Imagine the boundary between inside and outside or between one room and another to be a zone rather than a wall. This will alleviate a number of problems and open up design possibilities. The zone can be articulated as a double wall, thick wall, inhabited wall or thick threshold. This thickness can be used to house storage spaces, mechanical systems, or be inhabited with window seats, built in furniture or other amenities. In some cases you may even be able to house circulation within the zone. This thickness can also be used to allow for differing sizes among adjacent rooms while avoiding an irregular overall building outline. That is, you can allow for differently sized rooms while keeping to geometrical alignments that can help maintain the clarity of your scheme – a series of rooms as a bar or a cluster or spaces reading as single larger figure. The zone gives you breathing room to negotiate internal needs with external clarity. Working only with walls (and particularly with walls of a single thickness) will create problems when you get into larger scale resolution of your design.
In practice you will find that thicknesses are required for many practical reasons – mechanical systems, plumbing, structure, wiring, and so on. It’s a good habit to develop early on.
Spence R. Kass ‘The Voluminous Wall‘ describes how the walls of St. Peters in Rome is really a thick space that is sometime occupied or used to modulate light. The article focuses on this one project but makes links to Louis Kahn and Alvar Aalto.
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