Selected Bibliography Architecture - Form Space and Order | Page 133
O VE R H EAD PLANE
Similar to the manner in which a shade tree
offers a sense of enclosure beneath its umbrella
structure, an overhead plane defines a field of
space between itself and the ground plane. Since
the edges of the overhead plane establish the
boundaries of this field, its shape, size, and height
above the ground plane determines the formal
qualities of the space.
While the previous manipulations of the ground
or floor plane defined fields of space whose upper
limits were established by their context, an
overhead plane has the ability to define a discrete
volume of space virtually by itself.
If vertical linear elements such as columns or posts
are used to support the overhead plane, they will
aid in visually establishing the limits of the defined
space without disrupting the flow of space through
the field.
Similarly, if the edges of the overhead plane are
turned downward, or if the base plane beneath it
is articulated by a change in level, the boundaries
of the defined volume of space will be visually
reinforced.
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