The use of continuous exterior insulation over structural framing is an easy way to improve the effective R-value of an assembly and to minimize the effects of thermal bridging. The exterior insulation product used must not be sensitive to moisture, as it will be exposed to periodic wetting. The continuity of thermal barriers should be considered while detailing, especially at interfaces between assemblies.

Heat will travel most through the path of least resistance, meaning that gaps or conductive materials used as part of the thermal barrier will result in greatly reduced effective R-values. Conductive materials like metal that penetrate the thermal barrier lead to heat loss and potential durability issues. These thermal bridges should be avoided and/or reduced to a minimum.