Serving two masters is no easy task. When those masters are superstar architect Frank O. Gehry and Thomas Krens, director of the Solomon R. Guggenheim Foundation--and the project at hand is lighting the $100 million Guggenheim Museum Bilbao, in the Basque province of northern Spain--the stakes rise sky high.

The museum project came about as a result of the fortuitous meeting, in 1991, of Krens and the Basque administration. Krens was looking for additional venues to the New York and Venice Guggenheims in which to display the foundation's vast collection of modern and contemporary art. The administration, meanwhile, had earmarked $1.5 billion for the urban and cultural redevelopment of Bilbao, a city whose once-profitable manufacturing and maritime industries were in deep recession.

The two parties reached an agreement whereby the Basque administration would cover the $100 million in building costs, operational and maintenance expenses, as well as curatorial and administrative services to be provided by the foundation. It also set aside $50 million for acquisitions for the museum's permanent collection.

Invitations to compete for the design of the museum were sent to Arata Isozaki of Japan, Coop Himmelblau of Austria, and Frank O. Gehry of Santa Monica, CA. Gehry's design was chosen for the Guggenheim Museum Bilbao, the museum Krens proclaims to be "the greatest building of the 20th century" and Philip Johnson calls "the greatest building of our time."

Once Gehry had developed the schematic design for the building, in 1993, he contracted Lam Partners Inc. to join his team and design the lighting for the 349,000-sq.-ft. site (31,410 sq. m) and the 257,000-sq.-ft. building (23,130 sq. m). Lam Partners is a nine-person lighting design firm, located in a renovated warehouse in Cambridge, MA. Its principals, Paul Zaferiou and Robert Osten, had worked with Frank O. Gehry & Associates before on projects including the Walt Disney Concert Hall in Los Angeles, the Boston Children's Museum, and the Museum of Decorative Arts in Montreal.

Gehry loves sunlight; the Guggenheim fears it, with an eye toward conservation. Lam Partners was separately interviewed by the Solomon R. Guggenheim's project team in New York and the lighting contract was approved only after Lam Partners' assurances that the Guggenheim's lighting design criteria would be incorporated into the design of the Guggenheim Museum Bilbao's lighting system. Hence two masters.

Lam Partners is hardly new to major architectural contracts. The 30-year-old firm, most of whose members are registered architects, has provided services in artificial lighting design, daylight design and analysis, lighting for urban design, and master planning for jobs ranging in size from lobbies to billion-dollar airports. Its quantitative calculations, which refine and prove their designs, are supported by Lumen-Micro computer modeling, Sun-Scan, its proprietary daylight testing software, and an extensive electronic database of luminaire photometrics. Nevertheless, the challenge of lighting the Guggenheim Museum Bilbao, an ocean away, was daunting.

Lam Partners was responsible for the complete lighting of all aspects of the site and building, including the galleries, atrium, conservation labs, support spaces, auditorium, restaurant, retail and administration areas. The outdoor lighting encompassed a main plaza, entry signage, a riverside promenade, the open tower structure, and employee and circulation areas. Enrique Rojas, senior associate at Lam, was the project manager who coordinated the lighting layouts, details, and fixture specifications with Gehry's office. His fluency in Spanish was a great asset during the construction phase.

Gehry worked with a profusion of intricate, detailed models for each of the Guggenheim Museum Bilbao's 19 galleries. Rather than merely placing a task light over the models, Lam's Robert Osten wrote a computer program, put into a database, which could factor Bilbao's latitude, time of year, and time of day into the calculations. In this way, Gehry's models were "test driven" on a tilt-table placed on Gehry & Associates' Santa Monica office roof. The computer would take readings of how much light was hitting the walls and "normalize" them for Bilbao according to seasons (summer, equinox, winter) and time (8am, 10am, noon, 2pm, 4pm, and 6pm). This testing process identified the times of year when daylight exceeded the Guggenheim's criteria of 10fc for specific galleries and the percentage of light reduction required. In addition, a video camera, secured to the models, produced detailed videos of light variations from sunrise to sunset.

Gehry's design is an architectural miracle, a colossal sculpture of undulating, interconnected shapes that rivet the eyes and senses. Mammoth building forms are clad in cream-colored Spanish limestone or ever-changing "shingles" of titanium. Others are vast expanses of glass and steel.

A central, 165'-high (50m), glass-enclosed atrium is the interior focal point from which all 19 galleries branch. It is an awesome space filled with tilting walls, glass elevators, and open catwalks or balconies which lead to the galleries on the second and third floors. The galleries themselves vary in size, shape, and convention, and always point the way back to the triumphal atrium.

Lighting such extraordinary spaces was no easy matter. "The building design presented physical and conceptual lighting challenges," says Zaferiou, who is Lam Partners' president. "The physical challenges had to deal with complex geometries in the central atrium and lighting unusually tall ceilings and curving walls in some of the galleries. The conceptual challenge was driven by Gehry & Associates' goal to create a flexible lighting system that did not 'scar' the ceiling with permanent lines of recessed track lighting."

Lam Partners worked with Gehry's office to develop a unique power point/ power bar system. Special recessed, structural outlet boxes with split-wired receptacles occur in a regular pattern on the gallery ceilings and are regarded as power points. An individual fixture can be directly installed 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. 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. This system provides the required flexibility and the power bars can easily accommodate a curved wall. "Conceptually, this system is unique because the installation of bars is a direct response to the type and placement of the work exhibited. In a subtle way it becomes an expression of the art installation," says Zaferiou.

The Guggenheim Museum Bilbao power system is wired at 220V, which is typical in Europe, but can be changed to any voltage in a fixture by means of transformers. The fixtures are all equipped with a cord and plug for the power point and power bar receptacles. This keeps the system open to use any lighting manufacturer's fixture without a proprietary track system.

The lighting equipment consists of a 220V quartz wallwasher developed specifically for the project that can accommodate a range of lamp wattages and three different object light fixtures to target paintings and sculpture. The three object luminaires--small, medium, and large--cover a full range of beam spreads and light intensities. Due to the museum's very high ceilings and the need for precise beam and glare control, low-voltage object fixtures were specified. The small fixture is a 12V AR111 (the European equivalent of PAR-36), the middle size a 120V PAR-38 with a wide range of wattages available, and the large fixture, a 12V PAR-56 for punch and coverage. Special pendant quartz uplights were developed to light ceilings in galleries, with skylights to balance the contrast between the light well and the ceilings. These fixtures are part of the "kit" of parts available to the curator as part of the power point system. Catwalks solved concerns regarding access to the ceilings. Special art installations can be hung from them.

Skylights to provide ambient light in the galleries were an integral part of Gehry's vision for the museum. Guggenheim conservation requirements included the provision that the skylights be selectively diffused or blacked out, depending on the light sensitivity of a particular installation. Motorized fabric shades, in various degrees of light reduction percentages, are installed below the gallery skylights and can be activated or retracted into a skylight "pocket" through the lighting preset control system in each gallery.

Each entry area has an eight-button lighting control station which can create eight different scenes in each gallery. Lights can be activated for wallwash, object lights only, uplighting, maintenance lights, or various combinations. The individual stations are also linked to a central lighting-control computer system which is locked out during public hours.

The skylights in the galleries were designed to provide the desired clear sky view and meet the art conservation requirements. The laminated skylight panels contain 50% transmission glazing with an added 50% frit pattern and a UV-blocking coating. The frit was added by means of ceramic dots which are invisible to the eye at the gallery heights.

Six of the upper floor galleries are classical, traditional rooms, 60 sq. ft. (5.4 sq. m) and 18' (5.5m) high. Others vary in shape and size from small niches to vast dimensions: The Boat gallery is 100' (30m) high, 80' (24m) wide and 433' (132m) long, or one and a half times the size of a football field. Its walls curve beneath a vaulted ceiling filled with arched trusses. Industrial-sized works by Richard Serra, Andy Warhol, James Rosenquist, Claes Oldenburg, and Coosje van Bruggen, among others, barely fill the space. The gallery is so long that it passes under one of Bilbao's oldest working bridges and culminates in an open tower, the highest point of the museum, on the other side.

Gehry felt the need for a tower, which is solely a sculptural element, and after experimenting with 20-25 models, settled on an open steelwork structure clad on three sides with Spanish limestone. The stones were bolted onto the steel without the use of mortar, leaving slits of light between them. At night Lam Partners makes the tower glow by means of large fixtures bolted within it, which aim the light from the inside out.

In the plaza leading to the museum's main entry, a small number of pole-mounted, halide downlights were used to provide ambient lighting. Polished stainless steel letters, which spell out "Guggenheim Bilbao Museoa," are installed on a steel-and-glass frame and are backlit at night with light reflected from the Spanish limestone-clad wall behind them. A giant front- and backlit poster board scrim, stretched over a separate steel-and-glass frame, identifies the museum's current exhibit, The Guggenheim Museums and the Art of This Century. Flanking the entry plaza is a bright, royal blue administrative building which is efficiently lit to provide light-filled workspace without glare.

Inside the museum, adjacent to the main lobby, is a unique auditorium for films, lectures, and special presentations. The 6,400-sq.-ft. (576 sq. m), 350-seat space is clad largely in Douglas fir plywood. The curving plywood ceiling panels are perforated with 1"-diameter holes to balance the acoustics. For low-level downlighting, a dimmable fiber-optic system was installed with end fibers occurring in a random pattern above some of the plywood perforations. A catwalk hangs midway in the space for stage lighting, wallwash, and higher levels of general illumination.

Rogelio Diez, manager of facilities for the Guggenheim Museum Bilbao, has nothing but the highest praise for Lam Partners' lighting. His on-site, hands-on participation in the museum project from the beginning, as the person responsible for realizing the building's designs locally, makes him a more than credible witness. "There were two aspects to the lighting--lighting of the building and lighting of the art. The concepts emphasized flexibility," Diez says. "Lam Partners' boxes, power bars, and the ability to modify each outlet's intensity by a central control system as well as each gallery's individual control unit, has achieved the goal of having uniform light on all gallery walls. Most of the interior lamps are halogens. There are 2,000 circuits in the building and 1,375 power boxes (two circuits each), but not all of them are used at the same time. We used about 35% of them for the inaugural exhibition. The great advantage of the system is that if light fixtures are not needed, the ceiling is clear."

The development of the Gehry/Lam Partners design was a drawn-out process. Ten prototypes were created for the power point concept in Spain alone and at least 20 in the US. Philips Lighting provided the power points and some of the power bars as part of the base building contract. The wallwasher fixtures, uplights, and additional power bars were eventually manufactured by Lledo of Spain, after a two-year trial period. Erco of Germany was responsible for the focus fixtures.

"A little thing changed each time," says Diez. "Each component had to be just right. The plugs [power bar] had to be very slim, flat but rigid. They could not be done in aluminum; it had to be steel. It was a great relief and highlight to see the last prototype. It is easy to install in ceilings which are very high and can be changed with one hand holding the bar, the other changing the fixture. The Guggenheim lighting team from New York, who lit the inaugural show, were very pleased with the system.

"We comparison-shopped on all components, worldwide, based on quality and price," Diez adds. "We were open to all the world in view of future maintenance as well. Lutron, an American firm, designed and manufactured our computer-controlled lighting system because it was exactly what we wanted and cheaper than a European company. Everything was difficult, but once it was finished it was pleasure and relief. I have nothing big that worries me."

Architect Matt Fineout, a member of Gehry & Associates and on the Guggenheim Museum Bilbao team, elaborates on the success of the lighting system. "Frank wanted to create an atmosphere for the artists. He wanted very evenly lit rooms which directed the eye to the artwork and avoided contrasts. Lam Partners had the technical expertise to execute Frank's ideas and achieve the design goal. They achieved both Frank's and the Guggenheim's criteria. I thought it was very successful."

Indeed. Two weeks after the Guggenheim Museum Bilbao's opening last fall, its hours had to be extended--it is already breaking attendance records, even those of Madrid's Prado. Locals are thronging to see their museum and are dazzled by the building and baffled by the contemporary art. Even doubters, who grumble like the Parisians did over the Centre Pompidou, become instant converts the moment they see it. It is without doubt one of the wonders of the world. As for Lam Partners, "the project has been a four-year roller-coaster ride," says Zaferiou, "but, without reservation, the finished museum is well worth it."

Julie Rekai Rickerd is a Canada-based freelance writer specializing in travel and the arts.

Erco gallery custom lights Erco recessed downlights and accents Philips custom "power point" outlets Philips interior uplight floodlights Philips fiber-optic system (in auditorium) Philips fluorescent battens (in coves) Philips fluorescent lamps Philips and Odelux custom "power bar" system Odelux gallery custom wallwashers Odelux gallery custom uplights Bega exterior low-voltage canopy downlights Bega exterior steplights Sill exterior metal-halide cut-off luminaires We-ef metal-halide high bay downlights Lutron dimming and control system General Electric and Osram Sylvania lamps for gallery object lights