Tor Alva, a modular 3D‑printed concrete tower designed for disassembly and reuse, standing on the Julier Pass in the Swiss Alps.
Mulegns, Julier Pass, Swiss Alps, August 13, 2025
Tor Alva, also called the White Tower, is a 30‑metre, four‑storey modular tower built with robotic 3D printing of hollow concrete columns. Designed and fabricated using coordinated robot arms, a fast‑hardening soft concrete mix and embedded reinforcement, the structure uses dry connections and removable fastenings so it can be disassembled and re‑erected elsewhere. The tower houses a vaulted top‑floor concert space and twisting interior rooms, and was developed with industry partners to explore circular construction, lower lifetime waste and strategies to extend service life despite material trade‑offs in embodied carbon.
A 30‑metre tall, four‑storey tower named Tor Alva opened in Mulegns on the Julier Pass in the Swiss Alps on 20 May 2025. The structure, described by its project team as the world’s tallest 3D‑printed concrete tower, was completed in May 2025 and is scheduled to remain on site for roughly five years before it can be dismantled and reassembled elsewhere. From 23 May 2025 the tower is open daily for guided tours, and staged performances are planned to begin in July 2025.
Tor Alva, also called the White Tower, was commissioned by a cultural foundation to serve as a temporary venue for art installations, music, and theatre. The project was designed by two architects and developed by ETH Zurich through an interdisciplinary collaboration involving digital fabrication, structural engineering, and materials science groups. The initiative was supported by an academic foundation, the local Surses community, private donors, industry partners and two university spin‑offs. Industry partners included well‑known material and chemical firms, while the work was framed within a national research centre focused on digital fabrication.
The tower is a modular, four‑storey building that rises to 30 metres including its base. Internally it is formed by a set of branching, twisting hollow columns — around 32 columns wrap and define abstract interior rooms, with vertical stair access and a vaulted concert space at the top floor offering panoramic views across the Julier valley. The exterior is largely windowless and shows a criss‑cross texture that reflects the layered 3D printing process. The tower is fitted with programmable lighting for nighttime illumination.
Tor Alva uses a robotic, layered extrusion process that required no traditional formwork. The project team produced hollow, joint‑based columns by extruding a soft, fine‑grain concrete in thin layers. A bespoke additive was developed to make the mix harden quickly enough for subsequent layers while remaining malleable during deposition. The fabrication workflow integrated two coordinated robots: one robotic arm extruded the concrete into freeform shapes and a second robot placed reinforcement between layers during printing.
The reinforcement approach was hybrid. Horizontal stainless steel rings were embedded during printing, vertical rods were inserted after printing and their cavities filled with self‑compacting mortar, and prestressed rods were used in upper sections to improve crack resistance. Stainless steel was chosen for corrosion resistance and durability. The printed components were designed to connect with dry connections, removable screws and prestressed joints, avoiding adhesives so parts can be dismantled and reused elsewhere.
Printing of the columns began on 1 February 2024. The first eight lower‑floor columns were printed by a robot at the university’s fabrication facilities in Zurich and then transported and assembled on site in May 2024. Final completion and public unveiling occurred in May 2025. The project team reports the printed columns were self‑supporting as layers hardened fast enough to accept further deposition.
The team developed a printing mix that is more specialized than conventional concrete and acknowledged that this mix can have a higher embodied carbon footprint than some standard alternatives. To address environmental impact, the project used stainless steel for long‑life reinforcement, pursued design measures to accelerate concrete carbonation so the material can reabsorb atmospheric CO₂ over time, and prioritized reuse through modular, detachable connections. The designers also argue that hollow, optimized shapes and the printing process can save mass and cement relative to traditional methods, which can reduce production emissions in some comparisons.
The work united several university research groups focused on digital building technologies, structural analysis and building materials, and it drew on the university’s robotic fabrication facilities. Two university spin‑offs participated, alongside industry partners providing material, chemical and finishing systems. The project sits alongside other digital fabrication research at the institution, including experiments with low‑carbon, cement‑free deposition methods and reusable lightweight formwork systems.
Tor Alva is intended as a cultural installation for intimate performances and exhibitions. The modular strategy allows the tower to be dismantled using removable screws and moved or re‑erected elsewhere after its initial five‑year stay in Mulegns. The design aims to demonstrate circular construction principles: components are produced to be reused, and the fabrication workflow links computational design, robotic fabrication, structural engineering and materials research.
The tower forms part of a broader push in automated and robotic construction research at the university that explores material efficiency, form‑finding, and new reinforcement and deposition techniques. Other projects under the same research umbrella include a reusable folding formwork system that cuts concrete and steel use and an experimental high‑speed deposition method for low‑carbon materials intended for unstructured sites. Together, these efforts highlight the trade‑offs and opportunities when blending robotics, tailored materials and modular design.
Tor Alva is a 30‑metre, four‑storey modular tower in Mulegns built primarily from 3D‑printed hollow concrete columns and designed to be dismantled and reused.
The tower was unveiled on 20 May 2025 in Mulegns on the Julier Pass, with guided tours starting 23 May 2025 and staged performances planned from July 2025.
The structure was produced using coordinated robotic fabrication: one robot extruded a soft, fast‑hardening concrete mix layer‑by‑layer while a second robot placed reinforcement between layers. Hybrid reinforcement and prestressed rods were incorporated for strength.
The tower is planned to remain in Mulegns for about five years and was designed with removable screws, dry connections and prestressed joints so components can be dismantled, transported and re‑erected elsewhere.
The printing mix is specialized and can have a higher embodied carbon footprint than some conventional mixes, but the project includes measures to reduce impact: optimized hollow geometry to save material, stainless steel for durability, a carbonation strategy to reabsorb CO₂ over time, and modular reuse to extend life span.
The project was developed by an interdisciplinary team at a Swiss technical university with academic groups for digital building technologies, structural analysis and building materials, supported by an academic foundation, local community, private donors, industry partners and university spin‑offs.
| Feature | Detail |
|---|---|
| Project name | Tor Alva (the White Tower) |
| Location | Mulegns, Julier Pass, Swiss Alps |
| Height | 30 metres (including base) |
| Program | Four storeys; vaulted top concert room; vertical stairs |
| Construction method | Robotic 3D printing of hollow columns with coordinated reinforcement placement |
| Reinforcement | Embedded horizontal stainless steel rings, vertical rods filled with mortar, and prestressed rods in upper sections |
| Materials | Custom fine‑grain soft concrete with quick‑setting additive; stainless steel reinforcement |
| Modularity | Components joined with removable screws and dry connections for disassembly and reuse |
| Timeline | Column printing began 1 Feb 2024; on‑site assembly May 2024; completed and unveiled May 2025 |
| Public access | Guided tours daily from 23 May 2025; performances from July 2025 |
| Planned lifespan on site | About five years before potential relocation |
South Lake Tahoe and Salt Lake City, August 13, 2025 News Summary Major moves are unfolding…
Morris, Illinois, August 13, 2025 News Summary District leaders unveiled a financing roadmap to fund a…
1506 Van Ness Ave, August 13, 2025 News Summary City leaders propose a 36-month market-rate bridge…
First Hill, Seattle, August 13, 2025 News Summary A private K–5 school has applied for a…
Hamburg, August 13, 2025 News Summary Plancraft, a Hamburg-based construction software startup, closed a €38 million…
Alabama, August 13, 2025 News Summary Birmingham-based construction and program management firm HPM has partnered with…