Abstract:Rainwater penetration is the source of moisture that causes the greatest damage to building envelope assemblies. The building envelope should be designed to reduce the amount of rainwater penetration by deflection and drainage. Since it is not realistic to assume a perfect wall without any leakage, the envelope should have the drying capacity to tolerate defects that may arise from the design, construction, and aging of the exterior wall system. Systems with a greater capacity to evacuate moisture from the stud cavity are less likely to undergo moisture damage. A new testing method is developed and deployed to evaluate the relative drying capacity of six wood-framed wall panels of different configurations built into a test hut and tested within a large scale environmental chamber. The wall panels used plywood, oriented strand board (OSB), or fiberboard as sheathing, but did not include cladding. A uniform moisture source was introduced in a water tray set on a load cell at the bottom of each stud cavity. The protocol is based on the hypothesis that the potential for moving a water molecule from the bottom plate to the exterior of the stud cavity is independent of the previous journey of that molecule, i.e., whether it has traveled from the interior of the bottom plate to the surface of the plate or whether it comes from free water in a tray at the level of the bottom plate. For a given set of boundary conditions, this potential is a function of the characteristics of the wall panel, and is identified as the drying capacity of the panel or its drying by evaporation index (DEI). The value of DEI corresponds to the evaporation rate. The moisture response of wall materials enclosing the stud cavity and the evaporation rate of the moisture source were monitored. The results show that this index can be used as an indicator of the relative drying capacity of different wall systems.

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• experiment: hygrothermal -- large scale laboratory testing
• experiment: hygrothermal performance

1. A limit state design (LSD) approach for comparing relative drying performance of wood-frame envelope systems with full-scale lab, A roadmap towards intelligent net zero- and positive-energy buildings,
2. A new test method to determine the relative drying capacity of building envelope panels of various configurations
3. A new testing method to evaluate the relative drying performance of different building envelope systems using water trays
4. A quantitative study for the measurement of driving rain exposure in the Montr¨¦al region
5. A review of research activities in energy efficiency in buildings in Canada
6. Airtightness testing and air flow modeling of two and three-unit multifamily buildings
7. Airtightness testing of two- and three-unit buildings with a single fan
8. Approach for the simulation of wetting due to rain infiltration for building envelope testing
9. Approach for urban driving rain index by using climatological data recorded at suburban meteorological station
10. Behavior of wall assemblies with different wood sheathings wetted by simulated rain penetration
11. Building Physics: 3rd International Conference in Building Physics
12. Building pressurisation can affect possibility of mould growth
13. Cavity pressure in rain screen walls
14. Comparaison de m¨¦thodes de mesure de flux de chaleur pour sp¨¦cimens de grandes et moyennes dimensions
15. Continuous folded plate structures under uniform load
16. Creative case adaptation for building engineering design
17. Design and construction of an environmental chamber facility
18. Design Methodology of Solar Neighborhoods
19. Development of experimental procedure to evaluate potential movement of mold spores from wall cavity to indoor environment
20. Development of HAM tool for building envelope analysis
21. Effect of capillarity on rainwater penetration in the building envelope
22. Environmental chamber for investigation of building envelope performance
23. Essai sur les toits plats isol¨¦s ¨¤ la fibre de cellulose
24. Evaluation of radiance's genBSDF capability to assess solar bidirectional properties of complex fenestration systems
25. Experimental evaluation of potential transport of mold spores from moldy studs in full-size wall assemblies
26. Experimental setup for the study of air leakage patterns
27. Experimental study of temperature distributions across two curtain wall systems
28. Folded sandwich plate structures
29. Identification and transport investigation of microbial volatile organic compounds in full-scale stud cavities
30. IFC-based framework for evaluating total performance of building envelopes
31. Impact of added insulation on air leakage patterns
32. Impact of air leakage pattern on reinsulated walls
33. In-cavity evaporation allowance--A drying capacity indicator for wood-frame wall system
34. Influence of air space on multi-layered material water vapor permeability measurement
35. Influence of facade geometry on weathering
36. Integrated analysis of whole building heat, air and moisture transfer
37. Interzonal air and moisture transport through large horizontal openings in a full-scale two-story test hut: Part 1 - Experimental study
38. Interzonal air and moisture transport through large horizontal openings in a full-scale two-story test-hut: Part 2- CFD study
39. Large scale testing of two flat roof assemblies insulated with cellulose
40. Mapping of air leakage in exterior wall assemblies
41. Measuring air leakage characteristics with flexible double air chambers
42. Measuring air leakage of full-scale curtain wall sections using a non-rigid air-chamber method
43. Methods for the assessment of moisture content of envelope assemblies
44. Modeling of moisture behavior of wood planks in nonvented flat roofs
45. Modelling of indoor air humidity: the dynamic behaviour within an enclosure
46. Moisture buffering capacities of five North American building materials
47. Moisture performance of leaky exterior walls with added insulation
48. Nonlinear elastic analysis of panelized shear sandwich walls
49. Numerical investigation of the influence of room factors on HAM transport in a full-scale experimental room
50. Performance evaluation protocol for full-scale wood-frame building envelopes
51. Potential of rain screen walls to prevent rain penetration: pressurized cavity principle
52. Quantitative driving rain exposure on a vertical wall at various Canadian cities
53. Rapport Final Projet Site Internet - L'enveloppe du batiment et l'efficacit¨¦ ¨¦nerg¨¦tique
54. Review and framework for large-scale laboratory studies on wetting and drying of building envelopes
55. Study of the reduced impact of thermal bridges in two sprayed-applied polyurethane wall assemblies
56. Study on thermal performance of curtain walls using infrared thermography
57. Testing of flat roofs insulated with cellulose fiber
58. The dynamic modelling of air humidity behaviour in a multi-zone space
59. Transfer of heat, moisture and air through metal curtain walls
60. Transient model for coupled heat, air and moisture transfer through multilayered porous media
61. Use of an environmental chamber to investigate large-scale envelope specimen hygrothermal performance  

1. A limit state design (LSD) approach for comparing relative drying performance of wood-frame envelope systems with full-scale lab, A roadmap towards intelligent net zero- and positive-energy buildings,
2. A new test method to determine the relative drying capacity of building envelope panels of various configurations
3. A new testing method to evaluate the relative drying performance of different building envelope systems using water trays
4. Effect of capillarity on rainwater penetration in the building envelope
5. Experimental Determination of Drying Capacity of Wood-Frame Envelope Systems for Comparative Studies and Limit State Design
6. In-cavity evaporation allowance--A drying capacity indicator for wood-frame wall system  

1. Building Physics: 3rd International Conference in Building Physics
2. Building pressurisation can affect possibility of mould growth
3. Experimental study of temperature distributions across two curtain wall systems
4. Measuring air leakage characteristics with flexible double air chambers
5. Measuring air leakage of full-scale curtain wall sections using a non-rigid air-chamber method
6. Study on overall thermal performance of metal curtain walls
7. Study on thermal performance of curtain walls using infrared thermography
8. Transfer of heat, moisture and air through metal curtain walls  

1. A new test method to determine the relative drying capacity of building envelope panels of various configurations
2. A new testing method to evaluate the relative drying performance of different building envelope systems using water trays
3. Large scale experimental investigation of the relative drying capacity of building envelope panels of various configurations  

1. A limit state design (LSD) approach for comparing relative drying performance of wood-frame envelope systems with full-scale lab, A roadmap towards intelligent net zero- and positive-energy buildings,
2. A new test method to determine the relative drying capacity of building envelope panels of various configurations
3. A new testing method to evaluate the relative drying performance of different building envelope systems using water trays
4. Building Physics: 3rd International Conference in Building Physics
5. Building pressurisation can affect possibility of mould growth
6. Comparaison de m¨¦thodes de mesure de flux de chaleur pour sp¨¦cimens de grandes et moyennes dimensions
7. Design and construction of an environmental chamber facility
8. Development of experimental procedure to evaluate potential movement of mold spores from wall cavity to indoor environment
9. Development of HAM tool for building envelope analysis
10. Effect of capillarity on rainwater penetration in the building envelope
11. Environmental chamber for investigation of building envelope performance
12. Evaluation of radiance's genBSDF capability to assess solar bidirectional properties of complex fenestration systems
13. Experimental evaluation of potential transport of mold spores from moldy studs in full-size wall assemblies
14. Experimental study of temperature distributions across two curtain wall systems
15. Identification and transport investigation of microbial volatile organic compounds in full-scale stud cavities
16. In-cavity evaporation allowance--A drying capacity indicator for wood-frame wall system
17. Interzonal air and moisture transport through large horizontal openings in a full-scale two-story test hut: Part 1 - Experimental study
18. Interzonal air and moisture transport through large horizontal openings in a full-scale two-story test-hut: Part 2- CFD study
19. Measuring air leakage characteristics with flexible double air chambers
20. Measuring air leakage of full-scale curtain wall sections using a non-rigid air-chamber method
21. Numerical investigation of the influence of room factors on HAM transport in a full-scale experimental room
22. Review and framework for large-scale laboratory studies on wetting and drying of building envelopes
23. Statistical analysis of microbial volatile organic compounds in an experimental project: identification and transport analysis
24. Study of the reduced impact of thermal bridges in two sprayed-applied polyurethane wall assemblies
25. Transfer of heat, moisture and air through metal curtain walls
26. Use of an environmental chamber to investigate large-scale envelope specimen hygrothermal performance