Tile’s Energy Efficiency

Roofing tiles are the only materials currently in use that possess two inherent qualities necessary for energy reduction: first, the natural thermal resistance in the raw materials themselves that are created by the larger cross-sectional areas of the tiles while installed. Secondly, since they are installed individually, rather than in sheets or in overlapping style, the natural airspace around the tiles creates a natural ventilation that provides a thermal barrier for heat transfer to the roof deck. This “Above Sheathing Ventilation” (ASV) can result in greatly reduced heat flux transfer when compared to a baseline asphalt shingle. This can assist in the movement of the peak load demands by several hours, which directly benefits those living in warm climates as well as those in cold conditions.

Westile Corona 2Given the potential for federal tax credits and state rebates, concrete and clay tile roofs will save you money every month:

  • Significantly reduces monthly energy bill
  • Get credit from your local utility for power your home produces
  • 30% Federal tax credit is available
  • Adds significant resale value to the home
  • Protect yourself from utility cost increases
  • Rest assured in your low maintenance, state-of-the-art system

As early as the 1970’s, the Florida Power and Light Company conducted extensive tests on tile roofing systems to see if there was a way to help reduce the transfer of heat into the attics of homes. The Florida Solar Energy Center (FSEC) continued testing and found that “direct deck tile systems” reduced ceiling heat flux by nearly 40 percent. As recently as the mid-1990’s, FSEC concluded that vented tile roofs reduced ceiling flux by as much as 48 percent compared to the commonly-used black shingle roof.

In recent years, the Tile Roofing Institute has worked extensively with Dr. William Miller at Oak Ridge National Laboratory to conclusively document the natural ventilation properties of tile roofs. This breakthrough research has shown that air flow beneath the tiles, otherwise known as sub-tile ventilation, combined with a pitched roof design, creates a natural – and eye-popping — cooling effect that can be quantified. Notably, his research has shown that heat transfer through the roof deck into a home’s attic space can be reduced by a full 70 percent when compared to a conventional asphalt shingle roof on the same house.

“A properly installed tile roof reduces the amount of heat transferred to a building’s attic by nearly 50 percent.” -Oak Ridge National Laboratories

Ludowici Energy Efficient TileImportant research performed by Lafarge, a world leader in concrete product research and development has centered around testing protocols for reflective roof surfaces that are curved and colored in nature, rather than static, flat decks. TRI has offered to assist in developing new standards for measuring reflectivity standards that mirror real-life, sloped tile surfaces. Also, in conjunction with the Cool Roof Rating Council, which was formed in 1998, TRI continues to perform bench mark statistical analyses for the ASTM C1549: Reflectometer Test, as well on the ASTM E1918: Pyranometer Test Methods, to provide a rating for tile roofs based on the reflective abilities they provide for both flat and curved profiles.

For those considering a new roof, or re-roofing an existing structure, tile comes to the forefront as a cost-effective, long term consideration, notably in an era of soaring energy costs, a return to more natural, less disposable raw materials, and a focus on smart, aesthetically pleasing construction that literally lasts a lifetime and beyond. Having broken through the imaginary limitations and geographic barriers that some had created for these materials, we continue to see them installed in both warm and cold climates due to their superior performance properties in energy efficiency.