The building, designed by Ruben Muedra and developed by IDAI NATURE as their new headquarters, won the BUILD Sustainable Building "Excellence Award for Sustainable Architectural Design".
It has been completed in 2018 and it is located in the town of La Pobla de Vallbona in Valencia,where the main challenge was to meet the limiting cooling demands required for Passivhaus certification, in a warm climate and in a high internal gain building.
The treated floor area accounts for 805 m2 according to PHPP. The solution sets are based on external shading devices, mid-pane blinds and low-gain glazing combined with natural and mechanical ventilation strategies and have been designed to meet the stringent certification requirements.
Moderate ground-coupling with 6cm of XPS below the floor slab helps dissipate heat in the summer, with 16cm of EPS insulation on the roof to limit transmission heat gains. The pre-cast concrete wall panels were externally insulated with 10cm of XPS insulation, and finished with a ventilated polycarbonate façade that is back-lit at night to provide a stunning visual effect.
In particular, the external wall in concrete foam is insulated with 10 cm of EPS and presents a thermal transmittance of 0.288 W/(m2 K), while the roof is insulated with 16 cm of XPS and has a U-value of 0,194 W/(m2 K).
The windows has a double glazing filled with argon and a low-transmission coating that allows to reach a g-value of 27%, limiting the solar gains through the window element and the curtain wall. The thermal performance of the glass is also quite high, since it accounts for 1 W/(m2 K).
The heating and the cooling are supplied by a variable Refrigerant flow LG heat pump, with indoor split units that recirculate indoor air. The ventilation system integrates the heat recovery and particular care has been devoted to the acoustic insulation of the ducts. The domestic hot water is produced by an additional air-source heat pump.
Moreover, the building is equipped with a lighting system with LED components and automatic control and integrates also charging points for electric vehicles in the car park.
The overall performances are significantly below the requirements for having the Passivhaus certification, and in particular the Primary Energy (including heating installation, domestic hot water, household electricity and auxiliary electricity calculated according to PHPP) accounts for 51 kWh/(m2 a), with a limit value of 83 kWh/(m2 a).
Concerning the cooling period, although the severity of the climate, the requirements has been fulfilled, with a load of 14 W/m2 and a cooling and dehumidification demand of 16 kWh/(m2 a).