Up to three apartments could be craned into position in a day (Virtuel)
A renovation project in the town of Poissy, on the north-western outskirts of Paris, has succeeded in adding 33 new units to an existing building by fitting prefabricated modules to their roofs.
The project, for client Vilogia, was designed by Parisian firm Virtuel Architecture and used Kerto modules from Finnish wood fabricator MetsÃ¤ Wood. The modules were machined by French company Construction Millet Bois at its factory in Mauléon near the Pyrenees.
Altogether, 33 apartments were constructed on top of existing residential blocks in the Beauregard neighbourhood. The process took about six months.
Each apartment is made from laminated veneer lumber, which is made from thin layers of wood glued together. This kind of engineered wood has the advantage of being dimensionally stable as temperature and humidity varies.
The completed project (Virtuel)
The modules have two and three bedrooms. The construction project also included the installation of three elevators and extension to the staircases.
Laurent Pillaud, an architect at Virtuel, commented: "Each house is made up of three or four modules and one roof; the production of the modules took one month. Then the modules were delivered and each was installed directly on the rooftop in one day."
He added that the joints between the modules were carefully planned so each could be quickly connected to other modules and to roof structures.
MetsÃ¤ Wood’s graphic, showing the construction process