The performance of an in-floor heating system depends largely on the quality of its radiant panels, with different manufacturers favoring different materials. Some continue to rely on gypsum concrete, which was a staple in earlier generations of the technology. Concrete comes with one major drawback—it's sluggish. That limitation led system makers like Warmboard to embrace aluminum instead, because the metal conducts heat 232 times better. That way, if you adjust the thermostat, Warmboard responds almost instantaneously so you don't have to postpone your comfort.