Key design elements and achievements
The new LichtAktiv Haus design retained the basic structure of the existing building while adding a modular extension and applying new materials and energy-efficient technology.
Daylighting design played a central role in the architectural concept of the LichtAktiv Haus, as daylight is vital to our biological rhythm and has a positive impact on our well-being and performance. Optimised, controlled daylight use also reduces the need for artificial lighting and provides useful solar gains during the winter period, significantly reducing the building’s energy consumption.
The LichtAktiv Haus project team worked with lighting designer and professor Peter Andres, using extensive daylight analyses in the early project design phase and integrating them in the dynamic process of building planning. As a result, the LichtAktiv Haus’ kitchen, dining areas and bedrooms have an excellent average daylight factor (DF) of 5% or more, while the living area has an average DF of over 10%, meaning no artificial lighting is needed during a typical day.
High amounts of daylight and generous views enable the family to fully experience the daily rhythms and seasonal changes of their surroundings. Awning blinds, on the other hand, allow them to adjust the amount of incoming daylight, prevent glare and overheating – and create a flexible, comfortable environment.
Automated, natural ventilation
Despite its lack of a heat recovery system or central air conditioning, which are often too costly to implement in older homes, the LichtAktiv Haus is able to achieve carbon-neutrality. Here, the home’s automated roof windows make a remarkable contribution by providing natural ventilation.
Together with shutters and sun screening products, the ventilation concept works as natural air conditioning. During warmer periods, the south-facing shutters remain closed at midday. On the western side, the external awnings automatically lower in the afternoon. As the day gets cooler, the shutters and awnings are raised and the windows opened to let the fresh evening air cool down the living space.
During cooler months, the shutters stay up during the day to allow passive solar heat to warm the home, closing at dusk to keep the heat inside. Automatically controlled roof windows eliminate the need for a ventilation shaft. And, depending on the home’s temperature and humidity and CO2 levels, a solar-powered control system automatically opens and closes the windows to ensure a comfortable, healthy indoor climate at all times.
Following a core Active House principle, the LichtAktiv Haus covers its entire energy demand, including household electricity, by using renewable energy – without losing any of its high living values such as daylight and fresh air. This is particularly challenging to achieve when renovating older homes as they often have much higher energy demands.
An air-water-heat pump and 22.5 m² of solar collectors work together to supply the home with heat and hot water. This highly efficient technology reduces greenhouse gas emissions by minimising the need for conventional energy. The home’s 75 m² of polycrystalline photovoltaic (PV) cells on the roof power the heat pump and also act as a source of environmentally friendly electricity.
Along with water-saving fixtures throughout the house, the LichtAktiv Haus is also equipped with water collectors that supply rainwater for the washing machine, toilets, and garden watering.