Radiant heat systems typically last between 15 and 20 years. The longevity of a radiant heat system depends on the quality of the system, the type of fuel used, and the amount of maintenance it receives. High-quality systems with regular maintenance can last up to 25 years. Additionally, the type of fuel used can also affect the lifespan of a radiant heat system. Natural gas systems tend to last longer than electric systems, as they are more efficient and require less maintenance.