Hygrothermal Building Analysis

Fraunhofer Institute for Building Physics

Hygrothermal Building Analysis

The work group »Hygrothermal Building Analysis« examines the hygrothermal performance and interaction of the building envelope and the enclosed space. The achieved insight is used to develop and apply a hygrothermal whole building simulation tool. An integral consideration of all boundary conditions influencing the hygrothermal building performance allows a detailed analysis with regards to energy use, indoor environment and the hygrothermal conditions in the building envelope.

This includes monitoring, compiling and evaluation of boundary conditions like inner heat and moisture loads, air exchange, measured and modelled weather data sets but also user behaviour regarding set-point operation or window opening in different climate zones. The incorporation of the acquired knowledge in the hygrothermal whole building simulation software WUFI®Plus allows a fast praxis transfer.

Competences

Hygrothermal Building Monitoring

Hygrothermal issues in buildings are often influenced by more than one factor. Mould growth for example can occur due to critical detail solutions, a high moisture production in the room, insufficient ventilation or a combination of several factors. The scientists of the work group »Hygrothermal Building Analysis« records temperature and humidity conditions as well as the user behaviour and assess them. This allows the development of solutions to avoid critical conditions, to improve the hygrothermal comfort and to reduce the energy use of the building.

Model development and experimental validation

Besides energy related analysis hygrothermal building simulation allows the assessment of the indoor environment and to assure a damage free construction. To perform realistic simulations it is on the one hand necessary to represent physical relationships in best possible detail. On the other hand models need to be developed, which take into account e.g. windows, thermal bridges, user behaviour or air exchange in a simplified but sufficiently accurate way. Models are developed based on theoretical relations and measurements in laboratory under realistic conditions. In a next step these models are implemented in the WUFI®Plus software.

Hygrothermal Whole Building Simulation Studies

Connecting hygrothermal building component analysis with whole building energy simulation allows the development of integral solutions, considering the conditions in rooms and components and their interaction without neglecting the influence of different approaches on energy use. In this way not only adjusted strategies for residential and office spaces can be developed, but for example also passive measures to ensure a stable climate in historic buildings. With the existing simulation environment the influence of different climate zones, building uses, component assemblies with varying materials, geometries and orientations as well as different building operation strategies on indoor environment, energy demand and durability can be evaluated in detail. Based on those investigations refinement strategies may be developed that concentrate on the most efficient and cost effective improvements.

Knowledge Transfer into Practice

Research results and their interpretation are made available for the building science community as well as for building practitioners by presentations and publications in national and international conferences and journals. Furthermore it is integrated in the hygrothermal whole building simulation software WUFI®Plus. The intention is to provide the architect or engineer with a tool that allows not only comprehensive simulations and analysis but also good usability. The documentation of the software features, the compilation of training material and the conduction of seminars prepares the gathered know-how for practical use.

Building Concepts for New Markets

Energy efficient building concepts for growth markets in e.g. Asia are adapted to compact urban building techniques and different climatic boundary conditions. Measures to maximise comfort by simultaneously reducing the fossil energy use are evaluated through hygrothermal building analysis. Furthermore building products and systems are developed together with industrial partners, which are cost-effective and provide besides technical quality also an added value by better service for the users and improved standard of living.