Plinth and Void as Mediator to Ground

From a distance Aalto’s block for the 1957 housing exhibition appears as a slightly cranked slab block. This does, in fact, represent the strategy of the block above the ground level. However, entry is via a void between the two outer parts of the block. The groundscape of this entry void does not follow the outline of the building above – it extends in places beyond the outline of the upper block. The groundscape is a plinth (base or platform) that subtly reaches out into the surrounding site to ease residents into the entry lobbies. It is a covered exterior space paved with cobble stones to maintain the sense of exteriority. Note that the cobble stone ground continues beyond the plinth level out into the landscape. The structural columns interrupt the void space exposing the geometrical resolution of the crank in the slab above (see the paired columns in the middle of the space. Their spacing appears irregular but follows a strategy that sets up a central space within the void. The idea of this void as a continuation of the exterior is reinforced by the resolution of the railings which ‘float’ over the plinth ground. It is only where walls lead into the lobbies that the low wall railings meet the ground, as if to begin the process of constructing an interior. This is further accentuated by two steps leading up to the lobby doors. The void is articulated with benches that provide various focal points within the void, as does the paint scheme on the ceiling.

There are different points of integration between the plinth and the overall slab-form. On one side it is made by the grey band that continues around the entire building, making a material distinction between the zone that touches the ground and the white exterior surface of the dwellings. On the other side, where the ground drops more dramatically away from the plinth level, the outer surfaces are painted white and seems to continue the building form right down to the ground (although the grid patterning isn’t replicated in this area.

The key lessons here are:

  • The idea of an exterior room as a threshold
  • The use of a plinth to mediate building and ground
  • The development of the plinth as an element in itself (it does not follow the outline of the building above)
  • The reaching out into the site to mark and draw residents inside
  • The use of structure to articulate zones and spaces in the void
  • The reinforcement of spatial ideas through material decisions
  • The reinforcement of spatial ideas through detail decisions (‘floating railings’)

Mediating the Horizontal and Vertical

This entry considers the way in which the vertical form of the Unité d’Habitation by Le Corbusier mediates with the horizontal of the ground (the site). The overarching strategy is that of lifting the body of housing to allow the ground to continue, uninterrupted, underneath what would have been a physical barrier between the eastern and western parts of the site. Added to this is a concern with the ground as a natural field. Although Le Corbusier’s own sketches suggest that he wants a continuous natural landscape to pass underneath the building, in fact, there is a different ground condition underneath the slab (i.e. it is a paved, hard ground-scape). So we must assume that it is the continuity of space that is more important alongside a recognition that it would be difficult to grow anything underneath the building itself.

‘Natural’ and ‘biological’ metaphors are used throughout to accentuate the strategy of how vertical meets horizontal. The overall section is conceived like a body; it has legs (pilotis), a body, a heart (the rue intérieure), and a head (roof garden). The piloti are constructed with organic overtones, tapered like legs, rendered in béon brut accentuating the natural grain of the wood shuttering used during the pouring of the concrete. In the interior lobby the concrete is ‘stippled’ with sea shells.

This particular detail isn’t directly related to the problem of related horizontal and vertical conditions but is part of a theme that contributes to the broader strategy employed by Le Corbusier – and perhaps even fair to say it is representative of his philosophy, his world-view (specifically, the role of nature in considering human culture and its artefacts).

The strategy of lifting the housing to accentuate a continuous ground is underscored by the way the organic entry lobby form floats underneath the slab as a semi-independent element. It’s structural, formal and spatial logic are completely different from that of the slab above.

There are several key lessons to take away from this:

  • Le Corbusier takes a clear position with respect to the site, the ground and how a vertical building should meet it. This is not taken to mean that the solution is good, preferred or that it works (that is up to you, with further analysis).
  • A strategy for resolving a problem (the meeting of vertical and horizontal), for establishing a relationship or for joining two elements, could be to not let them touch, to mediate to a gap, space, or a void.
  • Understanding the larger strategic intent (horizontal-vertical relationship) can make clear to you how to proceed with smaller strategic decisions (making of the entry lobby, floating glass vestibule in lobby), material decisions (concrete, texture, form), details (canopy-lobby detail, column-floor joints).

The wall between inside and outside: a concept

The French architect Henri Ciriani used to tell the parable of Michelangelo’s square (an imaginary square that he might draw to start off a design). It stated that when Michelangelo drew a square, all sorts of decisions and conditions were already known and decided. michelangeloplan1aThat is, as soon as you know the length of one side of the square, you knew how high you could go because you know what it was being made of – stone or marble, for example. It also suggested mass, the amount of light that came in, how open or closed it was, and so on. This was given by the limitations and knowledge of available building materials and construction technologies. When Mies van der Rohe drew a square, nothing was decided. That is, with modern building technologies the height, density, character, transparency, etc., are all up in the air. Mies-50-01For Mies, even the fact that he might place steel columns at the corners meant very little. The proposed space could still be very high, or low, very open, or closed, massive or light. In this sense, for Ciriani, modern architecture requires that you decide everything, or put another way, that you determining everything. Pre-modern space was of considerably different character than modern space. The expectations of exterior space (generally public) where well-known as were those of interior space. I would add that Michelangelo’s square determines its walls or piers which in turn determine the relationship between interior and exterior – and it did this with a single gesture. The material was often the same on each side. Modern space is less clear about inside and outside. Picture here any canonical modernist project breaking the box with flowing exterior and interior space together here (Wright, Schindler, Rietveld, Mies). The modernist wall then had to qualify an increasingly uncertain and abstract exterior while qualifying an increasingly polyvalent and abstract interior. I have it from a good source that Herzog and de Meuron choose to privilege the inside or the outside. For example, when they want an exquisite flat and abstract exterior surface this means the details on the interior are often horrid (and vice versa). David Adjaye supposedly demands that both interior and exterior work equally well. This makes things much harder for the designers, detailers, builders and clients. It is not a question of a right or wrong approach; this is simply to say that there is a choice, and if there is a choice there is an issue, there must be something at stake.

It then occurs to me that Louis Kahn understood this problem and came up with an interesting solution. Knowing the differing demands of the inside versus the outside and the difficulty of reconciling these Kahn decided to make the wall spatial. More precisely he doubled most dividing surfaces (as did Michelangelo). salk_sectionFloor and ceiling become two planes rather than one. Exterior walls are doubled – one responds to the exterior, the other to the interior. It’s there in the Adler house, the Esherick house, the Bryn Mawr dormitories, Unitarian Church, Hurva Synagogue, Yale Art Gallery (in section), Salk Institute (see above image), Exeter Library, Kimball Museum (you’ll have to use you imagination with this one), Richards Medical Laboratories, and many of his unrealised projects. By the time he gets to Dacca he’s transformed this idea into something of great complexity – somehow entire buildings are treated as thicknesses. kahn daccaIn one swift move (but remember this took him years to develop), Kahn engages with the problem of modern space, the interior/exterior conflict, and with the multitude of choices brought on by modern technologies. That is, the technology of the outer skin does not have to impinge on the resolution of the inner skin. No compromise is necessary. This is, again, in no way meant to say that Kahn’s solution is best – Adjaye and H&M have taken different positions on this. What all of them recognise is a conceptual understanding of the problem of reconciling inside and outside space. This idea was speculative until I thought of Kahn. The clarity and rigor with which he articulates this notion of the wall and pier turned the hunch into a concept.

Michelangelo had it easy.

Centred, Peripheral and Dispersed Plan Types

Modernist discourse on space often proposes an opposition between spatial organisations that emphasise the centre versus those that emphasise the periphery. Classically planned buildings nearly always put the emphasis on the geometrical centre of the plan (see 1 square, 4 square, 9 square). Modern architects, in their attempt to link interior and exterior space, put the emphasis on peripheral spaces often eliminating a central space altogether. Since the middle of the last century another plan type, dispersed, did away with emphasis on either centre or periphery. This plan type reinforced the idea of networks, nets or labyrinths rather than fixed geometrical figures. For a time these inflections reflected cultural and social belief systems of their time.

Today we can plan as we like; there is no longer a dominant or shared ‘universal’ spatial order.  If anything, our pluralist contemporary values suggest that we must employ a variety of approaches rather than enforce any single one. In addition, we no longer see centralised plans and its implied hierarchy as inherently bad. It therefore becomes more important to understand the effects and implications of centralised, peripheral or dispersed organisations. For example, we should not see these as just geometrical ‘games’ but as different types of spatial intentions. Although modernist plans often avoided centralised spaces they often reinforced a non-geometrical centre or focus. In the work of Frank Lloyd Wright this was often the hearth; for Le Corbusier it was the double height space, designed as the social heart of a project but located peripherally. Read this was we can see that modernist plans had their own hierarchy even while displacing the symbolic centralised space of classical planning. Dispersed plans might be said to privilege movement rather than any particular space or object.

Although we are now free to use any plan type without the restrictions of a single cultural reading or technological constraint, locality and specificity of place can generate a meaningful choice of plan type. In addition, the plan type is no longer an automatic choice (based on the architect’s rigid belief system) but often evolved through a process of design investigations. Nevertheless, you are likely to eventually arrive at one of these plan types. The question to ask is whether the design intention is utilising the right tool (plan type) to be effective and communicable.

Source: Le Corbusier

Villa Rotunda, c.1580, Andrea Palladio. This is a classic nine-square plan following the geometrical schema quite closely. There are subtle adjustments worth noting: the circular central space emphasizing its importance; a non-symmetrical north-south versus east-west layout; achievement of four different scales in room sizes.

Villa Rotunda, c.1580, Andrea Palladio. Typical centralised and hierarchical plan

Frank Lloyd Wright, Martin House, 1906

Frank Lloyd Wright, Martin House, 1906. Peripheral plan with hearth at centre.

Le Corbusier, Maison Citrohan, 1919.

Le Corbusier, Maison Citrohan, 1919. Non-centralised plan with double height social space (at bottom).

Aldo van Eyck, Orphanage, 1962.

Aldo van Eyck, Orphanage, 1962. Example of dispersed or network plan with an emphasis on movement circuit.

Sanaa, Moriyama House, 2005.

Sanaa, Moriyama House, 2005. A contemporary dispersed plan. Note that this plan avoids reinforcing a centre, periphery or a movement system. In this case it is being used to neutralised as many aspects of space as possible.

Skin versus Wall

The vertical surface enclosing your project can be understood as either a membrane – a think veil separating inside and outside – or as a wall – a solid which requires mediation through windows, gaps or openings. The skin or membrane is generally a surface whose primary determinant is the exterior image. That is, it is a skin which wraps the building and whose articulation – joints, ribs, and pattern – is generally graphic in quality rather than directly determined by the interior.

The wall, by contrast, is articulated as a more solid and thicker surface that tends to act more as a mediator despite the fact that they are generally more opaque than skins (which tend to be transparent or translucent). Because the wall establishes an unambiguous limit (visual and physical) there is generally a tendency to be more considered about how connections are made between the interior and exterior. That is, windows are generally set with a greater concern for specific and framed views. Balconies or other punctures act specifically to join inside and outside. As such, although one may see less of the interior through a walled project than as with a skinned one, the relationship between inside and outside can be said to be more precise.

Paradoxically it can be suggested that skins, though often (but not always) permeable tend to draw attention to the surface as an object – a plane – and hence create a stronger barrier to interior/exterior relationships. Walls, through the more carefully and selective connections can act more as a connective surface linking inside and outside in a constructive manner.

Herzog & de Meuron’s Library for the Eberswalde Technical School. Skin. Note the graphical quality of the membrane.


Neutelings & Riedijk’s Veenman Printer building in Ede, Netherlands. Skin.

Neutelings & Riedijk, Apartment Building, Prinsenhoek. Wall. This project uses three different wall and opening articulations in the base, body and attic of the project to create different identities for each part.


MVRDV, Double House, Utrecht, Netherlands. Wall. This project might be seen to be ambigous, as technically the wall is a skin on a frame. However, the specifically created openings tend to render the solid surfaces as solids, and hence wall-like. The main distinction is in the opposition of open and closed surfaces as opposed to the continuous surface treatement of a skin or membrane.

Free Plan, Open Plan, Raumplan

In everyday usage ‘free plan’ and ‘open plan’ are often used interchangeably. They are, however, very distinct. A free plan comes into play when the role of structure is separated from that of enclosure of spaces. Generally, it arises through the use of columns that allow the partitioning of space to follow a logic other than that of the structural grid. In the best demonstrations of free plan (see Le Corbusier) the columns play a spatial as well as structural role, defining sub-zones, passage zones, or used sculpturally to create a greater sense of depth in space. An open span is a plan which is left largely unplanned, as in typical office towers or single space homes. In the first (free plan) there are always rooms, even if they are not entirely closed off, while in the second (open plan) there is only the perimeter.

A raumplan is a planning method based on discreet rooms and a dynamic section. This method places great emphasis on the scale of individual rooms and often requires steps into each room or cluster of rooms. The method largely belongs to the architect Adolf Loos and requires a high level of structural awareness and ability to model spaces.

Source: Le Corbusier & Adolf Loos. See Raumplan versus Plan Libre by Max Risselada.

Opacity, Transparency & Translucency

These are basic qualities of surface. Considering these early on can help you avoid treating spaces as defined only by walls. Opaque surfaces separately two sides completely and fully. The result is physical and visual separation. Transparent surfaces allow full visual connection while creating physical separation. Translucent surfaces create partial visual separation with either full or partial physical separation. A frosted or sand-blasted glass wall allows light and some visual clues to communicate while preventing physical connection.  A mesh or other type of screen allows slightly more visual information while allow facilitating sound and air movement.

Relationships between two spaces can be made complex when you begin to combine these three qualities in a single space or single surface.