Name and Address
Name of the demo site: NHT IN40
Address of the demo site: Reichenauerstraße 62, 64, 66 in 6020 Innsbruck, Austria
City map highlighting the surface occupied by the demo site (source: http://city-map.innsbruck.gv.at)
NHT finished the innovative overall building renovation, consisting of the thermal renovation of walls, ceiling, roof and windows with triple-glazing. Existing balconies were demolished and replaced with new thermally separated ones. A central, flat-specific ventilation with heat recovery was integrated. The heating system is connected to the district heating network of IKB and was newly installed.
Ownership: Neue Heimat Tirol (NHT)
Gross conditioned floor area (EPC): 4,805 m²
Treated floor area (PHPP): 3,500 m² (without groundfloor)
Number of dwellings: 49
Heating demand (EPC)
BEFORE RENOVATION: 54 kWh/m²*a
AFTER RENOVATION: 22 kWh/m²*a
Heating demand (PHPP)
BEFORE RENOVATION: 81 kWh/m²*a
AFTER RENOVATION: 17 kWh/m²*a
Overall savings after completion of ventilation & heating system: >80%
All objects are patched via 1 long complex.
IN40 stock is a typical building block constructed in the second half of the 20th century with related challenges regarding insulation, electric cables, low performing windows, uninsulated roofs and cellars. The heating system is connected to the district heating network. The building was a Category C in terms of energy performance.
Connected to the district heating network
Energy performance certificate
Thermal renovation of the walls, the ceiling, the roof and the windows with triple-glazing. Balconies were completely replaced by new thermal bridge-free ones. Decentralised, flat-specific ventilation with heat recovery was integrated.
Roof to wall insertion section (thermal bridge)
Ground to wall section (thermal bridge)
Wall to fenestration section (thermal bridge)
The target is to achieve a calculated energy consumption per m² of total used energy per conditioned floor area of about 34.8 kWh/m²*a (Space heating via district heating and DHW with electric hot water boilers).
The refurbishment is financed via a mix of reserves as well as local/ regional/ national/ EU funding and includes an increase of the monthly rent.
11 of the 49 apartments are equipped with flat-specific, decentralised ventilation systems with heat recovery. 22% of the building users are connected to the systems. All other apartments will be upgraded in the event of a change of residence.
Electric renewable integration
Nominal power of PV IN 13: 35.91 kWp, 240m² SOLARWATT modules
Mounting type: Roof mounted parallel
Elevation: 574 m a.s.l.
Azimuth angle: 199°
Financial model: "tenant flow model" -a pilot project in the state of Tyrol
Contracting authority: NHT Neue Heimat Tirol
Project manager: Gerda Maria Embacher
Architect/Envelope Designer: Architekt Vogl-Fernheim
Technical system designer: Klimatherm GmbH, Büro Ing. Obwieser Ges.m.b.H.
Construction company: KPS-Ötztal Putz, C. Günther, Strabag, Bodner, Rohner, Opbacher,
Windows supplier: Alutherm
Energy consultant, scientific support: University of Innsbruck and Passive House Institute – Department Innsbruck
Total investment of € 3,36 Mio.
The challenges in the course of the refurbishment of residential buildings are complex and multi-layered. Financial and social aspects and challenges need to be considered, because the tenant has to co-finance some parts of the renovation, which requires the implementation of persuasion and tenant engagement activities. Furthermore, legal challenges also have to be solved. The most intensive persuasion is to be done in the field of nearly zero energy house renovation and, in particular, in cases where tenants are living in the flats during the time of ventilation system installations and other intrusive renovation activities.
Within SINFONIA, NHT has pushed the installation of controlled ventilation with heat recovery in IN40. For the time being, 22% of the building users have agreed to implement this measure. Further extension is expected according to the fluctuations of the building users and corresponding rental contracts with new tenants.
Prognosis for the renewable energy yearly yield: 37,741 kWh/a
End-Energy use (EPC): Calculated with 69,40 kWh/m²*a
Energy efficiency certificate (EPC): Category A
EnerPHit pre-certificate for stepwise refurbishment (PHI): EnerPHiT certification is foreseen shortly