This test shows what is currently the most popular style of radiant heating in the US - Concrete. It is an old technology that has seen very little change over the last hundred years. Like other tests, Warmboard reaches a surface temperature of 70º F in 19 minutes. The Gypsum Concrete took just over an hour – a long time to wait if you’re cold in the morning.
The striping (the temperature variation across the surface of a panel) only varies by 2.4º F on Warmboard while the Gypsum Concrete is at 3.2º. Warmboard generated 18 BTUs/HR/SF (British Thermal Units per hour per square foot), while the Gypsum Concrete produced 16. This means Warmboard is using the energy you pay for more effectively.
Tubing on the Warmboard panel is 12" apart and is 6" apart in the Gypsum Concrete.
Both panels were in an environment with a 65º F air temperature. They both also had the same water temperature, 120º F. The insulation over each panel had a R-Value of 2.22.
Note: Temperatures were taken from just above the center of each panel. Striping differences were also gathered from this area. Temperatures from on top of the tube were compared to temperatures at the midpoint between the tubing pattern.