What is the minimum R-value for insulation beneath radiant piping in slab-on-grade applications?

The minimum R-value for insulation beneath radiant piping in slab-on-grade applications is set to ensure energy efficiency and proper function of radiant heating systems. An R-value of 5 provides an effective level of insulation, reducing heat loss from the radiant heating system into the ground and ensuring that the heat generated is directed upward into the living space. This level of insulation helps maintain the efficiency of the system, contributes to energy savings, and provides comfort for occupants by maximizing the effectiveness of the radiant heat.

This requirement aligns with energy code standards, which are designed to promote the efficient use of energy in buildings. In slab-on-grade designs, proper insulation beneath heated elements is critical to the overall performance of the heating system, as it not only conserves energy but also aids in preventing potential moisture issues associated with uninsulated slabs. Therefore, an R-value of 5 is established as the minimum necessary for these applications.