A very special wooden house is located in the middle of a flowering meadow in the Dachau hinterland. It was built in 2011 using spruce, larch, pine and birch wood – without the utilisation of chemicals or artificial tools. Featuring a photovoltaic system, solar energy, a heat pump and intelligent building technology from Gira, the result was a house which is ideally ecological and yet healthy, convenient and nearly zero-energy. It produces more electricity than it consumes.
When searching for a wooden house supplier, the owner encountered Erwin Thoma and his company. He constructed the building only of wood, without glue, screws or nails. The walls, ceilings and roof consist of wooden elements which are up to 40 cm thick − they are a combination of spruce and pine. Rugged larch wood was used for the façade and the windows. Floors and door frames are made of ash trees, while the stairs and bench under the window are walnut. In brief, almost the entire range of native tree types was integrated.
The special highlight: the boards and beams were layered horizontally, vertically and diagonally to the structural elements. They are connected with extremely dry beechwood plugs which take on moisture when positioned. They then swell to form a stable joint. This resulted in an absolutely healthy home with convincing ecological characteristics. The thermal insulation of wood is also impressive. Thick solid wood walls keep the house cool in summer and warm in winter. It also offers better noise and fire protection than a home with a conventional brick or reinforced concrete construction.
Planning and design The house is also on the cutting edge regarding building technology. While doing Internet research on intelligent systems in advance, the owner discovered the international KNX standard. Then he visited Anton Hieber at the Gira Revox Studio in Augsburg to look at solutions and try them out. Because the owner didn't want to use any plastics in his new home, he decided on the Gira E22 switch series made of stainless steel, which is a distinctive contrast to the wood and glass. Anton Hieber and his company were responsible for the entire planning and programming of the home technology, while Elektro Ernst was commissioned with the installation. This collaboration was extremely smooth.
Installation Today a powerful KNX system links all of the electric components in the home. The Gira HomeServer is the intelligent central control unit in the background, where all of the information merges and is analysed. For example, heating, lighting and sliding shutters are integrated in the system. The temperature can be set individually for each room. At the press of a button, entire light scenes are called up on the Gira push button sensors. Switchable socket outlets and standard lamps are also integrated. The light in the hallway is activated using motion detectors, while Gira flush-mounted radios set a positive mood in the kitchen and bathrooms.
The "central off" function is also clever, according to System Integrator Anton Hieber. "Using this function, the owner can switch off all energy consumers at the press of a button when leaving the house. In addition, thanks to the installed window contacts, he can see whether and where a window is open." The home technology is controlled via the Gira Interface on an iPad, iPhone or office PC.
Conclusion A photovoltaic system is installed on the roof facing south. This system generates approximately twice as much electricity as the owner consumes in his home. A solar thermal system is installed on the south wall of the garage to heat the service water. A piping system was laid below 700 m² of the flowering meadow – this collector is coupled to the geothermal energy pump and heats the home. Particularly clever: excess solar energy is guided to the ground, which makes the heat pump run even more efficiently. This makes the owner's life healthy and ecological, as well as nearly zero-energy. Logically, he is considering an electric car for the future.