ecotonos by Slalom & UNA/UNLESS debuts at Open Air Design 2025
Slalom and UNA/UNLESS unveil Ecotonos, a site-specific acoustic installation premiering at Open Air Design 2025, held September 18–21 at BAM – Biblioteca degli Alberi, Milan. Designed by architect Giulia Foscari, founder of UNA/UNLESS, the project merges Slalom’s acoustic expertise with a conceptual framework rooted in ecology, cinema, and multispecies coexistence. Staged within the event’s theme ‘Frames of Nature,’ the installation explores silence and listening as tools for reconnection between city and biodiversity, while extending research from UNA/UNLESS’s Voice of Commons project at the Venice Architecture Biennale.
This immersive vision did not stand alone. During the same days, Ecotonos became a catalyst for a wider cultural program. The installation joined a broader series of public conversations exploring design, cinema, and urban ecologies. Moderated by Francesca Molteni, the talks united designers, curators, actors, and musicians. The opening event featured Giulia Foscari alongside cultural figures including Rosita Celentano, Giampiero Judica, and Patrizia Sardo Marras, with contributions from Alida Catella of COIMA Image and Caterina Mosca of MoscaPartners. Additional sessions, including one led by architect Michele De Lucchi, expanded on the role of nature within contemporary urban imaginaries. The program is accompanied by three open-air screenings focused on architecture and design.
Slalom takes part in BAM Open Air Design with Ecotonos, a site-specific installation that brings together the brands’s expertise in acoustics and the design vision of UNA/UNLESS | all images courtesy of Slalom
an acoustic multispecies architecture
Established in 2012 by Elettra de Pellegrin, Slalom specializes in high-performance acoustic panels for contract, cultural, and public environments. Their approach centers on circularity, using post-consumer plastics transformed into PETfelt, along with wool, wood, and natural fibers. Every product is designed for durability, recyclability, and reusability, in line with the 2030 Agenda and ESG principles. De Pellegrin’s guiding concept of ‘Acoustethics’ merges functional sound performance with tactile and visual refinement, a philosophy clearly embodied in Ecotonos.
This shared attention to material intelligence and environmental responsibility forms the bridge to UNA’s practice.
Founded by Giulia Foscari, UNA operates globally across cultural, residential, and product design, with a portfolio that includes work for the Anish Kapoor Art Foundation and LAS Art Foundation. Running parallel to the practice, the UNLESS Foundation ETS advances interdisciplinary research on the Global Commons, notably through Antarctica-focused initiatives such as Antarctic Resolution. UNA/UNLESS’s work is characterized by a belief in preservation as radical sustainability, a principle that anchors both Voice of Commons and Ecotonos.
the event investigates how nature and culture can intersect, offering the public a unique and inclusive outdoor experience
ecotonos absorbs sounds with diamond-like surface
Ecotonos appears as a fractured prism in the center of the park, a sculptural threshold that divides the sensory regimes of the city and the natural environment. The installation borrows its name from ‘ecotones,’ the transition zones between ecosystems where diversity concentrates. On one side, its diamond-like, reflective surface dematerializes the skyline into ghostly mirages; on the other, it opens into a soft, honeycomb-like interior carved with cavities that recall a beehive. This geometry absorbs and modulates sound, dampening mechanical noise and amplifying subtle natural frequencies, from bees’ vibrations to the rustling of leaves.
The installation functions as an interspecies refuge, integrating plug-in components to host seeds, microhabitats, and water stations for insects and birds. These ‘cells’ are designed not as decorative motifs but as active spatial tools for supporting biodiversity. Ecotonos frames nature not as scenery but as protagonist, creating a micro-sanctuary that encourages visitors to slow down, listen, and engage with the more-than-human world. In this gesture, the work becomes a political threshold between extraction and care, proposing silence as an act of resistance.
in the heart of the park, a fractured prism emerges as a threshold between two worlds: the city and nature
Ecotonos carries forward material research developed for Voice of Commons, presented by UNA/UNLESS as a Special Project of the 2025 Venice Architecture Biennale. At the Biennale, Carlo Scarpa’s restored ticket office becomes a Planetary Embassy dedicated to the Global Commons, where Slalom and UNA/UNLESS experimented with acoustic ‘Spikes’ developed using space-inspired techniques. At BAM, these surfaces reappear in an evolved, sustainable form, inaugurating a new line of sound-absorbing products designed with recycled, regenerated, and natural materials—a move away from conventional petroleum-based polyurethane.
Open Air Design 2025 adopts cinema as a conceptual backbone, a theme that resonates throughout Ecotonos. The installation echoes Werner Herzog’s Encounters at the End of the World, where the silence of Antarctica reveals otherwise imperceptible natural phenomena. Similarly, Ecotonos aims to suspend urban noise and cultivate a state of attentive stillness, where interspecies interactions gain clarity. This cinematic sensibility transforms the installation into a narrative device, a frame through which the public perceives new relations between the city, nature, and sound.
in the park-facing side, the installation opens up. It welcomes. It softens mechanical noise to allow the breathing of bees
its interior, sculpted with regular cavities, recalls a honeycom
the ‘cells’ invite participation, with plug-in elements designed to host life
this dual orientation is an architectural expression of the tensions that define our age: extraction versus care, blind growth versus radical listening
Elettra de Pellegrin, founder of Slalom (left) with Giulia Foscari, founder of UNA/UNLESS (right)
project info:
name: Ecotonos
company: Slalom | @slalom.acoustic
event: BAM Open Air Design
design: Giulia Foscari
design vision: UNA/UNLESS | @una_unless
location: Biblioteca degli Alberi, Milan, Italy
dates: September 18-21, 2025
photography: DSL Studio | @dsl__studio
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