Omega House Revitalisation

Beyond the building envelope, the entire technical infrastructure was overhauled. A mechanical ventilation system now ensures proper air exchange, replacing the former purely manual window ventilation, while comprehensive cooling ceilings manage the temperature control throughout the offices. To align the property with current ESG criteria, the ground floor features a campus concept that includes a daycare center, a conference facility, a fitness studio, and gastronomy services. Furthermore, the mobility infrastructure incorporates 820 bicycle parking spaces as well as EV charging stations in the in-house underground garage.

A central element of this circular refurbishment is the facade. Approximately 5,000 window sashes were replaced, while the intact outer frames were kept in place. The old sashes were systematically dismantled on-site and strictly sorted by material type before being returned to their respective industries without any downcycling. The scrap aluminum was repurposed into new profiles containing at least 75 percent end-of-life material, which lowers the carbon footprint to 1.9 kilograms of CO₂ per kilogram. Similarly, the old glass serves as a 64 percent raw material base for new, CO₂-reduced flat glass. The EPDM rubber seals were devulcanized and manufactured into new seals, cutting their CO₂ emissions by 47 percent.

To precisely compensate for existing structural tolerances when installing the new window sashes onto the old framework, a project-specific adapter frame was utilized. Thanks to this system, up to 150 windows could be renewed per week on the construction site, achieving a U-value of less than 0.99 W/m²K.

Text: ZAB | Sources: Oaktree Capital Management, BauSmart Consult, Lefair Development, Büro WGA ZT GmbH, Heidenbauer, Wicona, Saint-Gobain Glass, Semperit