The standard data for permeability to water vapour of building materials are mostly derived from the steady state 'cup method' (CEN 2001). For highly porous materials, such as fibrous insulation, the value measured in this way is mostly attributable to diffusion through the linked air spaces and takes no account of moisture absorption during changing gradients of temperature and water vapour concentration, which is the natural environment of building materials. The apparatus described here is designed to give direct measurements of the effects of linked diffusion and sorption in a cont inuously changing environment.

::very frank about setup's shortcoming.

Same author and same source: "Non-Isothermal water vapour transmission through porous insulation. Part 2: Measurements"

• measurement: vapor diffusion properties, WVT

1. Humidity buffering of interior spaces by porous,absorbent insulation, part of hygrothermal properties of alternative insulation materials
2. Test cell measurements of moisture buffer effects
3. The role of absorbent materials in moderating changes of relative humidity  

1. International building physics toolbox, general report
2. Investigation of Microclimate by CFD Modeling of Moisture Interactions between Air and Constructions
3. Moisture and bio-deterioration risk of building materials and structuresL?hdesm?ki
4. Moisture buffer value of building materials
5. Moisture Buffer Value of Materials in Buildings
6. Moisture dynamics in building envelopes
7. The International Building Physics Toolbox in Simulink
8. Towards modelling of decay risk of wooden materials  

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. Organic insulation materials: effect on indoor humidity and necessity of a vapor barrier
16. Test cell measurements of moisture buffer effects
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. Experimental investigation of the hygrothermal performance of insulation materials
2. Moisture Buffer Value of Materials in Buildings
3. Results of a water vapor transmission round-robin test using cup methods
4. Sorption isotherms - a catalogues
5. Sorption isotherms: a catalog and a data base