REPOSITORY > RESULTS

Abstract

Buildings are complex systems as external factors are linked to, and have an effect on the
characteristics of a building. In this dissertation, the focus is on the connection between
external factors and the building’s characteristics, which have an impact on the living
conditions, durability and energy efficiency of a building: especially on a low energy
(including passive) building. Passive means of ensuring appropriate indoor temperatures
and relative humidity were studied, as were the impact of different factors on living
conditions and the energy balance of buildings: the thermal and other properties of
construction materials, the type of construction, the heating control system, ventilation,
and solar protection. These were studied using the temperature measurements and relative
humidity profiles of test houses, the energy balance data of test houses and the use of
simulation techniques. The results clearly show that the use of different building
materials, with different thermal properties, specific heat capacities, and densities, results
in differences in conductivity and heat transference, which has an impact on the external
and internal conditions of a building, which in turn, have an impact on comfort and
energy consumption, especially during transitional periods. The heating control system of
a building also has an important impact on thermal comfort. High ambient temperatures
and strong solar radiation during the summer months can lead to overheating in lowenergy
houses, which due to their good insulation have limited ability to lose heat into the
environment. In climates with large differences between their highest and lowest daily
temperature (15 K), it is possible to keep internal temperatures in low-energy houses
within the comfort zone with cooling through -windows at night and the effective shading
of windows during the day. Indoor humidity levels can be kept within the comfortable
range with the use of vapour retarders and hygroscopic insulation materials. By these
means, excess moisture, produced by the activities of people, can be released through the
thermal envelope of a building and temporarily absorbed in the hygroscopic building
materials. Otherwise, humidity levels can rise too high and have a negative impact on the
health of occupants or cause structural damage to the building with consequences on its
durability. Therefore, there are many external and internal factors related to the
characteristics and properties of a building that have a direct impact on a building’s
durability, energy efficiency, and the degree of comfort it provides to its occupants. When
planning a low-energy building, all components must be optimized and hygrothermal
processes and the properties of the materials taken into account to ensure a high level of
energy efficiency and comfort. It is practical to regulate temperature and humidity levels
using materials with a high thermal capacity and good hygroscopic and moisture diffusion
properties. There is reduced pressure on a building’s heating and ventilation system if
these passive means are used to keep living conditions comfortable. Careful planning
should result in a house that is healthy, functional, and comfortable, and which provides
protection from external elements while having a low impact on the environment.