Linz - Planning Measures in a Team

This was the first project in Austria using transparent thermal insulation. This is a special insulation system reducing the loss of energy through the walls and leading sun radiance through the walls into the room. Renovation was based on planning the measures in a team.

Multi-family Home From the 60-ies
The renovation example Linz is a multi-family home built in the mid-60-ies. The four-storied building has 52 rental flats, 4 x 660 m2 floor-space and approx. 1,700 m2 outside wall space (windows excluded).

Facade Plastering Damages
Chipped-off facade plastering triggered renovation efforts in September 1995.

Improving Thermal Insulation

• replace window glasses (k-figure = 1.1 W/m2.K);
• improve thermal insulation of basement ceiling (10 cm thermal insulation);
• improve thermal insulation of top floor ceiling (20 cm thermal insulation);
• improve thermal insulation of facade (10 cm thermal insulation panels; 120 m2 transparent thermal insulation).

50% Reduction of Thermal Energy
Transparent thermal insulation was planned by Oberoesterreichischer Energiesparverband (Upper-Austria energy conservation association) and Sto AG. Based on the exact calculation of thermal energy requirements renovation measures were defined which resulted in a possible reduction of thermal energy by 50% consumption. Another 5%-reduction was achieved by the additional application of a transparent thermal insulation system, saving 2,800 kWh per year.

Based on the building's orientation and given facade- and window-areas, a total of approx. 120 m2 of transparent thermal insulation system were mounted, approx. 40 m2 on the south-east facade, approx. 53 m2 on the south-west facade and approx. 27 m2 on the north-west facade.

The energy key figure was 150 kWh/m2 before renovation and 50 kWh/m2 after renovation.

The following pages portray the individual steps of renovation highlighting specific features of the project and pointing out ecological aspects and future perspectives of skilled trades.