No more confused sounds, words that are difficult to understand, or shows and events penalized by bad acoustics: as of this summer the Ex Enaoli Church in Rispescia, part of the ”Il Girasole” National Centre for the Sustainable Development of Legambiente, will become the spearhead of the projects for acoustic upgrading with recycled rubber. Ecopneus, in collaboration with Legambiente, entrusted Vie en.ro.se. Engineering with the contract for the church’s acoustic correction project, which was then realized thanks to the work of the companies Aetolia, B-Beng, Blumohito and Dife.
The acoustics issue
The church has a volume of approximately 1300 m3 and is characterized by very smooth and reflective finishing materials (marble floors, plastered walls, and roof made of hollow brick tiles). The elevated height, together with a lack of sound absorbing surfaces, caused some difficulty in using the room to listen to either speech or music. In particular, before the acoustic correction works the sound reverberation times were three times higher than the optimal values, i.e. an average of 3.35 seconds at frequencies from 500-2000 Hz (frequencies at which the ear is the most sensitive) as compared to an optimal range of 1-1.2 seconds. This means that the sounds perceived in the environment were very confused and that listening in the room was difficult and uncomfortable.
The project solutions
For the acoustic correction project it was considered that the church is used to host conferences, exhibitions, and music and theatre shows; the optimal acoustic values for listening to speech were therefore taken as the primary reference. The project’s objective was to create an acoustically comfortable and versatile environment for the different types of functions expected; furthermore, the solutions were conceived by choosing products that are environmentally sustainable and, at the same time, aesthetically appealing and uniform. Natural, recycled and recyclable materials (plants, wood, rubber recycled from end-of-life tyres, and polyester coming from the recycling of PET bottles) were therefore exclusively used.
The work performed
Reflective / sound absorbing mobile panels
The sound absorbing / reflective panels make the church’s acoustics variable. Eight curved panels characterized by a completely sound-absorbing side and by a reflective side are positioned on a mobile structure on wheels. The inside contains rubber recycled from end-of-life tyres, in addition to other materials, which gives the system additional mass.
Acoustic panels suspended from the ceiling
36 curved sound absorbing panels, arranged alternately with the concave/convex side up, have been hung from the roof’s rafters. These panels leave the wooden trusses and the hollow brick tile ceiling, defining elements of the architecture of the church itself, completely visible.
Evergreen plant-based sound absorbing covering
An innovative sound absorbing covering composed of plant-based panels called Smart Acoustic Green was positioned on the back wall of the church. The “living” covering was created with Cladonia arbuscula, a species of plant native to Scandinavian countries that lives particularly well in environments with normal light, low light or even darkness.
The reverberation time measurements made following the works gave a result (as the average at frequencies of 500-2000 Hz) of 1.41 seconds in the absence of the mobile panels, 1.03 seconds with the mobile panels positioned with the reflective side visible and 0.96 seconds in the maximum acoustic absorption configuration, i.e. with the mobile panels positioned with the sound absorbing side visible. Furthermore, the distribution of the sound levels present throughout the church was very homogeneous: with a sound source located on the altar, the difference between the nearest seat and the one farthest away fell within 3 dB(A). Finally, the mobile panels can also be positioned as acoustic separation elements between the various areas of the church and, depending on the configuration chosen, cause elevated acoustic attenuations with values that exceed 10 dB(A) in the most shielded areas.
This year, in addition to the works in the church, children and parents who attend the festival can also relax and play on the furniture and on the floors made of recycled rubber created in 2014.
The furniture and play areas made of recycled rubber at Festambiente
Ecopneus has chosen to support Festambiente to showcase a real circular economy experience to the benefit of the environment we live in. The correct recycling of end-of-life tyres (ELTs) supplies the industrial system, generates jobs, eliminates pockets of lawlessness, and favours the creation of environmentally sustainable products.
In particular the festival’s spaces will showcase: injury prevention flooring, benches and seats in the lounge area dedicated to families, a multi-purpose playing field made of synthetic grass and a puzzle made of rubber titles in the area dedicated to children, where they can play as part of the activities conducted by the Legambiente educators, a bike path, a soft walkway placed in the Sustainable Living area inside the Environmentally-Friendly House, a prototype of an environmentally sustainable house, completely self-sufficient from the energy point of view, and objects for daily use such as seats, benches, planters and bicycle racks. These and many other objects created with ELT rubber can be found in the online catalogue on the Ecopneus site, from which it is possible to directly contact the companies that make them.
For technical information on the acoustic project realized at Festambiente, please visit https://www.ecopneus.it/it/spazio-sensoriale/la-nuova-acustica-della-chiesa-di-rispescia.html