So it is with electrical conductors, some being better than others. … Glass, for instance, is a very good insulator at room temperature, but becomes a conductor when heated to a very high temperature. Gases such as air, normally insulating materials, also become conductive if heated to very high temperatures.

Is glass a conductor yes or no?

Glass is a very poor heat conductor. It has one of the lowest possible heat conduction a solid (without air trapped in it) can possibly have, this is mostly due to its lack of ordered crystal structure. Since it’s an insulator, the electronic contribution to the thermal conductivity is very small.

Is glass an insulator?

Perhaps the best known material that has excellent insulating properties is glass. In addition to being a good electrical insulator, glass has many other useful properties. It is a good thermal insulator (most material are either both or neither), and it is resistant to many corrosive chemicals.

Glass isn’t as good a conductor of heat as metal, but it’s great insulator, making it retain heat well. Because of this glass performs a lot like dark metal — foods absorb more heat and bake faster, making glass a good choice for pies and some breads.