Consistently Modular: Duplex by Valparaíso
The double house built for two brothers on the outskirts of the town of Cachagua, located on the Pacific coast of Chile, asserts itself entirely in black. For a long time, architect Alejandro Soffia had planned to use wood panelling for the façades and roof. Ultimately, he decided in favour of a more durable cladding of dark fibre cement. Inside, the walls and ceilings are covered with light-coloured pinewood. This may make it difficult to immediately detect the structural assembly of the house; however, the façades and their room-high windows still hint at the modular construction.
The house serves its owners as a second home for holidays and weekends. Each of the two couples has four children. Moreover, each half of the duplex was to have a room for a domestic worker. One of the two living units has an additional guest room as well. The floor plan is a variation on the typology of the traditional shotgun houses of the southern United States. These are accessed from the narrow end and comprise a single sequence of rooms extending to the back of the property. In contrast, Soffia’s design has placed the entrances to the house in a single-storey annex on the south side.
For this building, Soffia relied to a large extent on structural insulated panels, or SIPs for short. These self-supporting sandwich panels consist of an insulated core of rigid foam between two layers of OSB panelling. Most SIPs are now made with standardized OSB layers measuring 122 x 488 cm. In this case, the longer side determined the width of the house, while the shorter side forms the basic modules for the façades. In order to give them additional flexural rigidity, the sandwich panels have been reinforced by wood and, in some places, steel profiles along their edges.