Acoustic ceilings reduce teacher stress

Negative stress leads to bad decisions and poorer performance. When we are under stress, our heart rate increases, which is a good measure of how stressed we are.

Jana Dolejší, a lecturer at the VSTE university of technology in České Budějovice, supervised the research project conducted by four engineering students for their bachelor’s thesis. She describes how the students engineered better acoustics by installing high-performance acoustic ceilings in one classroom at each of their selected schools. They based their calculations and requirements on Czech recommendations, which are broadly comparable to German DIN standards.

Clear indication

The students measured the reverberation time and other acoustic parameters before and after the improvements to each classroom. With the help of one of the teachers, Dolejší measured the heart rates of the teaching staff over the course of a day.

“The study provides a clear indication of a correlation between room acoustics and heart rate,” she reports. “Teachers’ heart rates were higher in classrooms that had not been acoustically improved.”

Dolejší emphasizes that measuring heart rates for one day is not long enough to be able to draw any scientific conclusions.

“However, the findings are so interesting that the university now wants to perform a more detailed study, looking at multiple classrooms and teachers over a longer period of time.”

Improvements have dual effect

As part of their research, the students interviewed the teachers, asking them to describe their subjective perception of the improved acoustics. The outcome was clear.

“All the teachers who took part in the study want to carry on teaching in the acoustically improved classrooms.”

“Acoustic improvements of this kind have a dual effect,” explains Dolejší. Besides slowing our heart rate and improving our overall experience, the better acoustics created by the new ceiling cause us to automatically lower our voices. Pupils also talk less when they are not supposed to, which in turn improves the learning environment.

Old schools with high ceilings

Better acoustics are sorely needed in many of the Czech Republic’s school buildings.

“A lot of the schools are old, with ceilings up to four metres high and absolutely no noise abatement measures. No-one is checking the acoustics in these schools, since there is no requirement to improve them.”

The old schools have big classrooms, often as large as 70 square metres, designed solely for frontal teaching. With ceiling heights of three to four metres and no acoustic treatment of any kind, the acoustics are very poor.

“The problem is that education managers and head teachers are often unaware of the solutions available. And cost is the driving factor in renovation projects. Many architects have told me that they have zero budget for acoustics.”

Improving situation

“Nevertheless, the situation is better than it was a few years ago,” adds Dolejší. She now receives many requests to carry out acoustic measurements in schools, and compliance with Czech standards is mandatory for all new school buildings.

“When a new school is built, the acoustics have to be calculated and measured. The problem is that no-one calculates and measures the acoustics in our old schools.”

Text: Lars Wirtén
Photo: Štěpán Látal and Rickard Johnsson, Studio-e.se