How did you get involved with the Exploratorium?
My first run in with the Exploratorium was as a young architect in 1991 when they sponsored a design charrette with three teams made up of artists, landscape architects and architects. I was on a team with Joseph Esherick, the founder of my firm, and landscape architect George
Hargreaves among others. The lively discussions during those days gave me great insight into this wonderful institution.

Why did the museum move?
I don’t think Frank Oppenheimer, the Exploratorium’s founder, ever saw the Palace of Fine Arts as a permanent home. They had long since outgrown their space and were no longer able to adequately serve visitors. They also train teachers who teach science in elementary schools and had to turn away two out of three due to the inadequacies of their former home.

What was your vision?
To create a transformative place along the waterfront that furthers the mission of the Exploratorium, the world’s leading institution of science, art and perception.

We wanted to create a much more public, dynamic site and to place architecture, landscape and exhibits on equal footing, creating a holistic environment that fosters inquiry and sustains the environment.

Can you describe the design?
The Exploratorium’s new home is the renovation of an ageing pier, where architecture, art, science and site converge. It elevates the museum’s mission as both a destination for experiential exhibits and a research and development facility that creates innovative ways to teach and learn.

Visibility, public access and flexibility drove the planning and design. Situated midway between Ferry Plaza and Pier 39, the new Exploratorium brings to life a previously dormant stretch of San Francisco’s historic Embarcadero waterfront – the city’s front porch. Almost three times larger than its previous site, the new campus uses Bay water as a basis for many new outdoor exhibits, as well as to control the temperature of the museum.

What’s the style?
The complexity of the brief – to design an ultra-flexible building to support an ever-changing array of exhibits in keeping with the Exploratorium’s culture of inquiry – was matched by the challenge of rehabil- itating an existing historic structure in the most energy-efficient manner possible.

Pier 15 was renovated to maintain its historic character and the tinkering studio atmosphere of the old Exploratorium. More like an artist’s studio or an experimental laboratory than a place of display, the building takes advantage of the original pier building’s daylight and the water of the bay for cooling, and uses materials that are both sustainable and durable enough to withstand a harsh maritime climate. The goal is for the Exploratorium to be the USA’s largest net zero energy museum. This, combined with the Explora- torium’s reputation as a hub of innovation, will make the building an industry model for what’s possible in energy efficiency.

And outside?
A promenade encircling Pier 15 and an out- door plaza between the piers enables free interactive outdoor exhibits, Exploratorium explainers, captivating the general public and passers-by with the direct experience of the surrounding bay and the city. This expe- rience begins at the water’s edge to a point 820 feet off-shore. (Pier 15 is the length of a New York City block, avenue to avenue) The plaza and the hum of activity is the new marquee – no signage required.

How about sustainability?
We designed a building that incorporates many energy-efficient elements aimed at producing all of its energy needs on-site.

For example, the 1.3-megawatt photovoltaic array on the roof is equivalent to powering 1,000 average American homes over the course of a year, or removing 5,900 automobiles from our highways. Bay water is brought in and run through a heat exchanger to affect the temperature of a separate closed freshwater loop running through the floor. This second loop contains 40 miles of plastic pipe moving over 73,000 gallons per hour to change the temperature of the space. Less overhead ducts were required as a result.

All new windows use high performance triple element glazing to better insulate the building and admit copious amounts of natural light, further reducing reliance on electricity. Sixteen per cent of roof run-off is captured in cisterns and sterilised prior to flushing toilets. What isn’t stored is filtered and returned to the bay.

What was the state of the original pier structure?
The substructure of the pier was heavily damaged in the Loma Prieta earthquake of 1989. Our design combined repairs to existing pilings with insertion of new mega piles at the four corners. These were connected by a new structural slab poured over the existing floor that knits it together, creating a stiff platform that can withstand major temors. This allowed us to repair just over a third of the existing 15,000 piles.

A service lot that had been built in the 1950s to conjoin the piers was removed to create the new plaza. Pilings were left to mark tide movement and serve as anchorage for temporary exhibits.

Seismic bracing was inserted into the transit shed. The structure is painted a uniform color to maximise light reflectance and minimise glare, but also to allow it to recede from view. The new structure is fabricated using round pipe to differentiate it from the old structure. Structure is celebrated but never steals the show.

What is your favourite part of the new building?
The Fisher Bay Observatory, the only new structure, is an elegant two-story steel pavilion at the end of Pier 15 that contains an open plaza designed in collaboration with landscape architect Gary Strang.

The Observatory stands out with its taut façade. The building uses fritted glass to mitigate heat gain and reduce bird strikes, and houses the Seaglass Restaurant and the ticketed Fisher Bay Observatory Gal- lery, which offers views of the open water, maritime traffic, Treasure Island and Bay Bridge, as well as surrounding landscape.

What were the biggest challenges?
Balancing the environmental needs and historic stewardship was a challenge. The more you err toward the historic, the more you sacrifice energy-efficiency, whereas the most energy-efficient designs lose the history and uniqueness of a place. Our design strikes a balance.

What drew you to a career in architecture?
When I was a child I drew voraciously, liked making things and could lose myself for hours. My mother often had to pry me away from my creations.

How did you start your career?
My first degree in architecture was at the University of Michigan. I then worked for four years in Dallas, Austin and New York City prior to my graduate degree at Yale. My early mentors were Alan Buchsbaum and Frederic Schwartz. Fred remains a trusted friend, confidant and collaborator.