Office building lobby design has gone largely unchanged over the decades. And, for the most part, it’s still unexciting. That is, unless you’re a big fan of terrazzo flooring, the occasional water feature and the soothing smooth jazz stylings of Kenny G.

Pompous yet perfectly bland with an eye toward efficiency and security, the design of commercial high-rise lobbies is dually concentrated on first impressions and the movement of human traffic — that is, how to move throngs of office workers and visitors from entryway to elevator bank through these cavernous spaces in the smoothest, fastest and least distracting way possible.

Yet many office towers, both newly built and newly remodeled, are changing the way we interact with their lobbies, elevating these oft-unloved spaces from sterile, soulless entrance halls into vibrant social hubs with attention-grabbing features ranging from humidifying glass panel waterfalls to natural light-strewn lounges areas to air-scrubbing hydroponic gardens that soar 100 feet into the air. Disappearing are the days when office building lobbies were simply places that one passed through en route to somewhere else ... they're now places for lingering, interacting, engaging.

And then there’s the newly completed Tower at PNC Plaza.

The Beacon, an interactive LED light installation at Pittsburgh's PNC Tower that communicates building performance and other data Photo: Andy Ryan

Soaring 33 stories above downtown Pittsburgh and built to use half the energy consumed by typical office buildings, this LEED Platinum-exceeding glass and steel edifice, complete with double-skin façade and solar chimney, has been heralded as the greenest skyscraper ever completed. (Seattle’s six-story Bullitt Center still likely rules when it comes to green commercial buildings.)

And as for the Tower at PNC Plaza's main lobby, it's one high-rise lobby that can never, ever be accused of being soulless.

After all, the very soul of this living, literally breathing building is on full public display in the lobby itself. Said soul takes the form of a 24-foot chandelier-cum-interactive media installation that harnesses light and sound to reflect what's going on inside — and outside — the tower from an operations standpoint.

Functioning as one part artwork, one part audio-visual educational tool, the Beacon communicates intangible and oft-inscrutable building performance data (energy consumption, water recycling, sun exposure, natural ventilation, waste diversion and even composting) to the public in real-time through a mesmerizing display of constantly shifting LED rings and subtle sounds. Simply put, “the source for the Beacon’s visualizations is the Tower itself.”

While a majority of passersby may be prompted to stop and admire the kaleidoscopic light fixture dangling from the Gensler-designed high-rise's lobby atrium, not everyone will stop to try and figure out what it all means. For curious types who do pause to engage with the installation, tablets are available in the Tower lobby for public use. From the tablets (or any personal digital device), the public can access a custom interactive website developed by PNC that explains exactly how the building is working to save resources — and how this is all signified through light and sound.

The Beacon, an interactive LED light installation at Pittsburgh's PNC Tower that communicates building performance and other dataPhoto: Andy Ryan

No stranger to adding a bit of rubbernecking oomph to otherwise unexceptional office towers, ESI Design — the New York-based “innovation and experience” design firm was founded by interactive designer Edwin Schlossberg, husband of Caroline Kennedy — conceived and executed the installation.

Explains Gideon d’Arcangelo, VP of Creative Design for the lauded firm: “Our goal in designing The Beacon for The Tower at PNC Plaza was to transform the way people experience the building — and communicate the many invisible things the building is doing, behind the scenes, to maximize resources. The Beacon is a dynamic, data-driven media installation that is intriguing and beautiful to look at and hear. It also rewards the curious, by explaining itself and encouraging people to dig deeper to learn how the building works and how it is performing at any given moment.”

The Beacon itself is composed of 1,584 LED-backed liquid crystal polycarbonate panels, arranged 48 vertical high and 32 across (one row for each floor of the building) to create what ESI calls a “striking and unique media canvas.” As the firm explains, the installation “displays focus on 5 key modes that generate interpretive expressions related to sunlight, energy, water and recycling, ventilation and more.” Meteorological data from the PNC Tower’s weather station is also visualized in the Beacon so that cooped-up office workers passing through the lobby will now what they're in for before stepping outside.

And, as PNC explains, the installation itself is, go figure, super-efficient:

Each panel has liquid crystal film that becomes clear when it receives electricity, or opaque without it. Inside is a grid of 8 LEDs that show a range of colors. These elements can be used simultaneously or separately to create animations with a variety of color, motion, and diffusion. The liquid crystal film draws no energy when opaque and uses very little when transparent, while LEDs use less energy than incandescents, making the Beacon highly energy-efficient.

While the lobby of a sparkling new $400 million office tower — or "skyrise" as PNC calls it — belonging to the fifth largest bank in the United States (by number of branches) may not be a big draw for most food- and funicular-driven Pittsburgh tourists, it’s sure to be appreciated by both PNC employees (the Tower at PNC Center will ultimately be home to 2,200 of them) and residents of a city that’s emerged as a hotbed of innovative green building.

PNC can be partially credited for the flurry of superlative green building projects in Pittsburgh.

Founded in 1845 as the Pittsburgh Savings and Trust Company, the financial services behemoth boasts more than 200 LEED-certified buildings nationwide including more new-build LEED-certified projects than any other company. When it opened in 2007 on the site of an abandoned railroad yard, the 647,000-square-foot PNC Firstside Center was the largest LEED certified project not just in Pittsburgh but in the entire world. Just a few blocks away, PNC's LEED Gold-achieving renovation of the old Mellon National Bank Building melds historic preservation with advanced green building technology.

And having nothing to do with PNC, the LEED Platinum-certified Center for Sustainable Landscapes at the Phipps Conservatory & Botanical Gardens is ranked amongst the greenest buildings on the planet while the the Children's Museum of Pittsburgh was the nation's largest LEED Silver-certified museum when completed in 2006. What's more, Rafael Vinoly's redesign of the David L. Lawrence Convention Center was awarded LEED Gold in 2003 making it the first convention center in North America to achieve LEED-dom. Pittsburgh is also home to the nation's first LEED certified food bank, college dormitory and radio station.

Outside of the "funky-looking lobby chandelier that doubles as a building monitor," the Post-Gazette offers a decent overview of the Tower at PNC Plaza's other standout features including an indoor park on the 28th floor with "five stories of glass held together by cables and planters with recycling bins at each end."

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