A Hygrothermal Risk Analysis Applied to Residential Unvented Attics

Conference · Tue Jan 01 04:00:00 EST 2013

OSTI ID:1110964

Pallin, Simon B ^[1]; Kehrer, Manfred ^[1]

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1. ORNL

Aresidential building, constructed with an unvented attic, is acommonroof assembly in the United States.The expected hygrothermal performance and service life of the roof are difficult to estimate due to a number of varying parameters.Typical parameters expected to vary are the climate, direction, and slope of the roof as well as the radiation properties of the surface material. Furthermore, influential parameters are indoor moisture excess, air leakages through the attic floor, and leakages from air-handling unit and ventilation ducts. In addition, the type of building materials such as the insulation material and closed or open cell spray polyurethane foam will influence the future performance of the roof. A development of a simulation model of the roof assembly will enable a risk and sensitivity analysis, in which the most important varying parameters on the hygrothermal performance can be determined. The model is designed to perform probabilistic simulations using mathematical and hygrothermal calculation tools. The varying input parameters can be chosen from existing measurements, simulations, or standards. An analysis is applied to determine the risk of consequences, such as mold growth, rot, or energy demand of the HVAC unit. Furthermore, the future performance of the roof can be simulated in different climates to facilitate the design of an efficient and reliable roof construction with the most suitable technical solution and to determine the most appropriate building materials for a given climate

• Research Organization: Oak Ridge National Laboratory (ORNL)
• Sponsoring Organization: EE USDOE - Office of Energy Efficiency and Renewable Energy (EE)
• DOE Contract Number: AC05-00OR22725
• OSTI ID: 1110964
• Country of Publication: United States
• Language: English