Cold Climate Window Insulation Evaluation

 Windows are a major source of heat loss in a building envelope and a potential source for mold and rot if unmitigated condensation occurs. Because upgrading to high-performance triple-pane windows is expensive, homeowners have found other methods to reduce heat loss through their windows. Some of these techniques, however, can excerbate condensation issues.

This study builds upon CCHRC's existing research on moveable window insulation. In 2011, we compared nine different window treatments in terms of thermal effectiveness, affordability, ease of installation, durability, functionality, and condensation resistance (found here). This new window treatment consists of adding a 4” tall layer of Expanded Polystyrene (EPS) foam board pressure fit into the exterior frame of the window against the outside of the glass. This 4” EPS  covers the bottom portion of the window, where most condensation occurs while leaving the majority of the window with a clear view of outside.


Our primary question is: Is placing foam board on the exterior of the window frame an effective solution for increasing a window’s condensation performance?

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Little Ventilation Project Looking at ventilation systems that can improve indoor air quality in small homes while limiting energy use.
Slab-on-Grade Foundation Best Practices An evaluation of best practices for insulating under slab-on-grade foundations
Vacuum Insulated Panel Test CCHRC is testing how Vacuum Insulated Panels can be assembled to achieve extremely high R-values in cold climate homes.
Designs for Rural Alaska Walls Monitoring CCHRC demonstration homes for efficiency and moisture infiltration several years after construction.
Structural Insulated Panels Structural Insulated Panels (SIPs) are prefabricated building materials used in residential construction in Alaska. This project prepared resources for homeowners who want to learn about SIPs, where they are used in cold climates, and considerations for Alaska.