RTRA
roof thermal research apparatus
The Roof Thermal Research Apparatus (RTRA) was constructed for documenting the effects
of long-term exposure of small, low-slope roof test sections to the East Tennessee climate.
The RTRA has four 4 ft by 8 ft openings in its roof to receive different instrumented low-slope
roof test sections. Each test section comprises one to eight configurations. Its original
use showed the in-service aging effects with CFC and alternative blowing agents for
polyisocyanurate foam boards in roofs covered by black and white membranes. These test
sections are shown in the photographs below. More recent use of the RTRA has been to document
the thermal performance of low-slope roofs coated with reflective coatings. In June 2000, we
completed a three-year study with the support of the Roof Coatings Manufacturers Association.
The thermal performance of 24 different roof coating systems was monitored simultaneously. The
first set of photographs in the article at http://www.ornl.gov/roofs+walls/research/reflective.htm
shows how these test sections were constructed. Wall panels and slab-foundation edges of the RTRA
building can also be instrumented to monitor their thermal performance. The interior of the RTRA
is heated and cooled to constant conditions year round. The RTRA contains a system that does
automatic, continuous data acquisition and houses communications equipment that connects the
data system to the Oak Ridge National Laboratory's intranet.
This page updated on April 26, 2001 by Diane McKnight.