http://www.heatshieldradiantbarrier.com/physics_of_foil.htmread the radiation part..
My opinion is insulation lang not reflecting heat. Ang alam kung design nyan ay mabawasan yung grabeng heat not totally eliminate it. Kung gusto pa mabawasan second layer siguro. Pero also kapag insulated ka na totally medyo iinit din yan.
impakta ka talaga. meron pa yan ibang dahilan. Foil also acts as a support sa foam(sa kisame). Also yung iba ginagawa na ngang reflector ng ilaw. Madali linisin lalo na kung pupunasan mo. Kesa yung foam ang nakalabas.
sis gamit ka na lang nung insulation foam na doube sided...