In 2006, CBC broke ground on an expansion to its downtown Vancouver broadcast centre. The building had originally opened in 1975 and was nicknamed “the bunker” for its concrete-heavy architecture and lack of windows. To balance its earlier industrial leanings and connect more with the community, CBC chose a design that features an open newsroom with plenty of natural light, courtesy of the addition’s many windows.
BKL was hired to design the acoustics for the expanded newsroom, including the broadcast studio that overlooks busy West Georgia Street. BKL also assessed construction noise and provided recommendations on how to best mitigate this noise during news and radio broadcasts, which would continue during renovations.
Acoustical Challenges: Construction Noise
While the expansion was built, television and radio production continued in the existing wing.
But before shovels hit the ground, BKL assessed how construction noise would impact television and radio broadcasts by obtaining real-world data: Acousticians placed instruments in critical areas of the building and measured the transmission of sound from controlled examples of typical construction operations—jackhammering, demolition, dropped loads, etc.
At the same time, these field trials gave CBC real-life examples of how construction noise would affect its work; this allowed CBC to plan for the possible disruptions to their broadcast operations.
BKL met with the stakeholders to explore various mitigation scenarios, and establish project-specific limits for intruding noise levels. After the assessment, the project team implemented many of BKL’s recommended solutions, building additional walls to shield sensitive TV studio areas, cutting concrete slabs to prevent structure-borne noise transmission, and creating a detailed schedule of construction and production activities to minimize disruption.
Acoustical Challenges: Broadcast Studio Design
After assessing and providing recommendations to mitigate construction noise, BKL turned its focus to designing the acoustics for the new studio space. One issue was noise from traffic and emergency vehicles intruding into the proposed radio studios and integrated newsroom. The other major concern was controlling noise from renovated and new HVAC and exhaust systems. From this point forward everything became business as usual: meeting with the design team, designing and analyzing the acoustics in-house, writing reports, and reviewing shop drawings. BKL also visited the site to conduct field reviews to confirm the effectiveness of its recommendations.
Thanks to BKL’s recommendations for limiting disruptive construction noise, CBC continued broadcasting while the expansion was built. For example, the contractor built a temporary wall around the Canada Now studio to allow for normal operations.
For the acoustical design component of the project, BKL specified the sound isolation requirements for the building envelope around the newsroom and the radio studios along West Georgia Street. Before installation, a sample of the glazing used for the curtain wall was sent for testing to the acoustical laboratory at University of Alberta to confirm its sound isolation performance.
To control noise transmission from the HVAC system to the TV and radio studios, BKL recommended silencers, which were installed with excellent results.
To control reverberation, BKL recommended that sound absorptive treatment be installed in the newsroom, radio suites, and editing rooms. According to follow-up measurements, this treatment successfully limited reverberation and reduced overall noise levels in these noise-sensitive areas.