HYDRONIC PANELS
By Bob “Hot Rod” Rohr
Looking up your
radiant options I
would challenge you to find a more comfortable heating emitter than a radiant panel – assuming, of course, that the system was properly designed, installed and dialed in. And while visions of cast iron radiators may come to mind when thinking about residential hydronics, when it comes to radiant, today’s systems offer a wide array of heat emitter options for buildings of all kinds. With the introduction of flexible plastic tubing to North America in the late 1980s, it did not take long for creative designers, plumbers and heating aficionados to come up with new ideas for radiant panels. Radiant floors were no-brainers. Concrete slabs lend themselves nicely to radiant heat transfer. The large surface area becomes a radiator by circulating a warm fluid, generally water, through a network of tubing encased in the concrete pour, but not every home or building involves a concrete slab. So, then what? Gypsum-based floor coverings had been developed for fire and sound protection in commercial buildings like hotels, and this gave the radiant artists another palate. Installing tube in a 1-1/2” overpour on a framed floor is considered a medium-mass installation, and will react more quickly to change than high-mass slabs. Numerous methods have been developed to put tubing below wood subfloors, or in a buildup on top of the subflooring – what we call “dry” systems. These applications, being even lower mass, can be ramped up or down much more quickly compared to the higher mass systems. This application works nicely in climates that see frequent and wide temperature swings throughout the heating season. My home in Missouri is a classic example of wide winter time temperature swings. In some cases, it is not possible or affordable to install retrofit radiant floors, but fear not, radiant aficionados have a solution for that, too. Knowing that heat travels in any direction, from a radiant panel to a surface it sees, some have started to look up, and build radiant ceilings. Options include tubing or even
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electric heat cable, and anyone who has stood below a radiant ceiling has experienced warmth that seems to simply wash over you. Radiant ceilings provide a nice, unencumbered area to build the radiant panel, too, without restrictive coverings or furniture to be concerned with or designed around. Higher BTU/square foot output is also possible. We can run surface temperatures a bit higher, since no bare feet are contacting the ceiling – at least not in most cases. There is yet one more surface that we can easily turn into a radiant panel. What about the walls that surround us?
