Danish Firm to Build Tall, Timber Tower in Switzerland

Northeast of Zürich, Switzerland lies Winterthur, a former industrial town that used to make locomotives out of steel. Now, it is going to be home to a neighborhood of housing, retail, hotel, and student housing built of wood.

Included in the complex being designed by Danish firm Schmidt Hammer Lassen Architects (SHL) is a 32-story, 328-foot (100-meter) tower that is being described as the world's tallest wooden tower. It is named Rocket&Tigerli after two famous locomotives—one British and one Swiss. The firm got the gig by winning a limited architectural competition, up against the likes of the Bjarke Ingels Group and 3XN.

I have always resisted writing about "the world's tallest timber tower" because it is so ephemeral— someone is always announcing a taller one the next day. And being taller isn't always better in urban design. I tend to promote what I have called the Goldilocks density where you are not necessarily dependent on elevators. In this silly race to be called the tallest wood tower, I believe you can have too much of a wood thing.

But one should never be doctrinaire. There's a lot to admire in this proposal that goes beyond height, even though that's why it is getting all the press coverage. The architects note:

"The project marks a milestone in the construction of timber buildings – not solely because of its 100 metres, which set the record for residential buildings with a load-bearing timber construction, but also because it introduces an innovative construction system that examines wood as a natural replacement for concrete. The Swiss company Implenia and the Swiss Federal Institute of Technology of Zürich, ETH, have worked together in developing the new system, which allows the construction of taller timber buildings. In the new system, the concrete core has been replaced with wood, resulting in the fact that the individual beam comes in at a lower weight. This makes it possible to build taller constructions while, at the same time, ensures that the entire building process achieves a lower amount of embedded carbon."

There is also no question that Schmidt Hammer Lassen knows wood. “At SHL it is a tradition to design in wood, which is expressed through ongoing projects in Oslo, Dordrecht, Toronto, and Vancouver," said Kristian Ahlmark, Schmidt Hammer Lassen partner and design director. "We have always been proactive in our use of the material, not just because of its aesthetic qualities, but also because of the technical construction possibilities it paves the way for. The new production method, presented in this project, brings our love for the material into a modern building.”

The wood inside is all exposed, which is not something that can be done at this height in most jurisdictions but is, as always, lovely to look at in the renderings. The firm stated: "SHL’s proposal celebrates the structure of the construction itself through architectonic effects, where the wooden beams are highlighted as a distinctive element that gives the residents a sense of living inside the construction."

According to the developer Lokstadt, "What is special about the Rocket is not only its height and its construction with wood, but also its planning: the apartments are developed in dialogue with the future tenants and are designed for maximum flexibility in the room layout and use, so that they can be changed over time can be adapted to changing housing needs." There are 255 units ranging from 1.5 to 5.5 rooms, each with a balcony.

The plans are fascinating from a North American perspective. The plan above is from the lower Tigerli building. Note how even though the shape of the floor plate is similar to that of North American buildings and there are two stairs, there is no corridor connecting them. As such, you get short corridors and greater efficiency, somewhat offset by the fact that there is probably an extra elevator.

Another fascinating detail is the exterior cladding; Schmidt Hammer Lassen has been around wood buildings long enough to know you use it inside, not outside. They have clad the Rocket Tower "in dark red and yellow terracotta bricks combined with details in dusty green; a colour palette that reflects the red roofs and yellow bricks of the historical buildings in the area." Terra Cotta is made of clay and is fired at high temperatures, so it does come with a load of embodied carbon, but according to one manufacturer, Boston Valley, a lot less than other usual cladding materials.

Since all the attention is being paid to the tower, we should point out there is more to the project, including an interesting site plan tying the different buildings together. The jury notes Schmidt Hammer Lassen did not follow the original master plan: "By dissolving the original block structure and integrating the detached buildings a larger façade area is achieved and thus more daylight, as well as a stronger connection to the surrounding environment."

So all of this begs the question: Have we finally moved on from talking about the tallest wood tower and can we get back to talking about architecture and the quality of the building?

This project has nothing like the silly wood hat on the timber tower in the middle of nowhere which made Brumunddal, Norway's Mjøstårnet temporarily the tallest. That's the one that made me write: "It may be treesonous of me to say this, but we should stop this silly competition to be tallest." Or Berlin's WoHo Tower that was clad in wood and plants—neither wood nor plants do well so high in the sky. It caused one of the world's best architects of wood buildings, Andrew Waugh of Waugh Thistleton, to tell us, "Isn’t this competitive endless growth and increased use of stuff what got us into this position in the first place?"

Rocket&Tigerli feels different. The architects sound different, with Ahlmark saying: “We approach this project with a great sense of humbleness. It is a big project that will have a significant influence on the community, socially as well as aesthetically. Because of the strong expertise Switzerland has, when it comes to building in wood, we are particularly proud to be working on this ground-breaking project.”

It may have the world's tallest timber tower for a few moments, but there is more to this project than just a lot of tall wood.