The Tower at PNC Plaza
Architect – Gensler
Interior Designer – Jensen Hughes
Landscape – LaQuatra Bonci Associates
Sustainability – Paladino
Vertical Transportation – Edgett Williams Consulting Group
Civil – Civil & Environmental Consultants Inc.
General Contractor – PJ Dick
Lighting – Studio I, Fisher Marantz Stone
Traffic – Trans Associates
MEP and Structures – Buro Happold
Gensler is a well-known global architecture firm that strives to promote diversity, resilience, and well-being for everyone. The firm’s sustainable measures include approximately 50 locations in Asia, Europe, the Middle East, Australia, and the United States of America.
The Tower at PNC Plaza, which opened in October 2015, is a new milestone in PNC’s efforts to revitalize downtown Pittsburgh. Gensler and its partners established a new bar for sustainable skyscrapers while developing this new 32-story corporate headquarters, inventing a revolutionary, low-energy heating and cooling method. The LEED Platinum-certified skyscraper pushes building performance to new heights with its unique, permeable double skin and creative workplace approach. The landmark skyscraper improves the science of high-rise office buildings, brings new advantages to the workplace, and helps the city as a whole through an integrated approach.
Project Goals and Aspirations | PNC Plaza
PNC embraced three central goals that drove The Tower’s design.
Energy Responders
- 50% reduction in energy use compared to a typical office building (2007 version of the ASHRAE 90.1 standard)
- 77% reduction in portable water use achieved through advanced treatment and recycling systems.
- The tower raises the bar for sustainable development, encouraging others to follow.
Workplace Innovator | PNC Plaza
- Custom-designed workstations with stilted-legged seating and privacy screens allow air to circulate while low above-desk partitions allow in natural light.
- Operable doors, localized thermostats, and automated blinds allow employees to adjust light, air and temperature in their work areas.
Community Builder
- The Tower at PNC Plaza is a catalyst for renewed Investment in downtown Pittsburgh.
- The open, transparent lobby creates an “urban room” and engages the surrounding streets and neighbourhood.
- The Tower’s form and overall transparency-made possible by the building’s innovative systems underscores a sense of connection with the city.
- The building’s water treatment and recycling system diverts the majority of The Tower’s storm and wastewater from Pittsburgh’s sewer system, reducing its impact on the city’s infrastructure.
- On the 28th floor, a five-story-high, column-free Indoor Park offers a place for respite amidst expansive city views.
Double Skin Facade | PNC Plaza
The Tower advances within the United States by utilizing one-of-a-kind types of double-pores and skin facade assembly to wrap more than 90% of the building. It is currently the most convenient fully-automatic double-pores and skin facade in the country. The structure is enclosed in a double wall that compresses and expands under unique situations.
- The movable twin pores and skin facade define a 30-inch-wide hollow area that insulates the building and aids in herbal ventilation. “Popper” home windows within the exterior skin and “flopper” vents within the interior skin open mechanically to allow fresh air in.
- The operable double pores and skin veneer define a 30-inch-wide hollow area that insulates the building and allows for herbal ventilation.
- “Popper” home windows within the exterior skin and “flopper” vents within the interior skin open mechanically to allow fresh air in.
- Different sections of the construction are insulated by a “thin” double-pores and skin facade with a miles narrower hollow space.
- Different sections of the construction are insulated by a “thin” double-pores and skin facade with a miles narrower hollow space.
- Blinds placed between the two window barriers reduce glare and heat gain while not shutting out daylight or views to the outside.
The Solar Chimney
The sun chimney, composed of vertical shafts within the building core and crowned by a 5,000 rectangular foot glass field directed southerly in the direction of the sun, enables warmth and ventilates The Tower with minimal energy.
On hot days, the solar chimney generates a draw, drawing dazzling air in by the movable facade, up via the shafts, and out via the pinnacle, providing natural air movement without the use of mechanical fans. During cooler weather, the skylight field warms the air before it is brought into the structure. The Tower is one of the first high-rise buildings in the United States to include a solar chimney. The solar chimney and moveable double-skin facade paintings work together to warm, cool, and ventilate the tower.
Natural Ventilation: When the outside conditions are optimum, which is regularly in the spring and fall, all of the poppers and floppers open to allow fresh air into the occupied regions.
Cooling: In hot temperatures, the poppers open while the floppers remain closed. This allows sparkling air to enter and vibrate the space, assisting in the maintenance of indoor temperature.
Active Systems
To ensure the best interior comfort with low energy use, these passive design solutions operate in concert with active technologies such as dual-wheel energy recovery air handlers, high-efficiency condensing boilers and chillers, and an efficient dual-temperature chilled-water system.
Active chilled beams on office floors circulate a combination of fresh air and warm room air over a chilled coil to cool and ventilate the space while using the least amount of energy. Water flows through the chilled beams, cooling the surrounding air and causing a convection cycle in which cold air falls and hot air rises and is cooled by the beams.
Structural Systems | PNC Plaza
The cantilevered structural slabs provide unimpeded views in the northwest and southeast corners. The two-story, column-free collaboration areas along the western facade are supported by a long-span steel structure.
An efficient steel framework structure braces roof columns along the perimeter and supports the solar chimney’s suspended, slanted concrete slab and glass skylight. A 100-foot-long curving steel truss supports the five-story 28th-floor atrium and suspends the cable-net enclosure. The use of lightweight concrete minimizes column loads and the number of structural elements needed. The building’s top 100 feet are perforated to lessen the structural resistance required for wind loading.
Locally sourced/ Recycled Materials
Structural steel and rebar have 35-60% recycled content and were manufactured within 500 miles of the project site, lowering transportation-related carbon emissions. The concrete mix contains 25% fly ash and employs locally sourced aggregates and sand.
Embodied Carbon and Energy Analysis
These design solutions lowered the embodied energy of the structure by 68% and the embodied carbon by 71%.
Water Strategy | PNC Plaza
When compared to a conventional building, a sophisticated water treatment system that includes membrane ultra-filtration, carbon filtering, and ozone disinfection has the potential to save 77% on water use. Treated water is utilized to flush toilets, supply the cooling system, and irrigate the landscape, saving 4.5 million gallons of potable water per year and practically eliminating discharge to city sewage.
References:;
Buro HappoldFollow this publisher – current follower count:173 (2015) Burohappold engineering the tower at PNC Plaza Case Study, Issuu. Available at: https://issuu.com/burohappold/docs/bh-pnc-tower-case-study-_pageturnin (Accessed: October 18, 2022).
