Impacts of Air Cavities on Hygrothermal Performance of Retrofitted Timber Frame Assemblies in Six US Climates
Publication: Computing in Civil Engineering 2023
ABSTRACT
Despite the growing interest in moisture behavior in buildings, building envelope designs rarely undergo assessment for hygrothermal control, especially when it comes to energy efficiency retrofits. Timber frame structures often incorporate a continuous air cavity that separates the exterior cladding from the wall sheathing. Indeed, using an air cavity increases thermal performance. To date, however, few studies have examined the impacts of air cavities on the hygrothermal performance in retrofitting projects. This study used WUFI Pro software to assess the influence of air cavities on the hygrothermal performance of existing building envelope components. We tested various ventilation rates for each wall assembly across six climates of the US. Findings show that adding an air cavity on the exterior side of the wall can reduce water accumulation during the simulation period. This element can prove especially beneficial in hot and humid climates since it increases dryness rates in the assembly.
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Information & Authors
Information
Published In
Computing in Civil Engineering 2023
Pages: 831 - 840
History
Published online: Jan 25, 2024
ASCE Technical Topics:
- Building design
- Building materials
- Cavitation
- Climates
- Construction engineering
- Construction methods
- Design (by type)
- Engineering fundamentals
- Engineering materials (by type)
- Environmental engineering
- Fluid dynamics
- Fluid mechanics
- Frames
- Hydrologic engineering
- Materials engineering
- Rehabilitation
- Structural engineering
- Structural members
- Structural systems
- Structures (by type)
- Walls
- Water and water resources
- Wood and wood products
- Wood structures
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