Moisture Risk in Unvented Attics Due to Air Leakage Paths
- IBACOS, Inc., Pittsburgh, PA (United States)
IBACOS completed an initial analysis of moisture damage potential in an unvented attic insulated with closed-cell spray polyurethane foam. To complete this analysis, the research team collected field data, used computational fluid dynamics to quantify the airflow rates through individual airflow (crack) paths, simulated hourly flow rates through the leakage paths with CONTAM software, correlated the CONTAM flow rates with indoor humidity ratios from Building Energy Optimization software, and used Wärme und Feuchte instationär Pro two-dimensional modeling to determine the moisture content of the building materials surrounding the cracks. Given the number of simplifying assumptions and numerical models associated with this analysis, the results indicate that localized damage due to high moisture content of the roof sheathing is possible under very low airflow rates. Reducing the number of assumptions and approximations through field studies and laboratory experiments would be valuable to understand the real-world moisture damage potential in unvented attics.
- Research Organization:
- IBACOS, Inc., Pittsburgh, PA (United States)
- Sponsoring Organization:
- USDOE Office of Energy Efficiency and Renewable Energy (EERE), Energy Efficiency Office. Building Technologies Office
- DOE Contract Number:
- AC36-08GO28308
- OSTI ID:
- 1220378
- Report Number(s):
- DOE/GO-102014-4526; 6976
- Country of Publication:
- United States
- Language:
- English
Similar Records
Moisture Risk in Unvented Attics Due to Air Leakage Paths - Minneapolis Minnesota
A Hygrothermal Risk Analysis Applied to Residential Unvented Attics
Related Subjects
Residential Buildings
IBACOS
Building America
cathedralized attics
unvented attics
hygrothermal analysis
moisture risk
closed-cell spray foam insulation
attic ventilation
attic airflow paths (cracks)
attic air leakage
moisture in unvented attics
water vapor flow rate
condensation
humidity
CONTAM
WUFI
BEopt
CFD analysis
cold climate