The “Werkblock” residential complex in Bremerhaven is an architecturally and historically significant building complex that was constructed in the 1930s. The residential complex, which comprises over 100 flats, has been a listed building since 2009. The challenge: how can the building be renovated to improve its energy efficiency while protecting its historical substance?
The solution: thermal insulation of the cavity walls with Clay Foam
The mineral insulation system Cavipor® was used for the retrofitting of the façade. This innovative in-situ foam system was specially developed for the renovation of buildings with double-wall masonry – a construction method that is particularly widespread in northern Germany.
Renovation process
- Analysis & preparation: Inspection of the cavity layer and identification of drilling points.
- Insertion of the insulation material: Cavipor® foam was inserted into the cavity layer through small drill holes. Thanks to its fluidity, it fills even hard-to-reach areas completely and seals itself automatically.
- Completion & inspection: After hardening, the drill holes were sealed with joint mortar. The historic façade remained completely intact and undamaged – a major advantage for listed buildings.
The result: the perfect combination of heritage preservation and energy-efficient modernisation
The renovation of the Werkblock residential complex shows how modern insulation technology can be seamlessly integrated into historic architecture. Cavipor® significantly improves energy efficiency without making any visible changes to the façade or structure. It is a solution that combines sustainability, cost-effectiveness and architectural sensitivity.
Technical results:
• U-value of the wall before: 1.7 W/m²K
• U-value of the wall after: 0.5 W/m²K
• Financial amortisation: 5–7 years
• CO₂ amortisation: 4–8 months
