But seriously, what is it with Pennsylvania botanical gardens garnering not-necessarily-horticulture-related superlatives?

Late last year, it was the subterranean, vegetated wall-wrapped lavatories at Longwood Gardens outside of Philadelphia being called America’s number one place to go number one.

Now, the Center for Sustainable Landscapes (CSL), a research- and education-dedicated facility at Pittsburgh’s famed Phipps Conservatory and Botanical Gardens, has been named as one of the greenest buildings on Earth.

Completed at the end of 2012, the CSL, conveniently located at the most scenic place in Pittsburgh to walk off a Primanti Bros. lunch, is indeed one seriously deep green building with a quartet of well-deserved credentials — “the planet’s highest sustainable building certifications” per the copywriters at Phipps — to back it up.

First off, the CSL is LEED Platinum certified — and it's not the first building at Phipps, an institution that first opened its doors in 1893, to achieve LEED-dom. The gorgeous, glass-domed Welcome Center was awarded with LEED Silver certification back in 2006. In 2012, Phipps’ 36,000-square-foot Production Greenhouse became the first building in the world to achieve LEED Platinum for Existing Buildings: Operations and Maintenance. According to Phipps, the CSL is tied for the top number of points ever awarded under version 2.2 of the US Green Building Council’s rating system.

The CSL has also achieved two lesser-known certifications. Simultaneous with its LEED Platinum certification in 2013, the building received a rare four-star rating from the Sustainable Sites Initiative (SITES), a landscaping-oriented certification system developed by the United States Botanical Garden, The Lady Bird Johnson Wildflower Center and the American Society of Landscape Architects. To date, 45 other projects across the country — a motley mix of parks, commercial and institutional spaces, mixed-use developments, and private residences — have participated in SITES on a pilot basis.

Additionally, CSL is the first (and only) building to achieve WELL Platinum certification, a standard established by the WELL Building Institute that focuses on a structure’s impact on human health.

The Center for Sustainable Landscape at Phipps Conservatory and Botanical Gardens, Pittsburgh

Spread out across over 2.9 acres, the CSL is located on a once-polluted brownfield site. (Photo: Denmarsh Photography, Inc.)

The Center for Sustainable Landscape at Phipps Conservatory and Botanical Gardens, Pittsburgh

CSL's green roof reduces stormwater runoff and provides for one gorgeous al fresco event space. (Photo: Denmarsh Photography, Inc.)

And then there’s the performance-based icing on the cake.

In early March it was announced that after 12 months of testing, the CSL has officially met the rigorous criteria set forth by the Living Building Challenge — aka the holy grail of green building standards.

I’ve previously profiled featured past Living Building Challenge recipients to achieve full “Living” status — with the addition of the CSL there are now only seven in total — including Smith College’s Bechtel Environmental Classroom and McGilvra Place Park in Seattle. The latter is located adjacent to the Bullitt Center, a deep green commercial building that’s also pursuing Living Building Challenge certification. This would only make sense given that the LBC’s parent organization, the International Living Future Institute, is one of the nearly two-year-old Bullitt Center’s primary tenants.

There’s a lot to discuss when it comes to how exactly the CSL — ringing in at about 22,000-square-feet, the structure was built on a former brownfield site— went about achieving these incredibly tough certifications, particularly the Living Building Challenge.

For starters, the super-insulated, green roof-topped building is net-zero energy, producing more energy annually than it consumes thanks to a 125-kw solar array, geothermal wells, a vertical-axis wind turbine (the first in Pittsburgh) and various passive heating/cooling/lighting strategies. Water is given extra-special treatment at CSL — that is, all wastewater is treated sans chemicals and recycled on-site helping the building to achieve net-zero water status. Rainwater is harvested and stored in 80,000-gallon underground tanks.

In terms of materials, often the trickiest aspect of the Living Building Challenge, the CSL was built from 10 percent salvaged materials and 30 percent recycled materials. Eighty-two percent of all materials used in the project were regionally sourced within a 500-mile radius of Phipps’ location at Schenley Park in Pittsburgh’s East End. All materials used in the building of the CSL are eco-friendly and toxin-free to support superior indoor air quality.

The Center for Sustainable Landscape at Phipps Conservatory and Botanical Gardens, Pittsburgh

The passively cooled atrium features a Green Gallery showcasing nature-inspired art. (Photo: Denmarsh Photography, Inc.)

Of all the “petal” categories that comprise the Living Building Challenge, the Beauty/Inspiration category is perhaps the most fun. Writes Phipps: “Beyond the delight this beautiful building inspires in the beholder, the CSL is a symbol of hope for generations to come, providing a glimpse of the harmonious future within our grasp and operating as an important catalyst for change.” That being said, the CSL, which is also home to an extensive biophilic art collection, functions as a living laboratory of sorts that the public is free to explore during docent-led tours.

A lot more nuts and bolts (Bioswales! Dessicant wheels! Solar Distillation Systems! Brise-soleil screens!) work together to make the Center for Sustainable Landscapes — designed by Pittsburgh-based Design Alliance Architects, by the way —such an uber-green accomplishment. One could write a rather hefty book about all the different aspects of the project. Wait ... it's already been done.

The folks at Phipps are rightfully proud of what they’ve created and are more than happy to educate others about how they did it. The CSL, located directly behind the sprawling conservatory complex, may not get as much public foot traffic as, let’s say, the Tropical Forest Conservatory, the bonsai collection or the orchid room. Still it's well worth the detour for anyone interested in experiencing a truly cutting-edge building where both flora and the future are top considerations.

Related on MNN:

Matt Hickman ( @mattyhick ) writes about design, architecture and the intersection between the natural world and the built environment.