lightfair international - Illuminating Engineering Society

museums of past eras.
The spatial organization of the 300,000 ft 2 structure is
composed of groups of distinctly shaped galleries that Gehry
swirled around a central atrium and froze before colliding
with one another. The catalytic space is the 50 m high atrium—a
kindred gesture to the Guggenheim’s now symbolic
rotunda in New York.
The galleries range in size and shapes, from rectilinear conventional
forms to curvilinear walls. At other times they seem
like spaces within spaces, sometimes separated by partial height
walls that act like visual funnels. Ceiling heights range from 4.5
to 20 m, arranged in flat, sloped, or curving planes, at times
interrupted by rectilinear skylights with organic shaped wells or
structural beams. Each space has its own unique spatial quality
and character, so much so that the gallery designers nicknamed
them “Nemo,” “Zorro,” “the Boot,” “the Boat,” and so on.
Outsiders on the Inside
“As an outsider it was intriguing to observe the Bilbao studio
designers prepare for a design review,” Enrique Rojas said of his
experience working with Gehry’s studio. “They scurried
around to pull together the assortment of large scale models to
an assemblage approximately 6 x 12 ft in size. Crude as the
forms seemed, they fit beautifully. Minutes before the design
session, the team gathered in almost orchestra form and waited
for the conductor to descend from the upper floor.
“Gehry moved pieces here and there, studied the shapes and
one got the distinct sense that he used every square inch of that
building to express his ideas. Everyone listened with absolute
silence and attention.”
Without the use of the large scale “work models” of the
gallery spaces, it would have been almost impossible to imagine
the geometry and luminous qualities of each gallery. The
designers explored numerous ideas for providing indirect and
object lighting placement—from movable light-columns to
Gehry loves sunlight but precious artwork
doesn’t. To minimize light damage to certain
types of artwork, the museum established
a maximum combined illumination level
of 20 fc incident on the art surface.
pendant horizontal ladders and to
“pick-up sticks” suspended from
concealed motorized lowering
devices and catwalks.
To study the placement of object
(i.e., art) lighting, the designers used a
series of vertical cross section diagrams
to help establish strategic fixture
locations (set at the intersection
between 30 degrees from nadir and
1.57 m above floor level) to light the
art walls and possible sculpture or
temporary wall-mounted exhibits. To
keep their sense of scale in these large
and colossal spaces, which were
drawn in metric scale, Zaferiou and
Rojas often sketched in people and
possible sculptural art pieces. During one of his visits in Bilbao,
Zaferiou was shocked to see Claes Oldenburg’s Swiss Knife
exhibited in the Boat Gallery, “just as we had amusingly shown
it in our lighting study sketches three years before the opening.”
Let the Sun Shine In!
Frank Gehry loves sunlight and the Guggenheim’s conservation
staff fears it, and with good cause. To minimize ultraviolet
and infrared radiation damage to certain types of sensitive artwork,
the museum established a maximum combined illumination
level of 20 fc (215 lx) incident on the art surface, with a
2:1 uniformity ratio on the display walls.
Lam Partners Inc.’s capability in understanding and predicting
daylight illumination levels and direct sunlight path travel
in the exhibition spaces was an important part of the lighting
analysis process. Given the large-scale gallery study models
produced by Gehry’s office, physical model testing was the best
way to study and measure the amount and effects of daylight
and sun path entering the art display areas.
The designers were thankful for Gehry’s models, since there
is no substitute method available for observing daylighting
design in a building, especially in structures of the museum’s
complexity. A case in point was the visual information that the
models relayed to the designers. During daylight testing they
noticed that in the large high spaces with skylights, the ceiling
went dark during strong daylight conditions. Working with
accurate physical models, Zaferiou and Rojas detected the need
to add indirect ambient light to balance the brightness ratios
between the skylight wells and adjacent ceiling planes.
To help quantify and measure the natural lighting, the
designers used the firm’s proprietary software program called
SunScan (developed by Robert Osten, Principal) to test the
architect’s study models. The program reads information
measured through light sensors that are placed in the models
and normalizes the data for the latitude in Bilbao, Spain (or
anywhere on the globe).
To record the sunlight paths, a special rotating table was
designed that calibrates the sun’s geometry between the test site
and the project site. A miniature video camera was installed in
the models to record the daily sun path in each gallery for different
times of the year at typical Summer, Winter, and
Equinox daylight conditions. The invaluable information
recorded in the videos was enhanced with dubbed in music
and visual graphics to label hours of the day and seasonal conditions
at a local television studio and then presented to the
museum’s staff for evaluation.
This Guggenheim Museum has more daylight fenestration
than most museums, but through the use of carefully selected
glazing materials (made up high daylight-low UV-transmission
glass, frit glass sandwiched with UV absorbing interlayer) and
motorized shades the light levels are maintained according to
the museum’s criteria.
Lighting a Modern Masterpiece
The lighting design for this uniquely modern building is
responsive to the complex nature and power of the major volumes
and interstitial crevices, which seem to multiply at every
turn and junction. “Without our constant coordination with
the design team and review of the work models it would have
been impossible to layout our design in two-dimensional format,”
explains Rojas. The design team’s intent was to create
spaces which evoked the “artist-in-residence” idea, and the
lighting design would contribute to this goal.
Unlike American lighting designers, Europeans seem to
design with higher levels of glare tolerance and use fluorescent
and metal halide sources in addition to incandescent sources.
Given the high ceilings in the museum, the selection of
European lamps was limiting. After researching light sources
and fixture manufacturers in the European market, and considering
special 220 V electrical power characteristics in Spain,
it became clear that the fixtures for the
galleries would be custom designed.
“The building design presented
physical and conceptual lighting challenges,”
says Zaferiou. The physical
challenges had to deal with complex
geometry of unusually tall ceilings
and curving walls. The conceptual
challenge was driven by Gehry’s goal
to create a flexible lighting system that
did not “scar” the ceiling with permanent
lines of recessed track lighting
and that would be relatively easy to
maintain. Gehry instructed the lighting
designers to “create a bag of lighting
tricks,” and informed them that
he “would not be opposed to using a
In the galleries, a family of lamps was
needed that had a range of wattages
and beamspreads to properly illuminate
the artwork in these diverse spaces.
non-traditional system of lighting, as long as it was not too visible
and not an aesthetic imposition in the building.”
The designers worked with the architect’s highly creative
staff to further develop a unique power-point and power-bar
system that Gehry first conceived for the Weisman Museum in
Minneapolis, MN. Special recessed, structural outlet boxes
with split-wired receptacles occur in a regular 2 m 2 pattern on
all the gallery ceilings, and are regarded as power-points. An
individual object light fixture can be directly attached to these
points on special clamping bars (power-bars) with built-in
receptacles, which can be secured to hold between two and six
fixtures, depending on the length of the power-bar. The bars
can rotate 360 degrees on the power-points, which then offers
more mounting position flexibility than a conventional track
system. A fixture can be located almost anywhere on a gallery
ceiling. In some of the taller galleries, power-points are also
installed on the upper wall surfaces and in light wells for additional
aiming flexibility.
The special power-bar clamping system proved to be a cost
effective alternative to custom curved track, and it is not limited
to any fixture manufacturer. Retractable magnetic covers
painted to match the ceiling conceal the power-points that are
not in use and therefore minimize visual clutter and the scarring
of the ceiling plane.
The Details
In the galleries which have ceiling heights beyond reach by
motorized lifts, it was ultimately decided to provide 11 m high
catwalks in order to suspend the object lights, ambient wall
washers and uplights, and the work lights, and to facilitate
maintenance access without disturbing the art.
Since dimming for light reduction is not desirable in museum
lighting due to color temperature shift, a family of lamps
with a range of wattages and beamspreads was necessary to
illuminate artwork in these diverse spaces. The generous range
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LD+A/April 1999 43