Hygrothermal modeling is, in many countries, either required by code or has become an industry standard. Awareness of the required inputs has also been improved. Reasonable boundary conditions are necessary to obtain representative results for the hygrothermal simulation of building components. Furthermore, realistic assumptions for hygric and thermal loads for wholebuilding simulation are required to assess the practical building performance. This means that all boundary conditions need to be appropriately defined for each specific design application.
Standards that define internal boundary conditions for hygrothermal building component simulation are reviewed. These standards define deterministic input values. Realistic values for indoor temperature and relative humidity were obtained by measuring the conditions inside residential buildings in two different climate zones. For the assessment of the influence of the location within the building, in average five rooms per building were equipped with data loggers to continuously record the conditions.
These realistic conditions are analyzed. The density distributions of the measured values are used first to describe probabilistic input data for hygrothermal simulation and secondly to assess possible dependencies regarding the positioning in the building. It is shown that dividing the data into seasonal subgroups allows representation of the data per location as normal distributions. This is a first step in describing nondeterministic input values for hygrothermal simulation.
The found conditions are compared to the conditions assumed by using the standards. It is found that there are deviations between code-based internal boundary conditions and measured conditions. These differences may lead to wrong results in hygrothermal building component assessment and hygrothermal whole-building simulation.
Citation: Thermal Performance, International Conference, 2010
Product Details
- Published:
- 2010
- Number of Pages:
- 11
- File Size:
- 1 file , 2.8 MB
- Product Code(s):
- D-BUILDINGSXI-133
