WRONG!!
NOTHING can stop heat loss! If you have ever estimated what percentage of heat from your house goes to the
outside the answer is 100% - all of it! Insulation SLOWS DOWN the rate at which heat is lost from something warm - thus the more insulation a house has,
the cheaper it is to run. The more insulation YOU have (when it is cold) the longer you feel warm.
So never say "insulation stops heat loss" and never say "insulation traps heat".
With most insulation it is the air that is trapped within the fibres or material which insulates, because air is an excellent insulator (or to think
more properly: it is a very poor conductor of heat)