Da Vinci’s famous Vitruvius man may have suggested something to do with human proportions being the guide for all proportions, particularly those of buildings. But this image of a rather long-haired and long-limbed character also points to the key idea that drove so many dreams of the Renaissance – the centrality of the circle as the highest abstract geometric form, and importance of all the other shapes that can be constructed from a circle, not only with one side (circle), but with three, four, five, six, eight, ten and twelve, all perhaps with the exception of the triangle, viable shapes for buildings.

Renaissance designers dreamt of all these forms and gradually came to realise a few in stone. Chief among these were churches, which were, at least in the early days, the highest or most important form of building: the houses of God; and therefore deserved the most pure and singular form: the circle. In this pursuit of the lofty circle, designers sought to dump the older idea of a basilica form for churches: the long layout with low-roofed side aisles that would allow light into central nave from the clerestory windows.   In the early Renaissance there were many trials of many church shapes with elements radiating out from the centre, typically central circles within squares with encircling side-chapels beyond. Doodles by Da Vinci suggest orbiting moons sometimes uniformly floating, and sometimes more embedded and sometimes threatening to dominate the central ‘planet’ (see image).   There is a heavenly feel to these designs, not only in the almost dream-like state of the designers exploring idea after idea as they entered his head, but the domes were often envisaged as intermediaries between earthlings and the firmament, and often were decorated with stars and other heavenly bodies.   Of course, these lofty buildings should be as close to the stars as it was possible to be that is elevated above the surrounding town and preferably on a hill or high point – singular and separated.

The new St Peter’s Basilica in Rome begun in the early 16th century set the new direction: henceforth a church would be centred on a domed space.   Ideally this was to be a Greek Cross, with equal side arms radiating out four ways from the central space, so that the dome remained at the geometric centre not just the symbolic one, but in reality, in the final St Peter’s form as elsewhere, one arm became dominant so that the congregation could be corralled together, focused in a single direction towards the high altar in the east. Michelangelo’s unrealised plan for St Peter’s has an almost abstract 20th century quality about it (see image):  highly organised ink blots; bulbous black shapes against the white of the space; and a central domed circle bounded by almost two outer squares (one on the square and one – not so clear – on the diagonal).

But of course, these ethereal forms were to be brought down to earth. The temptation was too great to reserve them for God alone.   Humans could see themselves being elevated by such spaces.   By at least the late 15th century, architects began applying temple fronts – rows of columns topped by a triangular pediment – to houses.   If human houses were being raised to the level of those of the gods in this way, why stop at the front door?    A whole house could be realised as something close to the ideal.   While he may not have been the first to make the leap of applying the temple front to a house, Andrea Palladio in northern Italy, was one of the first to bring a rigorous centralised form to domestic spaces and cap the whole composition with a dome, most famously realised in the Villa Rotonda on the outskirts of Vicenza (see image, with a Da Vinci inspired church: Santa Maria della Consolazione at Todi by Cola da Caprarola).

Churches can be so pure. They are for a large gathering or people so there is one dominant space, with only small subsidiary spaces, and these virtually hidden away.  This permits a radiating unity of to a church that is hard to repeat in houses.  Practicalities intrude in house, if only because they are a conglomeration of smaller space, spaces that need some separation (even in older times when privacy and personal space was less of a concern).  Even Palladio, who was more pure than most, had to contend with realities or desires of the client: spaces for dining, for private study or reflection or for more public entertaining, plus bedrooms or other rooms for withdrawing.   Houses are invariably smaller than churches and had to be carved into sufficiently large useable spaces.   Houses are also usually in practical places: at the centre of a farm or estate or packed into tight urban spaces.  Maintaining the sense of centralised radiating singular unity is much harder to achieve.

To plan such a house, it will be necessary to accept that there can’t be the kind of perfection that a church can achieve.   There are necessary compromises and it won’t be possible to achieve mirror symmetry on two axes like a Greek Cross.   At Villa Rotonda, Palladio got very close.  There is a tall circular central space capped with dome far above (painted with voluptuous flowery figures suspended on their comfortable clouds peering down at the passers-by), hallways connecting to the outside each way on the two axes, but in order to create suitably sized corner rooms, there needed to be smaller ones tucked in the other axis so there is a symmetry on one axis not matched by that on the other.   Staircases fill the gaps as the curve of the central circle sweeps past the corners of the containing square.

But Palladio managed to point the form towards heaven and the ideals of the early Renaissance, by applying temple fronts on each axis, one for each of the four doors, with pronounced staircases leading up to them.   So the whole composition appears to rise to the peak of the dome: stairs, temple front, central block of the building, the sloping tiled roof and finally the curve of the dome.   Of course, the genius of the whole thing is the choice of site.   Perhaps he only pulled his highest form out of his bottom draw, when he had both the right client (who would appreciate and use this form of house) and the right site: the small hill that allows the form to be elevated on any approach.

But the puzzle in this story is why so many of his followers so obviously failed to reach for the stars.   Perhaps the architectural gods weren’t propitious, as in so many cases the unity or singularity of the idea was lost.    Palladio’s one-time pupil Scamozzi at his Villa Rocca Pisana appears on first approach to maintain this sense of elevated circularity but once close it is apparent that the approach axis dominates both the internal arrangements and external form with the single embedded temple front not repeated on other sides. When the English attempted to emulate Palladio, they succeeded in some ways and failed in others.   Despite securing many of his drawings, Lord Burlington managed to create a domed house at Chiswick that in many ways has a superior radiating floor plan, but constrained by the flat site not too far from the Thames and needing to create a dominant front façade, destroys the transition to an elevated double axis four-sided exterior.   Colin Campbell managed to stick more closely to the original at Mereworth Castle in Kent but the flat land, the excessive emphasis on the front axis (which seems unnecessary in this open country) and the internal layout confused by a long gallery, again weakens the composition.    Later, over the Atlantic in Virginia, Thomas Jefferson at Monticello offers a domed central space but this and the accompanying external temple front are plugged into an otherwise fairly linear arrangement.

To rebuild a house based on a circle now is not simply to engage in a contest with these architects. If Classicism is about reaching for perfection, or at least the ultimate, the centralised house form is more elevated than most.   It is a natural progression to begin from a single centre and allow all elements to radiate out from this, or at least expanding outwards in a somewhat ordered and balanced manner, probably along two axes.

Attached images show some centralised plans for contemporary homes of varying scales, some with a central covered space probably domed, some with central courtyards either partially covered or fully open, some with almost perfectly symmetrical arrangements in all directions (symmetry about each cross axis), another based on a regular Palladian plan, and yet another with apparent symmetry but with the complex conflicting layout of the smaller rooms carefully hidden. Some three dimensional images of partially constructed or deconstructed (ruined) buildings indicate something of the forms.