Ceiling Clouds

Hi Eri Unfortunately, it's not as easy as being able to count the cloud areas twice. There is an increased performance benefit, but you will need to calculate the reverberation time of the space to meet the LEED requirement that way, instead of going the square footage of treatment route. What will happen with the clouds is that the absorption coefficients behind the NRC value will increase. The only way to appropriately represent this is by calculating reverb time using the improved absorption coefficients.

You would use the ANSI calculation path, but you would use improved/revised absorption coefficients for the panels to take into account the open sides of the clouds. These would need to come from the manufacturer or estimated based on a similar product. Armstrong, for example, sells a cloud product called Soundscapes that uses their NRC 0.9 ceiling tile and publishes acoustic data. Doubling the panel area would not be the correct way to do the calculation.