Secondary Author(s)

Sherwin, John

Report Number




Roofs; Buildings; Humidity; Moisture; Cooling; Ventilation; Attics


Florida Solar Energy Center (FSEC) has measured summer attic thermal performance of six roofs at a heavily instrumented test site, the Flexible Roof Facility (FRF). The FRF is a 1,152 square foot (107 m2) building with six roof adjacent test cells which are heavily insulated from each other. Some 233 channels of data were obtained; this includes twenty temperature measurements per cell, extensive meteorological conditions, surface and tower wind speeds and attic humidity and roof surface moisture accumulation. The data were collected over the ASHRAE definition of summer (June - September) to compare cooling season thermal of roofing systems. Six differing roof types were evaluated with variations in color, ventilation, roof mass and the use of radiant barrier systems (RBS). The tests show that roof system reflectivity greatly influences attic summer temperatures. Two white roofing systems outperformed the other options. Another large improvement comes from greater roof mass; tiled roofs performed better than those with asphalt shingled roofs. An increased attic ventilation rate improved the effectiveness of an attic radiant barrier. Of the evaluated options white tile roof best controlled attic heat gain.

Date Published



Original Publication: Parker, D., Sherwin, J., "Comparative Summer Attic Thermal Performance of Six Roof Constructions," The 1998 ASHRAE Annual Meeting, Toronto, Canada, June 20-24, 1998

Local Subjects

Buildings - Attics; Buildings - Cooling; Humidity; Buildings - Moisture; Buildings - Roofs; Buildings - Ventilation


FSEC Energy Research Center® Collection



Rights Statement

In Copyright