School Gymnasium Acoustics - Part 4

Stage 3: Installation of 90% of panels

Encouraged by the initial results Stan and his helpers then installed panels on all the upper walls of the Gym (except the top section at both ends which will be completed in the next school holidays).

A third reading was then completed by GB Acoustics and the results were a dramatic reduction in reverberation times from 3.00 seconds to 1.8 seconds as shown below:

Now the difference was much more noticeable and as the head of Physical Education, Mr James Dean commented

“all sounds are now much softer and it is far easier to teach Gym classes when you can move from group to group and not have to raise your voice to be heard”

The other challenge overcome by Stan and his team during this stage of the project was the attachment of the panels to the walls. After several tests, it was found that the best solution was a specialised polyester panel contact glue called Cantac which is available in a 13.7 kg canister with an application spray gun and hose. On plasterboard walls only the panels need glue applied however in this case the wooden Gym walls had been coated with Polyurethane and the Cantac glue had to be applied to both the panel and the wall and then positioned and pressed to the wall by hand and using a scissor hoist. Stan comments: “using two canisters and spray guns the installation could be completed in half the time”.

Conclusions & Next Steps

Stan and his team have installed 730 Polyester Acoustic Panels and the project has been a highly successful project to date. NZ Acoustics and RNLS staff expect that once the last stage (remaining 82 panels) is completed during the next school holidays then they will have achieved their target reverberation time of 1.5 seconds.

The project has been completed for under $20,000 NZD – a fifth of the alternatives quoted.