Heat, Air and Moisture Transport

Completed (1991 - 1995)


The objectives of this annex were to model and study the fundamental physical phenomena behind and the consequences of heat, air and moisture transfer through new and retrofitted insulated envelope parts. A special emphasis will be put on the energy quality, depending on air tightness, on the hygric behaviour and on the durability aspects of the construction. The knowledge gained by this analysis was applied to performance formulation and to checking the design and production of new retrofitted parts. It was divided into the following five subtasks:

Subtask 1: Model and Algorithm Development

This task includes improving modelling techniques and testing simplified models for predicting the combined effects of HAM-transport on insulation quality, hygric behaviour and durability.

Subtask 2: Inside and External Environmental Conditions

This task includes selecting environmental parameters and a methodology of handling them and the development of exemplary sets of environmental conditions.

Subtask 3: Material and Layer Properties

This task includes data collecting on thermal hygric and air properties of materials and layers and substantial fresh measuring work, especially on the moisture and air properties.

Subtask 4: Experimental Verification

Experimental verification includes hot box and field tests on HAM- transport in envelope parts and comparing measurement results with model prediction.

Subtask 5: Performances and Practice

This task Includes the translation of HAM-knowledge in correct design and execution of highly insulated new and retrofitted envelope parts.

Operating Agent

Prof Hugo Hens
K.U. Leuven
Department of Civil Engineering
Laboratory of Building Physics
Kasteelpark Arenberg, 51
B-3001 Leuven
Tel: +32 16 32 13 44


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