Don’t believe all you read!! Find other references…
From a LARGE company’s website:
“Nearly 2/3 of the heat lost or gained through the building envelope is through radiant heat flow.”
Yes come and buy our great foil covered product and save some, well maybe a teeny-eeny bit of energy!!
PS: Forgot to give the website:
From the “Residential Energy Audit Manual” by the Dept of Energy with help from the Oak Ridge National Laboratory, The U. of Mass Energy Education Center, and the Solar Energy Research Institute:
“Although all three mechanisms of heat transfer (conduction, convection, radiation) occur within and through the envelope of a home, in most cases, the effects of radiation occur primarily at the outside surfaces of the outside walls. Heat radiated from these surfaces must first have been conducted out through the walls of the home. This means that heat losses or gains from radiation can be ignored since the initial conductive losses or gains will have been carefully calculated.”
Since this loss is at the outside WRB/siding surface and will be extremely low due good insulation levels in walls, there is little more energy that can be saved economically with the higer priced outer thin insulation/ permeable foil layer. Remember that the “Law of Diminishing Returns” is working very badly against you and the builder at this point.