Page 90 - Between light and shade

between light and shade, TRANSPARENCy and reflection

discipline, and its fundamental rules apply more or
less explicitly to opaque materials. The role of light
in architectural modelling is, first and foremost, to
define the spaces, then to “sculpt” the walls using
the shadows cast, and finally to locally cross the
latter, by means of openings, which are necessarily
limited in terms of their number and extent.

It is only quite recently that the development of
glass technologies has enabled transparency and
reflection to play a more significant role in what a
building expresses in its appearance. Nevertheless,
all these elements, whether they are opaque or
transparent, necessarily obey the same rules that
govern a sound construction and are frequently
referred to by the wonderfully ambiguous term
“best practices”.

One of these rules is particularly close to my
heart: the “shadow line” rule. It is derived from
construction common sense but takes its name
from what light reveals about it, and that is what
gives it its place here.

Far from being just a secondary modelling
detail, the shadow line underpins the way in which
we build, being intimately linked to two funda-
mental concepts of architectural form: “drawing”
and the “joint”, which will be examined below.

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