Sustainable design and LEED requirements are transforming the building industry. But like any shift in practice, there’s a domino effect. A number of sustainable design options that earn a building IEQ credits (indoor environmental quality) in some respects are at odds with achieving equally important acoustical goals. With creative engineering and an integrated design approach, these inherent conflicts can be resolved.
The LEED checklist of desirable features includes natural ventilation, thermal comfort and the use of recycled/low VOC finish materials, and these are all areas where “credit conflicts” frequently show up when it comes to also satisfying acoustical criteria. Speech privacy and sound isolation are challenging to achieve in a naturally ventilated building. On a noisy site, open windows let in street noise – buses, trains and auto traffic generate 69-75 dB, well in excess of the recommended 45 dB. In a quiet area, naturally ventilated buildings can be too quiet for speech privacy, lacking the background white noise of HVAC systems. Hard surfaces bounce sound while they reflect light.