To ensure adaptability to a wide variety of contexts, the project is testing its innovative approach in four real case studies located in different climate zones.
The demonstration case of Soest, in the Netherlands, has recently completed its deep renovation process. It is a residential building for elderly people owned by the social housing agency WOONZORG NEDERLAND.
The demo case, named Mariënheuvel, counts 79 apartments and was built in 1980 with poor thermal insulation standards. Originally, the building was characterised by a poorly insulated cavity brick wall with a concrete structure and thermal bridges, first generation of double-glazing windows and a central condensing boiler, which had been recently renovated.
4RinEU deep renovation aimed at reducing yearly net primary energy demand by 60%, corresponding to an energy class A for the Dutch labelling scheme.
In addition, the project’s ambition was to reduce the life cycle cost of the investment of 15% and halve the duration of the construction time for the renovation in comparison to a standard intervention.
To reach the objectives, TRECODOME developed the proposed renovation package which was based on high performance prefabricated elements with wooden structure to be applied to the existing façade, with the integration of windows and shading systems and inlet-outlet ventilation through the window frame.
Moreover, the renovation project included the insulation of the roof and the installation of a new decentralised HVAC system in each household, which in the 15 apartments renovated with 4RinEU approach was integrated with a heat recovery radiator positioned under the window in the living room.
The company appointed for the façade supply was Prefabfabriek Culemborg, which worked on the preparation of the façade for the installation in correspondence with 15 apartments, the core of the building interested by the deep renovation intervention.
The rest of the construction was renovated with traditional technologies.
One of the successful features of the prefabricated façade, was the perfect match with the traditional one: in fact, due to aesthetic needs, the finishing was realized with a brick layer, usually not applied in prefabricated modules.
In this case, the company applied gypsum and wooden elements that replicate the aspect of the surrounding buildings to harmonize the prefabricated façade with the rest of the renovation.
Before installing the prefabricated modules, the existing windows were removed and replaced with the ones integrated in the new prefabricated façade.
To ease the installation, the prefabricated modules are equipped with an adaptation layer to ensure a proper matching with the existing façade that, in some cases, can present irregularities.
The thermal transmittance of the walls after renovation is 0.12 W/(m2K), significantly lower than the minimum requirement adopted for a standard intervention, accounting for 0.68 W/(m2K).
The high performances of the walls have been ensured by 4 cm of mineral wool and 23 cm of cellulose insulation in the façade stratigraphy. The integrated windows presented a thermal transmittance of 1 W/(m2K), with triple glazing and integrated shading systems.
TRECODOME calculated the estimated energy demand with PHPP. Thanks to the renovation, the net heat demand accounts for 20 kWh/m2, significantly lower than the existing building (108 kWh/m2) and the targets reachable with a standard renovation, estimated as 67 kWh/m2.
The next step towards the finalization of 4RinEU project will be to monitor the actual performances after renovation, in order to demonstrate the effectiveness of the renovation with real measurements.
For information on the renovation of Mariënheuvel, visit the project website.