Energy efficient construction
An important part of living in your new home is a basic knowledge about energy, the energy pass and how to save energy. For years VARIO-HAUS has pursued the concept of developing and constructing homes that are not only totally in accord with the spirit of protecting the climate and the environment but also reduce energy consumption.
First class examples of the innovative abilities of VARIO-HAUS is the first prefabricated passive house VARIO-HAUS del Sole in the year 2000 and the introduction of VARIO-HAUS VISION – the active passive house – in 2010. The photovoltaic system on the roof generates approx. 4,500 kWh power per year. Two thirds of the output is consumed by a four-person-household, the rest can be fed back in the power network or used for a power charging station.
Heat requirement in the future
The future heat demand for residential houses is one the big environment issues for the future, as far as the protection of the climate and the environment is concerned. A higher cost saving efficiency is also imperative.
At the moment we have varying heat demand figures depending on the differing minimum standards set by the building regulations or the qualifications for government building grants.
A standard residential house as defined by Austrian Institute for Building Technology (OIB) reaches an energy index of 66.5 kWh per year at the best, depending on the ratio surface to volume. This corresponds to a heating oil consumption of six to seven litres per sqm and year.
If people want to apply for government building grants their building project must substantially fall below the minimum standards set by the regulations. Proof must be shown by the energy pass (calculated on the basis of the guidelines of the OIB). The index calculated in the energy pass generally corresponds to the heating demand of a residential building and clearly shows how much heat the house requires under standardised conditions.
The energy index of a house is as significant as the average fuel consumption per 100 km of a car. The calculation of the energy index is influenced by the geometry of the house, glass surfaces, the climate and the optimum orientation of the building and the site.
Types of houses according to their energy consumption
In Austria there are huge differences in the energy indexes of residential homes. An old building needs about 15 times more energy than a passive house per year and should be renovated, especially as far as the heat insulation of walls and windows is concerned. A standard house is representative of the minimum requirements for heat insulation. The level of the heat insulation for an energy saving house represents the requirements for building grants (depending on the county in Austria) as far as energy consumption is concerned.
The low energy house is the aspired standard for highly comfortable and ecologically compatible houses, the so called 3-litre-houses (3 litres of heating oil per sqm and year). The passive house is the standard of our millennium. The energy demand comes up to only 15 percent in comparison with a standard house. The reasons are excellent heat insulation and intelligent house installations with heat recovery systems.
