Inside the chapel, the roof support is revealed. Thirty-six regularly
spaced square posts are set out from the interior plywood wall-lining
(Fig. 6.4). Each connects delicately to the wall by three steel pins. The
simple move of withdrawing the posts from their conventional location
within the walls and exposing them affects the interior enormously.
Acting as visual markers, they modulate the wall surface, but also increase
the shape definition of the interior space and accentuate a sense of enclo-
sure by their continuous alignment with the roof ribs they support.
The roof structure possesses symmetry and visual simplicity. The ribbed
pattern of rafters recalls the ribs on the underside of a leaf (Fig. 6.5).
Whereas conventional roof framing usually comprises a hierarchical
structure consisting of transverse rafters above a deeper longitudinal
spine or ridge-beam, all the chapel roof ribs, including the spine-beam
that does not span the whole length of the chapel, are of identical
depth, and each branches from the spine to bear on a perimeter post.
Thin steel plates, welded together to achieve the branching geometry,
are interleaved between timber laminates to achieve a two-way struc-
tural action. Skilfully concealed, the reinforcement does not detract from
the glue-laminated timber construction. Further evidence of detailing
refinement is seen in the shape of the spine-beam itself. Not only trape-
zoidal in cross-section to soften its visual impact, its width tapers in
harmony with the building plan, wide near the front of the chapel and
narrow at the rear. These details that reflect the building form and the
designer’s aesthetic sensibility are indiscernible at the first viewing, but
106 STRUCTURE AS ARCHITECTURE
▲6.4 Chapel interior, facing towards the altar.
▲6.5 Ribbed roof structure.
