Here's one of the top products run in PME throughout the year 2002. RTI Pex Piping Systems has introduced ThermalBOARD Modular Radiant Heating Panels for use with their 3/8" Heat-PEX tubing. ThermalBOARD is a thermally coated composite wood product, factory grooved to accommodate PEX tubing. The bonded aluminum laminate surface provides excellent heat transfer and system performance. Each lightweight panel is 5/8" thick, measuring 16" x 48". ThermalBOARD's modular design allows for fast, easy and cost-effective installation over a variety of subfloor materials, walls and ceilings. RTI Pex Piping Systems.