When Sempra Energy began drawing up plans for its new $165 million corporate headquarters in downtown San Diego, acoustics was top of mind for the design team charged with meeting specific criteria for noise levels inside the 16-story LEED Gold-certified office building.
Those criteria required that San Diego design firm Carrier Johnson + CULTURE specify acoustical ceilings that would absorb noise in the open-plan offices and prevent noise from private offices and conference rooms from being heard in adjacent spaces.
To meet the noise level criteria for the open plan offices, the design team needed an acoustical ceiling with a Noise Reduction Coefficient (NRC) of at least 0.70, meaning it absorbs 70% of the sound that strikes it. In the adjacent private offices and conference rooms, where speech privacy is important, a Ceiling Attenuation Class (CAC) of at least 35 was needed to effectively block sound from traveling across the plenum into adjacent spaces.
Total Acoustics Performance
The design team satisfied both requirements by selecting Ultima® ceiling panels from Armstrong® Ceiling Solutions for all the office spaces in the nearly 400,000-sf building. The panels feature new Total Acoustics™ performance, which is the ability to provide both sound absorption (NRC) and sound blocking (CAC) in the same panel.
Armstrong Ultima® ceiling panels offer sound absorption and sound blocking in a single panel.
“The NRC was very important in the open-office areas,” says lead interior designer Stuart Fromson. “By utilizing very low furniture partition system heights, we are providing daylight and views to 70% of the building occupants. This creates a very open environment, so we were looking to make the acoustics as pleasant as possible in this area.”
In the private offices, the CAC helps prevent private conversations from being overheard in adjacent offices that share a common plenum. “That’s why it was important to have CAC in the ceiling of the new building,” says Fromson. “It’s critical that we don’t get sound transfer over the top of the walls.”
Flexible Spaces
A demountable wall system with a flush Armstrong Silhouette® XL® suspension system provides the design flexibility needed to reconfigure the offices spaces when needed. “With high NRC and CAC in one panel, we can move walls as needed to make private offices into open spaces and open spaces into private offices, and still maintain the sound blocking and sound absorption we need for each space,” he explains.
The Armstrong ceiling system forms one leg of a three-part acoustic control solution. The other components include an active sound-masking system embedded in the ceiling and a wall system that includes dual glass paneling for extra sound suppression.
“Employees really like the space,” adds Fromson. “I was in their elevator one day with an employee who was talking about the new building, and I mentioned I was a lead designer. The employee just raved on and on about how happy they were with the acoustics in the space. As a designer, that’s what you want to hear.”
For more information about Total Acoustics™ ceiling panels, visit armstrongceilings.com/totalacoustics.