onar Real Estate (Sonar) has successfully leased the first rental space for the PRISMA office building in Frankfurt's Lyon district, which is currently still under renovation. The long-term lease of around 6,500 square metres of office space by adesso SE, a leading consulting and IT services company, sets a first anchor point for the future use of the building as an open, flexible multi-tenant property. At the same time, the letting initiates the transition from the structural revitalisation phase to the active use of one of the most ambitious ESG projects on the German office market.
"With PRISMA, we have created a modern office building together with our partners that combines quality of stay, sustainability impact and modern urban development. At the same time, we have shown that the older a building is, the more sustainable it can become," explains Holger Hosang, Managing Partner of Sonar. The start of letting shows that the market is in demand for precisely such offers, especially in the current situation of upheaval in the office market."
The offices that have now been rented are expected to be occupied after the upcoming expansion of the space in spring 2026. "We are very pleased to be able to remain loyal to the Lyoner Quartier and to move into a building that impresses with contemporary, sustainable space and a highly flexible concept. For our team, this is the ideal combination of continuity and quality. At the same time, the surrounding area offers a wide range of shopping and dining options that invite you to enjoy and discover both during breaks and after work," says Thomas Bayer, Frankfurt am Main Site Manager at adesso SE.
Revitalisation with substance: 50,000 m² rethought
Sonar acquired PRISMA in 2022 together with a fund advised by Patron Capital Advisers. After the only tenant, Deka Bank, moved out, the approximately 50,000 m² gross floor area, of which around 44,000 m² is office space, was subjected to a portfolio transformation in Frankfurt. In cooperation with the renowned Frankfurt architectural firm "holger meyer architektur", the office building from the 1990s was raised to a new level in terms of technology, energy efficiency and design. This makes PRISMA one of the most ambitious ESG renovations in the German office real estate market. The primary energy requirement was reduced by 55% in the course of the modernization. The building meets the KfW 55 standard. The projected CO₂ emissions are less than three kilograms per square meter and year. Over the entire life cycle, this results in savings of around 42% compared to a conventional new building. For this reason, the sustainability certificates "DGNB Platinum" and "BREEAM Excellent" are being sought.
Integrated circular construction
Another key feature is the consistently implemented re-use approach: In cooperation with specialised partners, all fixtures, materials and furniture in the existing building were tested for reusability. Whenever possible, integration takes place in the building; unused elements are returned to the material cycle. The aim is to make a measurable ecological contribution beyond pure energy consumption.
The office space itself offers a wide range of possible uses – from classic individual offices to open team zones and hybrid room concepts. The flexibility of the floor plans allows individual working environments to be realised that meet the requirements of a wide range of user groups.
Social openness and urban relevance
In addition to the technical and ecological aspects, the project also pursues a clear community-building approach: The focus is on the 45-metre-high atrium with an area of around 3,000 m², which will be open to the public and multifunctional for gastronomy, conferences, coworking, exhibitions and events in the future. This will actively integrate the building into the social space of the district. A special architectural element here is a floating art installation, which gives the place additional visual identity. In addition, the former canteen was converted into a publicly accessible restaurant with a barista offer and areas for a fitness studio were planned.
Driving force for the "Lyon Quarter"
With its striking presence and integrative concept, PRISMA plays a decisive role in the transformation of the Lyon district in Frankfurt-Niederrad. "The structural change from a pure office location to a lively, urban district is significantly shaped by projects like this. With the PRISMA, we are making a contribution to transforming Niederrad into a lively, urban location that combines living and working environments in the best possible way. At the same time, the object impressively shows that economy and ecology are not opposites, but equal components in a sustainably conceived urban society," emphasizes Holger Hosang, Managing Partner of Sonar.
The conversion work is scheduled to be completed by the end of 2025. Further talks are already being held with potential tenants.
In the current letting, Savills has taken over the advice of the owner, JLL that of the tenant. Gowling WLG worked for Sonar as a lawyer.
