Clever but Flawed Addition to UCSD : Design: Gunnar Birkerts goes underground with his expansion of the campus’ landmark library. The idea is perfectly functional, but wear a visor.

SAN DIEGO — Michigan architect Gunnar Birkerts’ addition to UC San Diego’s main library is wildly imaginative but significantly flawed.

Opened in January and designed by Birkerts in association with BSHA Architecture & Planning of San Diego, the $35-million addition to Los Angeles architect William Pereira’s original main library is a two-level underground complex that more than doubles the library’s capacity.

Birkerts has separated his concrete addition from the original structure with a giant, faultline-like fissure. Reflective glass lines the inner edge, which forms one wall of this fissure, drawing in a lot of natural light.

The mound on which the old building rests extends down into these surrounding crevasses in the form of landscaped slopes that reflect natural light into the addition and provide green views. Five crown-like glass skylights on top of the expansion bring more daylight to the underground spaces.

In theory, Birkerts’ design is a perfect functional solution: a sizable, well-lit expansion that preserves the appearance of Pereira’s 1970 landmark.

But the quality of the light inside the new building is eerie instead of cheery. Tinted reflective glass lends odd hues to the natural light. Fluorescent lights inside add different but equally weird tones.

Half an hour inside the new complex induces the same kind of disorienting, headachy sensations one experiences in some department stores and offices. According to one employee, the light quality is so annoying that some workers wear visors.

And, although Birkerts’ 220,000-square-foot design was inspired by the natural phenomenon of fissures in the earth (since the library is near the Rose Canyon fault), nothing could look more unnatural than these glitzy, mirrored walls. They make the building anonymous, cold, inhuman and jarringly in contrast to the rich font of knowledge the library represents.

The addition consists of two L-shaped underground wings that wrap the eastern, southern and western sides of Pereira’s building.

Now that the addition is finished, except for landscaping, the original is closed for renovation. New fire sprinklers and seismic bracing are being added, along with a new elevator. Four tunnels on each level of the addition connect it to the original.

Until the renovation of the main building is done, emergency doors at the southern ends of the new wings serve as entrances. When the whole complex is finished later this year, visitors will enter via a wide, concrete bridge that crosses between the exposed ends of these wings to reach the original main entrance, about 100 feet away.

Experiencing the building is both transcendent and confusing.

Pereira’s original structure was intended as an abstracted “sphere of knowledge.” The addition greets visitors with reflective glass surfaces that mirror people, landscape and fragments of structure in an abstracted collage.

Through the doors is a more tangible real world of people and books, desks and shelves, concrete pillars and outward views.

It’s a strange sensation to enter the addition, descend into the earth and gaze out at views that are pleasing but give no indication as to where you are on campus.

A $400,000 public art installation called “Snake Path,” created by Los Angeles artist Alexis Smith, is a 600-foot serpentine slate path that winds up a slope to the library from the east.

When the path is finished later this year, pedestrians will follow it past a monumental, granite book that quotes Milton’s “Paradise Lost” and a small tropical garden intended to represent Eden. The art was funded by donations to the Stuart Collection, a nonprofit foundation for public art on campus.

Smith’s contribution is well conceived and meticulously crafted, but it’s too bad that this mysterious side trip, added with little communication between Birkerts and Smith, could not have been more integral to the building.

University officials have discussed adding to the original central library almost since it opened.

Although it was an instant landmark, Pereira’s building was also immediately obsolete. It was too small, and its unusual forms created odd interior spaces that were never ideal for efficient storage of books and movement of people.

Also, its original clear glass didn’t protect books from ultraviolet light, and allowed southern-facing interior spaces to get too hot. So the glass was eventually tinted with a stick-on material that wrinkled and cracked.

In the old building, 1 million books had been crammed into space intended for 750,000, and several study cubicles had been eliminated to make way for books. The expanded library will accommodate 1.3 million books and will have 1,400 cubicles, up from 800.

Opinions of Pereira’s building, which spreads outward and upward from its pedestal base like a giant concrete-and-glass tree, vary broadly.

Some critics view it as an architectural oddity like the Seattle Space Needle that has little to do with practical design. Others believe the building is one of the few inspiring works of architecture on a campus overrun by stolid, bleak, 1970s-era concrete structures and louder, non-contextual statement buildings from the 1980s.

Either way, university administrators knew that adding to Pereira’s building would be touchy. So they were elated with Birkerts’ underground scheme.

A disciple of Finnish architect Alvar Aalto, who died in 1976, Birkerts has long shared Aalto’s fascination with natural light.

Birkerts used a similar underground scheme for his 1981 addition to the Law School library at the University of Michigan, a historic Gothic-style building.

The concept he used there is similar to the one he employed at UCSD. A veteran library staff member at Michigan said there have been no complaints about light quality.

Though the light inside the San Diego addition is not as easy on the eye as natural daylight, it is better than pure fluorescent. Different fluorescent fixtures may eventually enhance the interior light mix.

Birkerts’ building at UCSD is not perfect, but it offers an ingenious solution to the problem of adding to a landmark. And, with his respect for the history and gently rolling terrain of the campus, Birkerts’ structure provides an admirable model for future generations of university buildings.