Residencial Vía Verde is a multi-family housing development in Valdefierro, made up of 137 dwellings. Cross ventilation is guaranteed by the orientation of the dwelling in two different directions.

Aerothermal energy has been installed for the production of heat, meaning that dwellings are using only electricity and are not dependant on gas or other fossil fuels.

Thermal envelope

Exterior wall: The building envelope is composed of 2 different dry construction systems, which replace the main masonry leaf and improve the thermal performance of the wall up to U-values of 0.21 W/(m²K) with reduced façade thicknesses of 20 cm.
U-value = 0.21 W/(m2K)

Basement floor / floor slab: The first floor slab uses a conventional concrete solution, with 12 cm thick expanded polystyrene (EPS) on the one-way slab and 3 cm of EPS on top to complete the underfloor heating installation, obtaining a U-value of 0.2 W/(m²K).

Roof: The flat roof is built with a conventional one-way slab, with 16 cm of XPS insulation on the outside, obtaining a U-value of 0.24 W/(m²K). In the double height area of the attics, the enclosure is a sloping metal structure roof, composed of a sandwich panel of 10cm of rock wool, air chamber, and a second sandwich panel finished with 3cm of PUR, which also acts as an exterior finish. The U-value obtained in this enclosure is 0.26 W/(m²K).
U-value = 0.24 W/(m2K)

Mechanical systems

Ventilation: An individual double-flow ventilation system with heat recovery programmed with three speeds within the PHI certified flow rate range has been installed. The unit is located outside the thermal envelope to avoid the presence of continuous noise in the home, a particularly sensitive aspect in the perception of comfort. Consequently, the connection ducts between the heat recovery unit and the dwelling are duly insulated and the loss of performance of the unit is included in the overall energy balance. Continuous ventilation achieves excellent indoor air quality.

Heating installation: For heating and cooling, aerothermal units have been used, accredited with the first certification of an air-to-water heat pump as a Passivhaus component on the market.
Underfloor heating has been used as the terminal unit.

The building has domestic hot water with collective production by means of 6 high temperature aerothermal units with an integrated 726 litre tank and two accumulation tanks of 3,500 litres each.

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