The site was once home to a large piston factory that lay at the heart of this bustling north German port city. Going back almost one hundred years, the factory produced pistons for aircraft, ships and cars. But fierce competition from other piston manufacturers worldwide made it difficult for the factory to continue, and, after a long struggle, it was finally forced to discontinue operations. Many workers lost their jobs, and there was an outcry throughout the city.

By 2009, what started off as a sad tale was a painful reality for all involved. But the story of the flourishing redevelopment of the former piston factory is the closest thing you will hear to a fairy tale – and one that literally came true. But let’s tell the story in the right order and not get ahead of ourselves.

A site encompassing 35,000 square metres – that’s roughly five times the size of the footfall pitch in Hamburg’s Volksparkstadion – couldn’t just go unused or be left to become derelict. The initial idea was to find an interim use for the site while a new development plan was drawn up for the district. Everyone knew beforehand that this would be years in the making. The plan was to breathe life into the site without hampering necessary construction measures. The vibrant diversity this created would come to characterize the site’s further development and use.

Resourceful tradespeople were the first to discover the potential of this industrial wasteland with its stylish brick buildings, which once formed the backdrop of an Evelyn Hamann crime scene. In short order, part of the area along Hamburg’s Friedensallee was transformed into a thriving business location, which in the years that followed served repeatedly as a cool setting for numerous cultural events. The reasonable rents attracted not just small workshops and trade businesses but also members of the arts and culture community to come and settle there. The concept took off, and a “Kolbenhöfe e.V.” association was established to represent the interests of the new tenants, which later went on to become a cooperative.

An extensive clean-up operation

Use as an industrial premises for nearly 80 years inevitably left its mark, due not least to the presense of a foundry on the site. Once the site had been inspected by independent experts, an extensive clean-up was required, which initially involved tearing down parts of the halls. During the clean-up operation, which was approved by the Hamburg government agency for environment and energy, the contaminated earth was removed and replaced with fresh soil. This literally prepared the ground for a healthy new living and working environment.

Intensive public participation

But that wasn’t enough. he planning process for the site and surrounding district first had to ensure that the outcome would meet the needs not only of the city, but also its residents, and be commercially viable at the same time. A regulation in Hamburg prescribes that 30 percent of new residential developments must consist of social housing.

“From the outset, we insisted on an intensive public-participation process for development and design of the new district. After all, to succeed in the long term, a development project has to proceed in close cooperation with the city district,” says Holger Gradzielski, managing director of Rheinmetall Immobilien GmbH (RIG), which owns the former factory site in the Altona borough. “But”, Gradzielski is quick to add, “the solution has to be commercially viable as well!”

In 2013 the “Dialogwerkstatt Friedensallee” was founded. This “dialogue workshop” not only allowed residents to look at the potential plans but also let them contribute their own ideas to the planning process. Regional representatives of the Altona borough were also involved in the launch of an urban design competition, with ten architecture firms taking part. The areas were to be divided equally between living spaces and business spaces.

The designs were evaluated by a jury, with the public included in the whole process at every turn in a transparent workshop, not to mention special information points detailing the development planning process. The competition yielded a successful blend of existing structures with the new residential buildings, which are connected by courtyard areas. Anyone who is interested can look up the development and find out how building is progressing by going to www.kolbenhoefe.de, which is still active, in addition to a live webcam.

The fairy tale continues

Finally, in 2018, the official planning phase of the Ottensen development plan was practically complete. The plan included a property owned by Henkel through its subsidiary Schwarzkopf, which is directly adjacent to the Kolbenhöfe site. In the same year, RIG, which had meanwhile embarked on a joint venture with Otto Wulff Projektentwicklung GmbH, was able to acquire, develop, and build on this additional 46,000 square metres of land. Another player involved in the project is the Altona savings and building association (altoba), which had previously acquired two building sites totalling 13,000 square metres on the Kolbenhöfe site and is responsible for planning and building social housing there.

he expansion marked the birth of Kolbenhöfe II. This was a unique opportunity for RIG, as Gradzielski explains: “Both plots are part of the Ottensen development plan, and they went through the planning process together. This meant we were aware of the specifics of the new space, which simplified development of the entire area for us to a significant extent.”

As the area of the Kolbenhöfe district increased, so too did the number of flats, which grew to around 680, with roughly 200 of these earmarked for social housing. And because a proper neighbourhood needs a space where things like a weekly market can be held, the Kolbenhöfe district also has a prominent local square.

Vibrant diversity proves a marketing success

Good ideas spread quickly, and Kolbenhöfe is no different. Besides the already renovated Hall 7, RIG has succeeded in reselling some of the residential buildings, which are still under construction. The buyer is purchasing 163 completed rental flats, 26 of which are social housing, and 6 commercial units.

Another prominent buyer is the Hamburger Konservatorium music conservatory, which is establishing its new premises at Kolbenhöfe. This longstanding centre of musical learning will move into a converted former warehouse building, which it will use as a music school and academy, complete with rehearsal and seminar rooms. A new concert hall is also being built, which will be structurally connected to the warehouse building. A musical day-care centre will also liven things up in this blend of historical and new buildings, the hallmark of a vibrant and diverse district development.

Within the walls of the Konservatorium’s music school and academy and at its many other sociocultural initiatives, 11,000 pupils, 300 students, and 240 lecturers will play music in spaces that once beat to the rhythm of casting machinery.

Solid ground

What about the craftspeople and tradespeople? They have invested in Kolbenhöfe as well, jointly purchasing their hall through their own cooperative, the Genossenschaft Kolbenwerk eG, with the help and support of RIG, which has tailored the building to meet the individual needs of the new owners, bringing it up to the latest technical standards. Nearly thirty small businesses operate there now, including a vintage car workshop, a motorcycle self-help store, a metalsmith, a joinery, a surfboard builder’s shop, as well as media and creative businesses. Roughly 100 people work in this building. The new owners are unanimously pleased to be able to keep working on solid ground in the extensively renovated halls and rooms. Given their shared history, this is an especially happy development, and we hope that they all live happily ever after.

Central location
The Kolbenhöfe site, which covers 8.5 hectares in Hamburg’s Ottensen borough, is one of many individual projects forming the central core of the future district at Friedensallee, which will house a total of 1,200 new apartments, of which around 400 will be social housing. The area also encompasses space for small businesses, a day-care centre, and offices for upwards of 1,500 workers – not to mention the thirty or so workshops in the former factory hall, which has been renovated from the ground up.