Madrid Architecture school canteen
To step into the university cafeteria in Madrid was like hitting a wall of cacaphony. After the installation of acoustic panels, the perceived sound level has been halved. ”It´s something exceptional” says Agustina Ramos, employee of the cafeteria.
The Superior Technical School of Architecture of Madrid is internationally renowned within architecture and considered not only one of the best in Spain, but one of the best architectural schools in the world. At the university 5 000 students, 400 teachers and 100 employees meet everyday. Here are future architects meeting the reality of many pupils and teachers around the world: the effect of insufficient soundproofing.
Before the installation of acoustic panels, the situation was unbearable.
Within the activities of the university a research project has been conducted together with Saint-Gobain Ecophon. It consists of the acoustic treatment of both the students’ and teachers’ cafeteria. Given the need for acoustic treatment in the cafeteria, a series of acoustical measurements was made. Previously, acoustical qualities such as reverberation time were determined. To improve the sound comfort acoustic panels were installed, covering 50 percent of the ceiling surface.
Before the installation of acoustic panels, the situation was unbearable, not least for the employees that had to work in the both cafeterias. The students and teachers at least had the alternative to eat elsewhere.
Some testimonies from before the installation
”In the peak hours here, you don´t hear anything. People talk to you, and you don´t know where it comes from. Many times I think I´m going deaf, because I don´t understand. I think my colleagues feel the same way, because the noise is horrendous, especially at peak hours”, says Agustina Ramos, employee of the cafeteria.
”Regarding the noise in the cafeteria, it´s a pretty hectic environment where you hardly can speak to your friends. You have to scream, and my friends and I seldom eat here, we usually eat next to our school lockers. If you want to rest or relax or simply have a nice conversation while eating, you can´t”, says student Gabriela Vieira.
”Regarding the atmosphere in the cafeteria I think it´s ok, but there is too much noise, a lot of stress. That´s why many times we try to go outside or eat at home, to avoid it”, says student Antonio Soriano.
A stunning end result
The difference after the installation of acoustic panels is stunning. The cacaphony has been converted into a soft buzz that enables conversations at a normal speech level. The so called Lombard effect, that we raise our voice when the surrounding noise is strong, is minimised.
The result has been extraordinary, and the proof of that is the satisfaction shown by the users.
Some testimonies from after the installation
”The truth is that since they put this on the ceiling, things are a lot better. It's more cozy, and there are less voices. I think it's something exceptional – it´s outstanding”, says Agustina Ramos.
Student Arantza Uriarte eats in the cafeteria almost all weekdays: ”The change is really noticeable. Before it was unbearable to eat here. You had to leave as soon as you were ready, because you couldn´t hear your conversation. Now it´s much nicer and you can spend more time here”.
The principle on the Architectural College, Louis Maldonado, is very satisfied with the outcome of the research project. ”The result has been extraordinary, and the proof of that is the satisfaction shown by the users of the space in comparison to before”.
Now students can have conversations
Dr César Díaz is a teacher in acoustics at the Architectural College. He explains the perceived improvement with dropped reverberation time and sound pressure level.
”With the conditioning made of the ceiling of the cafeterias, the reverberation time has dropped significantly in the space. Now it's below one second in the mid-frequencies. As a consequence the sound pressure level has dropped in a very notable way. Now students can have conversations with their friends around the table at a distance of two meters without the need to raise their voices.”
Results of the research project
- The reverberation time was reduced from 2.3 to 0.8 seconds.
- The equivalent sound pressure level was reduced from 75 dB to 69 dB.
- When measuring before the installation, levels exceeded 80 dB at peak hours. Levels continuously higher than 80 dB require a preventive action.
- Before the intervention, the noise was perceived as 50 percent higher.
- The Spanish Building Code recommends a reverberation time of less than (<) 0.9 seconds in eating spaces.
Text: Lars Wirtén
Photo: Alvaro San Román Gómez