Buildings are constructed of hygroscopic materials and are simultaneously exposed to both large temperature and humidity gradients. If accurate computer predictions of the combined transfer of heat and moisture in building construction are to be made, then it is essential that theory be developed and experimentally verified. The objective is to advance the state of the art for predicting moisture transfer and storage in buildings by formulating moisture transfer theory, upgrading existing experiment, and measuring moisture transfer through a typical material under isothermal and isothermal conditions.

Principal Investigator:William Thomas, Virginia Polytechnic Institute

Conducted:April 1994 - January 1997

Sponsored by:TC 4.4, Thermal Insulation and Moisture Retarders

• coupled heat and moisture calculations
• moisture transport in porous materials

1. Advanced Energy Design Guides
2. ANSI/ASHRAE Standard 140-2001, Standard Method of Test for the Evaluation of Building Energy Analysis Computer Programs
3. ASHRAE 52.2, method of testing general ventilation air-cleaning devices used for removal effciency
4. ASHRAE Handbook-Fundamentals
5. BSR/ASHRAE Standard 55-1992R, thermal environmental conditions for human occupancy, first public review draft
6. Characterization of framing factors for low-rise residential building walls
7. Modeling two and three-dimensional heat transfer through composite wall and roof assemblies in hourly simulation programs
8. Position documents: indoor air quality
9. Recommended practices for controlling moisture in crawl spaces
10. Standard 62.2, Ventilation and Acceptable Indoor Air Quality in Low-Rise Residential Buildings
11. Standard 62.2P, Ventilation and Acceptable Indoor Air Quality in Low-Rise Residential Buildings
12. Standard 90.1: Energy efficient design of new buildings except low-rise residential buildings
13. Standard 90.2, Energy Efficient Design of New Low-Rise Residential Buildings
14. Thermal environmental conditions for human occupancy, ASHRAE Standard 55-2004
15. Thermal performance of the exterior envelopes of buildings IV
16. WYEC2 Software