The Austrian concern Baumit International is known in Europe as a leading manufacturer of products for facade decoration. The company, whose history began in 1810 with a limestone kiln, is today one of the leaders in the production of building materials. The mission of the company is “to make living spaces safe for health, energy efficient and beautiful”.
In a quest to improve building materials and study their effects on humans, in 2014, Baumit's R&D department launched a unique project to create the Viva Research Park. And already in 2015, 10 experimental houses were built on the territory of the new Baumit center in Wopfing. For two years in real time and changing weather conditions, they were to be monitored by employees of the research institute.
In terms of proportions, the built houses are absolutely identical: one room 3x4 m, ceiling height - 2.8 m, flat roof, one window without curtains and one front door. At the same time, different materials were used for the construction of houses - both for the frame and for external and internal finishes. Also, different thermal insulation systems were used.
For example, two concrete houses were built with different interior finishes. Brick houses - with and without thermal insulation. Houses with the same lightweight timber frame, but different wall finishes. Monolithic buildings clad with 50-inch slabs with internal thermal insulation. And also houses made of solid wood.
Inside each house, it was possible to reproduce the real operating conditions - as if in the room someone was constantly preparing food, taking a shower, opening and closing the front door, ventilating, etc. To monitor any changes in physical parameters, 33 sensors were installed in each house. Throughout the day, they recorded indicators of heat preservation and protection against overheating, moisture buffering, temperature fluctuations of internal surfaces, odor intensity, sound insulation and acoustic properties, etc. Even the air ions, the concentration of gases and the amount of dust deposited on internal surfaces in one day were in the focus of attention. All data was transmitted daily to the institute for further analysis.
More than five million indicators were analyzed in two years. Experts from various fields were involved - specialists from the Vienna Medical University, the Austrian Institute of Building Biology and Ecology (IBO), the Burgenland University of Applied Sciences (FH Burgenland).
In addition, about 200 people visited each house during the experiment. They were all amazed at how different their sensations were: everywhere it smells differently, sounds are heard differently, the same air temperature and humidity are felt differently. Even the perception of space is changing.
Experts at Baumit evaluated the experimental homes primarily in terms of human health and safety. The answer was unambiguous - structures and finishing materials have a huge impact not only on the perception of space, but also on the physical and psychological state of the tenant. They form the microclimate, determine the air quality in the room, and, accordingly, are responsible for the well-being of the person in this space.
Research has shown that the most favorable microclimate in a home is created by three main factors:
- massive walls;
- breathable thermal insulation;
- mineral plaster for interior decoration with a layer of 1.5 - 2 cm.
Massive walls
Walls are a buffer to store energy in a building. Only heavy, massive walls can smooth out temperature fluctuations and thereby increase the energy efficiency of the house. In winter, such walls keep warm, and in the hot season they keep the interior cool.
In the summer of 2015, at the time of the study, extremely high temperatures were recorded in Austria - up to 36 ° C. But even in such heat in houses with massive walls and thermal insulation, a comfortable air temperature remained, on average - 26 ° C. The walls stored heat during the day and released it at night. Due to this, the temperature inside remained practically unchanged.
The most stable microclimate without significant temperature changes was provided by houses made of bricks and plaster. Almost the same indicators are found in concrete buildings, which also gave the best protection against noise and electrical smog. We managed to maintain a favorable climate in the houses made of solid wood. They also received the best acoustics. But in buildings with a light timber frame, the opposite effect was observed: during the day it became very hot in the room - up to 30 ° C, and at night it was quite cool.
Thermal insulation
Thermal insulation is of no less importance for maintaining a stable microclimate. In warm seasons, thermal insulation protects the building from overheating. In the hot summer of 2015, the temperature difference between insulated and non-insulated houses reached 5 ° C.
In order to evaluate the properties of the applied thermal insulation in winter, the following experiment was carried out. Heating was turned off in all 10 houses for two days. At the time of shutdown, the indoor temperature was 21 ° C and the outdoor temperature was –12 ° C. After 2 days in an uninsulated house, the temperature dropped to 4 ° C. Whereas in houses with thermal insulation it remained at the level of 15-17 ° C.
Measurements have shown that 60% less energy was used to maintain the temperature at 21 ° C in insulated houses than in non-insulated ones.
Interior decoration
Klima interior plaster maintains indoor humidity at a comfortable level of 40-60%, and also reduces the risk of developing harmful microorganisms. For this, a small layer of plaster 2 cm thick is enough.
On the Viva experimental site, two concrete houses were built, one with KlimaPutz interior plaster and the other with uncoated walls. In the latter, the air humidity varied in a significant range between 30% and 70%. At the same time, in a house with plastered walls, the humidity remained at the most comfortable level of 40-60%.
Research in Europe's largest research park continues today. In 2018, two more houses were built on its territory. And now they are being actively monitored in search of the best solutions for the life and health of people.
