Hi @edfe66a5, I apologize if my previous response was unclear. Radiant barriers are designed to reflect radiant heat, which is the transfer of heat through electromagnetic waves. Radiators, on the other hand, produce heat through convection, which is the transfer of heat through the movement of fluids. Therefore, radiant barriers are not designed to reflect the heat produced by radiators.
Regarding your question about the heat produced by a house, radiant barriers are typically installed in the attic to reflect radiant heat from the sun, which can help keep the house cooler. The heat produced by the house itself is not typically reflected by the radiant barrier back inside, as the barrier is designed to reflect radiant heat from the outside.
I hope this helps clarify things. If you have any further questions, feel free to ask!