The facts
Client - Timber Connections Ltd
Location - Marlowe, Ramsgate
Completed - 2005
Value - £25m
The project
Capita Symonds provided structural engineering services
on the feature timber roof for the £25m Marlowe Academy project in
Ramsgate.
The new school, which replaced the much maligned Ramsgate
School, was the first academy to be built in Kent, the largest
Local Education Authority in England. Home to 1100 students
aged 11-19, the Academy has specialisms in performing arts, sports,
and art and design which have been physically interpreted in the
building as three curving petals that fold together around a
central void.
One of the school’s key features is an award-winning timber roof
- designed by Capita Symonds - which is made up of triangular grids
arching over a huge four-storey high, 20m wide, column free,
crescent shaped central space.
The triangular grids consist of downstand ribs, all in exposed
timber, that support the roof deck directly above. The strength of
the shell is derived from the jumbo-thickness, high-strength
plywood used to make the ribs; the unobtrusive connections at the
nodes where the ribs meet comprise special steel rings with angled
spurs that are bolted into the ends of the ribs; the shell’s double
curvature in plan and in section; and lateral restraint which is
provided by perpendicular concrete walls within the classroom wing,
and raking steel struts in the auditorium wing.
The shell’s complex curvilinear geometry was devised with the
longitudinal ribs following a series of concentric circular arcs
that match the crescentshaped plan of the arena. The sectional
profile of the vault is made up of two different curves with a
relatively sharp curve rising up from the classroom wing which then
converts into a gentle arc that flows down to the lower auditorium
wing and matches the shape of its roof.
To add to the complexity, the ribs that span diagonally across
the vault are also curved in plan which helps maintain an even
spacing between the
longitudinal ribs, resulting in a regular grid of triangles across
the whole roof.