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English summary
BMW Welt
Premium architecture for a premium brand –
BMW Welt was designed to fulfil that ambition.
A building that would project the dynamism and
innovative character of the brand and provide
space for a variety of uses. The winning design,
chosen in 2001, was an avant-garde solution
by Professor Wolf D. Prix and COOP HIMMEL -
B(L)AU of Vienna: a ‘cloud-like’ roof emerging
from a double cone, symbolising movement,
change and dynamic forces. Turning this vision
into reality was a tremendous technical and
logistical feat, requiring state-of-the-art computer
technology to master the structural
calculations involved. In October 2007, this
milestone of modern architecture opened its
doors to customers and the general public.
Located opposite the company’s landmark
quatrefoil tower and museum, and close to the
Olympic Centre with its famous tented stadium,
BMW Welt houses a flexible, multifunctional
‘brand-experience’ space for exhibitions,
product presentations and car deliveries.
Double cone
The key to the implementation of this expres -
sive form is the 28 m high double cone, 35 m
in diameter at the base, tapering at rough ly halfheight
to 18 m and widening again to 45 m at
the top. The original plan for a primary and a
secondary frame for the cone was optimised
to create a single load-bearing façade, with a
triangular grid structure of hollow-section steel.
The glass skin is attached directly to this grid.
A continuous ring girder finishes off the top of
the façade, bracing the roof of the cone and
providing a fixing point for the principal girders
in the main roof. The unusual shape of the
building demanded great accuracy in planning
and construction. This complexity is evident
not least at the connection points. No less than
900 differently shaped panes of glass were
used just on the façade of the cone. For the
load-bearing steel façade of both cone and
main section a patented system of hollowsection
steel was used in which water is cir -
culated for heating or cooling purposes. This
both solves the problem of condensation in
the high interior and ensures a comfortable
indoor climate throughout the year.
‘Cloud’ roof
Functionally, structurally and above all formally
the roof of BMW Welt and the double cone
form a single integrated structure. For the main
load-bearing axis in the roof 5-m spaced double
trusses were chosen, each pair spac ed in turn
at 10 or 15 m. A secondary framework in be -
tween transfers loads to these main trusses.
Little pre-assembly was possible be cause of
the height of the trusses, so all the connections
were carried out on site. A critical aspect
in implementing the ‘floating’ impression was
to have as few visible supports as possible. In
addition to the main bearing points, the 4,000
tonne, 16,000 m 2 roof is supported by a mere
twelve columns. The roof is braced horizontally
partly via the steel frame of the double cone
and partly via connection to the reinforcedconcrete
frame of the restaurant tower and the
composite steel frame of the lounge. Particular
attention had to be paid to these connections
to allow for movement in the wide-spanning
roof construction. Glazed sections in the roof
admit natural light and open up a view of the
BMW Tower. Enclosed within the roof struc-
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ture is the customer lounge, overlooking the
‘Premiere’ space where the new cars are
handed over to their owners. The two office
storeys are located in the ‘fish-belly level’, a
suspended girder-grid structure which also
forms the underside of the ‘cloud’, supported
here on a ‘box’, in the form of the floor decks
and perimeter storey-high trusses.
Façade
The 5,500 m 2 façade of the main section is
a slender post-and-rail system, modified and
tilted to cope with the varying heights of the
roof edge and the complex roof loading situ -
ation.
Bridge
Sweeping through the interior is a footbridge
which arcs around the main public zone, providing
viewing platforms over the exhibits
below. Bearing on the concrete core and suspended
from the roof, the walkway continues
the floating analogy by dispensing with freestanding
columns. It has a steel channel section
frame and trussed girder sides. Passing
through the building envelope on the south
side, the line of the footbridge continues in a
pedestrian walkway leading to the main BMW
complex across a busy road.
Ingrid Taylor