Annex 41

Whole Building Heat, Air and Moisture Response (MOIST-EN)

Coordinator: Professor Hugo Hens, K.U. Leuven, Belgium

Annex 41 of the International Energy Agency’s (IEA) Energy Conservation in Buildings and Community Systems program (ECBCS) was a cooperative project. It ran from 2003 to 2007 and is completed. The project aimed to acquire a better knowledge of whole-building heat, air and moisture balance and its effects on the indoor environment, on energy consumption for heating, cooling, air humidification and air drying, and on the envelope’s durability. The research follows on from “Condensation and Energy” (Annex 14), “Heat, Air and Moisture Transport in Insulated Envelope Parts” (Annex 24) and “Integral Building Envelope Performance Assessment” (Annex 32).

The research work was divided into four sections: 1) Modelling principles and common exercises, 2) Experimental investigations, 3) Boundary conditions, and 4) Long term performance and technology transfer.

The project had two main objectives:

  • A detailed exploration of the complex physics involved in whole building heat, air and moisture response (HAM-response). This included basic research, a further development of existing and new models, measurement of the moisture storage function of materials, measurement of the air permeance of envelope parts as built, mock up testing, field testing and validation by inter-comparison of models through common exercises and confrontation with measured data.
  • An analysis of the effects of the whole building HAM-response on comfort, enclosure durability and energy consumption.

Participants: Austria, Canada, Belgium, Brazil, Denmark, Estonia, Finland, France, Germany, Israel, Japan, Netherlands, Norway, Portugal, Sweden, Slovakia, Spain, Switzerland, UK, and USA.

Publications and reports of the project