Acoustic Test Data and Why It Matters
Test data is without a doubt a very important factor during the process of any building construction. In one of our previous articles regarding acoustic underlays, we discussed in detail how acoustic test data is gathered.
To quickly summarize, there are two main methods of gathering data. First method is testing within a laboratory, where a tapping machine is used and a microphone is then installed to gather and measure the sound and vibration coming from the machine. This method is reliable because it is conducted in a controlled environment where all the measurements of the sound and vibration gathered are solely from the tapping machine and not affected by any external factors. The second method is testing in a specific building, often a completely finished one. This is useful to test if this specific building meets the acoustic requirements.
STC, IIC, and Delta IIC are ratings that measure different aspects of acoustic performance. STC stands for Sound Transmission Class, which measures the airborne sounds that travel through the air. Examples of this is people talking or loud music. IIC stands for Impact Insulation Class, which measures the impact noise that travels through ceilings and walls. Examples of this include footsteps, children dropping toys, or dropping of gym weights. Delta IIC measures what a specific acoustic product has in effect in terms of impact isolation performance once installed. To summarize, it is the difference between the building with the product installed minus the building without the product installed.
So why does all this matter?
Sure it matters, and it seems to be obvious, we hope!
Test data is key for both contractors and acoustic companies to determine the final solution on what needs to be done for a specific construction project. In one of our many past projects, test data played a huge role for both us and our client in the overall success of the project. The project was a luxurious high rise residential building located in a promising area in Beijing, China. The project had a relatively higher acoustic requirement than other residential buildings we have worked on, with the rating requirement of IIC 58. To determine the best solution, testing came in to play big time.
1. Meeting Acoustic Requirements
As we just mentioned, one of our projects located in Beijing, China had a higher requirement to meet than others. Every project has their own requirements, and test data is important to determine if the planned buildup along with our acoustic product installed would meet said requirement.
We recreated the buildup with GenieMat FF installed in one of our test labs. In this well controlled environment, an accurate reading was possible and accurate data results were produced. With this, we were able to determine that the product was a success for this project.
2. Buildup Comparisons
Test data also allows both the acoustic companies and the contractors to determine the best solution through comparisons. Generally speaking, acoustic companies will present various different possible buildups with different acoustic products used, which would show different ratings and thicknesses of the entire buildup.
Like this residential project we had in Beijing, we presented a variety of solutions with different test data, and from there we discussed together which thickness of the underlayment was most ideal for the project; one that would successfully meet the requirements and at the same time minimize their expenses to fit with the overall project budget.
3. Materials To Be Used
Another insight we can get from test data is the materials required for the project. Once the acoustic company presents the data which shows various buildups to the contractors, part of the factor that affects the final decision is the materials that would need to be used. Some buildups that meet the same acoustic requirements may sometimes require different or even more materials, which can affect the overall budget and possibly the logistic side of things.
So Test Data Is Important, But How Hard Is It To Get?
This can really depend. Acoustic companies or contractors may sometimes outsource 3rd party labs to conduct the experiments to determine the ratings, but this may come at a higher cost that can affect the budget of the construction project. Test reports of past buildups are often not convenient to access and most likely come with a price.
Pliteq understood that this is a challenge that many face, and that is why Pliteq EchoOne is created. We want to provide a huge source open to our members and anyone else who want to register, with free access to over 700 test reports for engineers and acoustic consultants. Test reports cover an extremely wide range of different buildups and projects in the past, which can all be used as great reference points for up and coming construction projects.