What is a thermal bridge?

A thermal bridge is a component, or assembly of components, in a building envelope through which heat is transferred at a substantially higher rate than through the surrounding envelope area.

What is a solution to thermal bridging?

One solution, which is an improvement to the "over-the-purlin" technique, is to use insulating spacers to provide thermal isolation or a thermal break between the panels and purlins. Batt insulation remains uncompressed by installing the spacers between the purlins. R-19 insulation installed using this technique yields an effective R-value of approximately R-14 (see Figure 2).

Figure 2