, but I did pick up some books which reference these and other project that are either outside London, have been demolished, or were never built.

All this, inspired by Project Soane.  Look it up if you don't know.  I'm very excited to be contributing to this initiative which brings into the public realm ideas I have been banging on about for some time now.  In particular the belief that the BIM pencil is an amazing tool with applications way beyond what we do in our day jobs: education, research, publications, history of architecture, history of civilisation, lots of stuff that we have been doing with ordinary pencils since before John Soane was born in a village near Reading, son of a bricklayer, destined to rise to dizzy heights in an age of revolutions.

The next weekend was spent in Somerset, with my old schoolboy mates Ian & Al, plus other friends picked up over the ensuing 50 years or so in various parts of the world.  The 3 of us went to Barnsley Grammar School back in the ice age, or rather the "swinging sixties" and have had a passion for music ever since.  We have a band, affectionately known as the Barnsley Vista Social Club, which meets occasionally and gigs about once a year, basically when I'm in the same hemisphere as the others.

Down in Somerset we stayed at a place with definite sixties connections, pictures of Lulu and Engelbert Humperdink who stayed there when it belonged to a musician of the era.  The gig itself was in the village hall just across the road from where Al lives.  We had a brilliant audience, many with definite 1960s credentials, who got up and danced when I broke into my Howling Wolf impression.  It was a night to remember and we raised a surprising amount of money for Nepal in the process.  What a privilege to have shared my youth which such remarkable people.

For the last 2 weekends I have been busy with my BIM pencil, exploring the Bank of England as it was around 1830, when Soane retired, Napoleon was a fading memory and railways were about to burst upon an unsuspecting world.

I decided to start (as I usually do) by getting a sense of scale and an overview of the whole building.  Screen grabs from Google Earth and Bing Maps both give similar results.  Google Earth has a long scale bar that resizes dynamically as you zoom. Very clever, but perhaps misleading.  I don't think we can be so sure about the accuracy of the scaling of imagery that is assembled "automatically" from various aerial sources.  Perhaps Bing is a little wiser in just giving us a short bar with a rounded off value.

Fortunately we have a couple of plans that were drawn up by architects that followed Soane. (Cockerell was one) There are also dimensioned drawings for rooms like the Stock Office that has now been lovingly restored as the Bank Museum.  So I was able to do a cross-check on the overall scaling.  The result is my best guess at a filled region to represent the bank perimeter and the positions of the couryards and light wells that existed when Soane had finished weaving his magic.

I have deliberately set the two main corners at right angles.  Almost certainly this is not quite correct.  Life never quite lives up to these abstract ideals.  I'm sure Plato would have agreed with me.  We have no choice but to simplify.  There would be no point in trying to record every millimetre of deviation from an ideal plane.  The question at hand is "how much to simplify".  I have chosen to use right angles wherever possible.  Deviating by fractions of a degree is not something Revit likes to do.  We would be mad to attempt it.

Taking this discussion a step further, I felt the need for a grid.  This helps us to orient ourselves when jumping from plan to section to elevation.  I find grids invaluable in helping to minimise human error.  Revit has wonderful grid and level tools (best in class springs to mind)  Let's make use of them.  Feel free to argue otherwise.  Now is the time to hammer this out.

I have also chosen to space my grids at round-figure intervals.  The position of walls in relation to these grids will be subject to revision as we go along, but let's keep things simple if we can.  Perhaps we will decide to rotate one or two walls by a degree or two relative to the grid later on.  This may be the only way to make sense of window spacings for example in some of the internal courtyards.  But I propose to start by setting all walls parallel to the three sets of grids that I have prefixed with A/B, C/D & E/F (A being at right angles to B, etc)

I would have liked the angle between Princes Street and Lothbury to be 60 degrees (wouldn't we all).  Sadly it is not so.  I started with 61 but later adjusted this to 61.5 in order to make Tivoli Corner work.  It's a mission to rotate whole sections of the grid, so I hope we don't have to do this again, but you never know.

I am also assuming that certain sections of the facades are perfectly symmetrical with well defined mirroring axes.  We will get in an awful muddle if we don't do this I think.  Clearly that was Soane's intention which is more than good enough for me.

Similary the walls are at present defined in multiples of six inches.  Which brings me to the topic of units.  Most of the world works in Napoleans units.  Despite claiming to be the world's greatest democracy, the US cannot get past the Imperial System that it inherited from its former colonial masters who invented the Bank of England way back in 1694.  Soane of course also used this system, despite a certain admiration for Napoleon implied by items in the unbelievable collection of artefacts, paintings and historical relics that he assembled in his house, now the Soane Museum in Lincoln's Inn Fields.  Take a visit if you ever get the chance.  To say he was obsessed with the classical period and a man of the most remarkable energy and dedication would be a huge understatement.  Also his fascination with effects of space and light is brought to life here in a way that words or even pictures could never convey. 

At primary school with my mate Ian, I used feet and inches.  The metric system came upon us after we joined Alan at BGS if I remember rightly.  In my bricklaying days there was an overlap.  We measured brickwork in millimetres, but timber sizes still tended to be thought of in terms of 2 by 1, and 6x2.  Strangely in the UAE we still measure floor areas in square feet, even though everything else is metres and millimetres.  I am struggling a bit with my memory box, but it's fun to work in unfamiliar territory, kind of like playing the blues in A flat perhaps.  Unexpected insights.

There is a splendid drawing that was provided on the Project Soane site which has the perimeter wall in plan and elevations arrayed around.  Many of these are in pairs showing Soane's "before and after" vision for transforming the work he had inherited from the two previous architects of the Bank.  I cut and pasted sections of this as backgrounds for my 4 principal elevations and scaled them up as best as I could.  This gave me a basis for deciding on the vertical scaling.  After some experimentation I have settled on a figure of 25 feet for the height of the Corinthian Columns and Pilasters that feature all around the perimeter at various points.  This may well be wrong, but we have to start somewhere.

The stonework is set in horizontal bands with recessed horizontal joints and flush verticals.  Many architects have used this device, Wright for example was very fond of it, witness Robey House.  Using my 25 foot guesstimate, these bands would be spaced at 1' 4".  This can be easily checked (I'm embarassed that I didn't think of it when I was there)  Maybe I will ask my son Tom to nip down with a tape measure some time. 

I've done a few of these kinds of studies before. (Ronchamp, Casa del Fascio, Lever House, the Gherkin, Robey House, De la Warr Pavilion ...)  You can never nail things down 100%.  There are always little anomalies and discrepancies that I fail to resolve completely.  Photos say one thing, plans another, elevations and sections something slightly different.  The St Bartholomew's Lane elevation in Soanes drawing does not match the plan drawn directly above it.  He gives two elevations (before and after) but neither of them match the plan.  Clearly he changed his mind about how to modify the frontage he had inherited from Taylor.  I am following the plan, which tallies well with a historical photograph taken in the 1920s. 

Actually I am giving preference to the plan drawn by Cockerell. This is the one supplied on A360 and used as an underlay in most of the uploaded Revit files.  It's not perfect, but it seems to be the best we have.  The BIM pencil allows us to coordinate plans, sections and elevations with a precision that was unavailable to Cockerell, so I've made minor adjustments here and there.  Bear in mind also that even if he did become aware of discrepancies half way through the drawing process he would most likely have faked some of the dimensions rather than start the drawing again from scratch.  That was the reality we faced when we worked entirely by hand.  You took more care to get things right first time, but at some point in the process you were forced to accept the small errors that had crept into a set of drawings that might represent hundreds of person hours.

 

In the spirit of crowd-sauce I wasn't going to make the blind windows from scratch.  I had been using a simple rectangular recess, good for starters, maybe I will go back to that later on and represent the bank as a very simplified abstraction to show what we have learnt about the composition.  Some good work in the family I downloaded, but I needed to adjust the proportions to suit my assumptions.  Don't know for sure who's right on this, but I need to follow through consistently with the line I've taken.  Also the head and sill were not quite right on closer inspection.  So I gave them a bit more depth.  I'll come back to this again later perhaps (or someone else will grab the baton) but for now it does the job.

Another week has gone by since I started this post, so I need to wind it up.  My last image will be based on two photos I took at the Dulwich Picture Gallery on a beautiful sunny day at the beginning of August.

I think it's not too far-fetched to say that the red telephone box is a precursor to wi-fi spots, which is not to say that John Soane invented the internet, but there is a connection and it has to do with style.  Style matters to humans.  It mattered to our ancestors a million years ago when they made symmetrical flint axes and it matters to those who purchase apple's exquisite digital toys. 

Monuments use style to convey respect for past events and personalities. Soane had a thing about shallow domes with segmental pediments.  Giles Gilbert Scott re-purposed this stylistic motif to add dignity to the democratisation of telephony, which brings us back to the public telephone box: access to global communications for the man in the street, just like today's smart phones.

Important questions.  What was Soanes "style" all about?  How do we capture the essence of that style in a BIM model?  Why are we doing this in BIM (as opposed to visualisation software)?  What is the most appropriate level of abstraction/simplification?  Can we find a flexible approach to LOD ? (strategies for switching between levels of abstraction, swapping out components etc)  What is the balance between product and process? Showing off v learning?  Visualisation v Historical Analysis? Recording the past v exploring interpretations.

More to come, day job permitting.

For those who don't have access to Project Soane, and/or Revit 2016 here's a link to a PDF of my work so far.

Bank of England.pdf