The greater the temperature difference, the faster the heat flows to the colder area. Using this process, heat energy is passed through a solid, liquid or gas from molecule to molecule in a material. In order for the heat to be conducted, there should be physical contact between particles and some temperature difference. Thus, Thermal conductive sealant helps in measuring the speed of heat flow passed from particle to particle. The rate of heat flow through a specific material will be influenced by the difference of temperature and by its thermal conductivity.

Best insulation materials should have the lowest thermal conductivity to reduce the total coefficient of heat transmission. Dry stagnant gas is one of the best insulating materials. The higher is the number of cells which maintain the gas stagnant, the smaller is their size and their thermal conductivity is lower of such insulating materials.

There are various common insulation materials available on the market but each of these insulations has their highs and lows. This measurement of high and low helps in deciding which insulation material you should choose. While opting for a material you should be sure to be aware of what would work the best in your situation. Polyurethane foam is effective as an insulator because it has a high proportion (90 percent minimum) of non-connected closed microcells, filled with inert gas.

Some of the rare insulation materials not mentioned in natural fibers such as hemp, sheep’s wool, cotton, and straw. Polyisocyanurate which similar to polyurethane is a closed cell thermoset plastic with a high R-value is used as an insulator as well. Some health hazardous materials used as insulation and are now outlawed, unavailable are vermiculite, perlite, and urea-formaldehyde. These materials are banned or unavailable for containing formaldehyde or asbestos.