A concrete tile roof system’s long-term performance and energy efficiency is due in large part to roof tile’s unparalleled thermal mass that significantly reduces heat transfer into the attic space. In addition to thermal mass, concrete roof tile systems include functional air space between the back of the tile and the roof deck. The air space above the roof deck creates an insulative effect that further enhances the heat transfer resistance and combines to extend the life span of the system.
The heat transfer reduction that occurs on a concrete tile roof has been studied at length and there have been several very informative studies that have quantified the benefits of the air space under tile. The research report, The Equivalent Thermal Resistance of Tile Roofs with and without Batten Systems (Miller, Olson and Graves), looked at the data collected in several studies and showed that, depending on location and the size of the airspace, the R-value equivalency of a concrete tile roof system can be more than R-4 equivalence. Read more.