This paper discusses three different multi-layer unit specimen installed in a calibrated hot box, The exterior surfaces of the wall specimens were first exposed to both Steady and time-dependent winter conditions, while their interior surfaces were maintained at 21*C (707) and 50% relative humidity. 7hese boundary conditions caused moisture from the interior environment to permeate into the wall specimens and accumulate in their exterior construction materials. Subsequently, the exterior air temperature was elevated to 32*C (904T), and the exterior construction materials lost moisture to the interior environment. 77w moisture content within the exterior construction materials and the heat transfer rate at the inside at the surface of wall specimens were measured and compared to computer predictions. 77x moisture and hew transfer proper tLes for the construction materials comprising the wall mens vx-re independently maward and used as input to the computer Model.

The agreement between predicted and measured moisture contents was within 1.1% moisture content. Predicted and measured heat transfer rates also were in close agreement. Accumulated moisture U14S OWrVed to have fittk Od on heat transfer because moisture did not accumulate above the hygroscopic limit (ie., the sa-caWfavr saiwation point) and capithuy water did not exist within the pore space of the materials. The insulation renudned relatively dry, and the boundary conditi,ms did no give rise to a Went heat effect (ie., water was not induced to evaporateftm one part of the construction and condense in another part)

• experiment: laboratory
• validation of models : validation of MOIST

1. A computer analysis of the moisture performance of roof constructins in the U.S. DOE Moisture Control Handbook
2. A mathematical analysis of moisture and heat transfer in the roof cavities of manufactured housing
3. A prarmeteric study of wall moisture contents using a revised variable indoor relative humidity version of the "MOIST" transient heat and moisture transfer model
4. An analysis of moisture accumulation in the roof cavities of manufactured housing
5. Computer analysis of wall constructions in the moisture control handbook
6. Empirical validation of a transient computer model for combined heat and moisture transfer
7. Heat and moisture transfer in wood-based wall construction: measured versus predicted
8. Indoor ventilation requirements for manufactured housing
9. Manufactured housing walls that provide satisfactory moisture performance in all climates
10. MOIST: A PC program for predicting heat and moisture transfer in building envelopes, Release 3.0
11. Water vapor permeability measurements of common building materials
12. Water vapor sorption measurements of common building materials
13. Water-vapor measurements of low-slope roofing materials  

1. Heat and moisture transfer in wood-based wall construction: measured versus predicted
2. NIST/NRC-Canada interlaboratory comparison of guarded hot plate measurements: 1993-1997  

1. Evaluating building integrated photovoltaic performance models
2. Heat and moisture transfer in wood-based wall construction: measured versus predicted
3. Prediction of Building Integrated Photovoltaic Cell Temperatures
4. Test procedures for advanced insulation panels
5. Water vapor permeability measurements of common building materials