Being honored with the highest level of Leadership in Energy and Environmental Design (LEED) Platnium is rare enough, but now one California establishment and garnered two of the prestigious certifications. The California Academy of Sciences announced that it had been named the world’s largest Double Platinum building.

The California Academy of Sciences opened in San Francisco on September 2008. The museum features innovative designs like a living roof (pictured below) and insulation made with recycled denim. One month after opening, the museum earned a LEED Platinum award for new construction. Most recently, the museum earned a second LEED Platinum award specific to existing buildings in the operations & maintenance category.

image via Shutterstock

What that means is the day-to-day operations of  the museum meet the highest standards of sustainability. Specifically, the U.S. Green Building Council, who hands out such awards, looked at the building’s purchasing decisions, recycling and composting rates and even at what kind of transportation staff members take to get to work.

The designation marks the museum as the only one to earn the Double Platinum designation. The museum includes an aquarium, planetarium, natural history museum and educational programs. More than 5 million visitors have explored the museum since its opening three years ago.