The construction is designated as hostel for the pilgrims of "Camino de Santiago". The architects, Naxto Ibarrexte and Inaki Del Prim, aimed to combine in their project aspects of sustainability, healthy construction with local materials and energy efficiency.
The new construction has been released in 2020 and it is located in Zagama in the Region of Basque countries. The building develops completely on the ground floor, with its main facades open to the South and West, and with the envelope closing the orientation of the cold North-Western winds.
The structure is made of timber, with an overall surface is around 100 m2 for an occupation of twelve pilgrims.
The solution sets are aimed to minimize the energy demand by reducing the thermal transmission thanks to the highly insulated timber ventilated envelope.
In particular, the external wall is a ventilated façade insulated with 20 cm of wooden fiber and 5 cm of mineral wool, supported with a structure of cross-laminated timber and finished with a layer of OSB, for an overall U-value of 0.133 W/(m2 K).
The roof has structure made of timber too and it is ventilated and highly insulated, with 10 cm of mineral wool and 24 cm of wooden fiber for a thermal transmittance of 0.114 W/(m2 K).
The windows have a PVC frame with a U-value of 1.02 W/(m2 K) and a triple glazing 4/16/4/16/4 with warm edge and a U-value of 0.58 W/(m2 K) and a solar transmittance of 54%, balancing the thermal efficiency with the possibility of exploiting solar gains in the cold season, while for the warm season, the overhang reduces the risk of overheating.
The heating is supplied with decentralised low-consumptions splits with aero thermic generation. To further reduce the heating and cooling loads to be supplied by the system, there is a mechanical ventilation installed, with a heat recovery system with 86% of efficiency.
Moreover, a heat pump dedicated to the preparation of domestic hot water is also used for the activation of the concrete slab
As mentioned before, the design is highly focused on the reduction energy demand, with a heating demand of 11 kWh/m2 for year, but also the primary energy demand is lower then the Passive House requirements (87 kWh/m2 for the reference building), and accounts for 54 kWh/m2, considering heating, domestic hot water, household electricity and auxiliary electricity calculated according to PHPP. Also the cooling demand is significantly low, with a yearly energy need of 10 kWh/m2.
More information on the building are available in English on the PH Database.