A problem with new buildings known as "thermal bridging" needs to be considered if you hope to maximize the energy-efficiency of a roof system, says Scott Armstrong, manager of building science and sustainability at MMM Group in Canada. "If we only fasten the bottom layer of insulation and we adhere the top layer and finishing membrane and surfacing, we only have about a 3% loss in our thermal performance of the insulation," Armstrong says.

Related Summaries