Humidity in indoor spaces is one of the most important factors influencing indoor air quality. Many health related problems in the indoor environment e.g. the Sick Building Syndrome (SBS), can be associated with high indoor humidity and "damp buildings" (Clausen et al., 1999). The humidity level in a building depends on a combination of factors such as moisture sources, ventilation and air movement, reservoirs and sinks, heating, insulation, external conditions, as well as building materials and occupants. Among these, the moisture buffering effect of the materials in a building is an important factor. There is a general interest in exploiting the moisture buffering effect of building materials, such as wood, to dampen the cyclic excursions of indoor humidity. However, this effect is often disregarded by building designers and engineers.

Today it is possible to make computational predictions of the thermal conditions in buildings, and to calculate the heat and moisture conditions in building components when the indoor climate exposure is known. But little effort has been made to develop "complete" hygrothermal models that predict simultaneously the indoor hygrothermal conditions and those of adjacent building components and furnishings. However, one such development, BSim2000, is reported in another paper in these proceedings (Rode et al., 2001). There is a great need to experimentally verify the predictions of whole building hygrothermal models. Some relevant experimental investigations are reviewed by Mitamura et al. 2001 and by Virtanen et al., 2000. In this paper we describe an experiment using a full-scale test cell to investigate the moisture buffering effect of building materials. The results are used both to characterise the buffering capacity of different materials and to verify predictions of a numerical model. The term "moisture buffering effect" will be used to indicate the ability of building materials to decrease humid ity variations in indoor spaces.

• Whole building HAM: models

1. eds. Annex 41 Final Report, Volume 1: Modelling Principles and Common Exercises
2. Empirical validation of a transient computer model for combined heat and moisture transfer
3. Experimental investigation of the hygrothermal performance of insulation materials
4. Full-scale testing of indoor humidity and moisture buffering in building materials
5. Global building physics
6. International building physics toolbox, general report
7. Investigation of Microclimate by CFD Modeling of Moisture Interactions between Air and Constructions
8. Latent heat flow in lightweight roofs and its influence on the thermal performance of buildings
9. Model and experiments for hygrothermal conditions of the envelope and indoor air of buildings
10. Moisture buffer value of building materials
11. Moisture Buffer Value of Materials in Buildings
12. Moisture buffering of building materials
13. Moisture conditions of non-ventilated, wood-based, membrane-roof components
14. Moisture: its effects on the thermal performance of a low-slope roof system
15. Non-isothermal water vapour transmission through porous insulation. Part 1: The climate chamber
16. Organic insulation materials: effect on indoor humidity and necessity of a vapor barrier
17. The importance of moisture buffering for indoor climate and energy conditions of buildings
18. The International Building Physics Toolbox in Simulink
19. The self-drying concept for flat roofs
20. Tools for performance simulation of heat, air and moisture conditions of whole buildings
21. Whole-building Hygrothermal Simulation Model  

1. Full-scale testing of indoor humidity and moisture buffering in building materials
2. Model and experiments for hygrothermal conditions of the envelope and indoor air of buildings  

1. Full-scale testing of indoor humidity and moisture buffering in building materials  

1. Humidity buffering of interior spaces by porous,absorbent insulation, part of hygrothermal properties of alternative insulation materials
2. Non-isothermal water vapour transmission through porous insulation. Part 1: The climate chamber
3. The role of absorbent materials in moderating changes of relative humidity