BA RSoft pre-slabs and RSoft low-carbon Rector pre-walls for the first building reaching the 2028 thresholds of RE2020 in Alsace

In a gap in the city centre of Mulhouse, the real estate developer Vitruve is building the Simone Veil residence, made up of 13 low-rent housing units. He wanted to make this project, which responds to the problem of urban densification, an exemplary model in terms of carbon emissions and thermal performance.

For this first building in Alsace reaching the 2028 thresholds of RE2020, Rector's RSOFT BA pre-slabs and RSOFT pre-walls in prefabricated concrete were selected as the most relevant solutions to meet all these expectations.

As part of a problem of urban densification (footprint of 500 m2), the construction of the Simone Veil residence, made up of 13 dwellings on 4 floors, required an optimization of the construction method, the maximum reduction of the duration of the construction site and prevented any storage of materials on site.

In addition, the developer Vitruve wanted to create, for its client In'li, a subsidiary of the Action Logement group, a virtuous environmental achievement going beyond the regulations in force and reaching the 2028 carbon emission thresholds of RE2020.

Rector low-carbon pre-slabs and pre-walls: a new way of building

To achieve its objective, the developer has embarked on a new way of designing housing right from the design phase. It has therefore chosen the Caméléo construction system from Rector, comprising 1178 m2 of RSOFT BA pre-slabs and 845 m2 of RSOFT pre-walls in prefabricated low-carbon concrete.

Thanks to this new construction system composed of a frame of posts and a low-carbon reinforced concrete slab associated with RSOFT pre-walls, the teams have prioritized a study time upstream in order to optimize and reduce execution times during construction. Indeed, "everything that is delivered is immediately installed. In just three and a half months of structural work, four floors have already risen from the ground" explains the Dallamano company. In addition to allowing rapid assembly, the use of Rector's low-carbon prefabricated solutions avoids the storage of materials in a restricted space, right in the city center.

For Armelle Freys, Head of Sales for the North East Region at Rector: "For this particularly innovative project, our modular, reversible and frugal construction system facilitates its decarbonization. All our low-carbon concrete pre-slabs are produced locally in Alsace, in Weyersheim. These are custom-made parts, manufactured in the factory, with a significantly reduced carbon footprint and which include recycled materials."

Started in July 2024, the residence, which will have a wooden facade, should be delivered at the end of 2025. This first achievement in Alsace, reaching the 2028 thresholds of RE2020, also avoids the extension of soil artificialization and meets the requirements of the ZAN law " concludes Romain Hartmann, one of the two partners of the real estate development company Vitruve.