Is Fiber Insulator? 7 Facts You Should Know!

Fiber is a thread-like structure made up of hydrocarbons. In this article, we shall discuss the conductivity of fiber, whether it is an insulator or conductor.

Fiber is an insulator because it does not allow the electric current to pass through, but some fiber has good thermal conductivity depending on the porosity. Fiber is a carbohydrate that is degraded into sugar and is made up of hydrocarbon bonds that requires a large amount of energy to break these bonds.

There are different types of fibers. We shall further discuss the insulating property of the fiber and the different uses of fiber as an insulator. We shall also discuss the electrical conductivity of fiberglass, fabric, and carbon fiber. We shall also list the disadvantages of fiberglass insulation.

Why is fiber a good electric insulator?

The electric insulators do not allow the electric current to pass through the matter. Let us understand why fiber is a good electric insulator.

The fiber is a good electric insulator because there are no free electrons to conduct electric current. The bonds between the carbon and hydrogen atoms constituting the fiber are very strong, require more energy to break them apart, and set electrons free for conduction.

Is fiber a thermal insulator?

Thermal insulators do not allow heat energy to pass through the matter through the convection process. Let us see whether fiber is a thermal insulator or not.

Fiber can be a thermal insulator as well as a conductor depending upon the type of fiber. Most fibers are thermal insulators that do not allow heat to pass through them, for example, synthetic plastic, wool, wood, cellulose, polystyrene, etc. While ceramic fibers and glass fibers show small thermal conductivity.

Uses of Fiber as an Insulator

Due to the insulation property of fiber, it is used as an insulator in different industries and for various purposes. Let us list some of the uses of fiber as an insulator.

  • Ceramic fiber boards are used to get rid of heat.
  • Fiber papers are used as insulation seals and gaskets.
  • Fiber ropes and cables are used in industries.
  • Fiber textile is used for clothing to avoid the catch of fire.
  • Fiber is used in the concrete and false ceiling to reflect the heat rays.

Is fiberglass insulator?

Fiberglass composes of fine fibers of glass used in manufacturing industries. Let us discuss whether fiberglass is an insulator.

Fiberglass is a poor insulator as a few heat fluxes can pass through it. The fibers are packed very closely in fiberglass, and there is less space for voids that hinder the electric and heat flux from passing through the fiberglass. But, fiberglass is a good conductor of heat and has high thermal conductivity.

Can fabric be an insulator?

Different types of fabrics include woven, wool, cotton, chiffon, leather, silk, satin, velvet, etc. Let us discuss whether a fabric is an insulator or not.

Fabric can be an insulator as the resistivity of fabric to resist the heat flow is less and sustain to a specific temperature. Some fabrics are insulators, while some are not. A good insulating fabric will reduce heat loss. The insulation capacity of fabric is based on the rigidity and toughness of the fabric.

Is carbon fiber an insulator or conductor?

Carbon fiber is a polymer, also called graphite fiber, as it is made up of carbon matter. Let us discuss whether carbon fiber is an insulator or a conductor.

Carbon fiber can conduct electricity but is not a good electric conductor like other metals. The atomic structure of carbon fiber is similar to that of graphite. The conductivity is due to the electrons drifting through the covalent bonds. The heat flux can easily pass through it and shows high thermal conductivity.

Image Credit: Plant fiber by Uwe Besendörfer (CC BY-SA 3.0)

Disadvantages of Fiberglass Insulation

Fiberglass insulation is done in houses and buildings to maintain the room temperature and for safety. Let us list some disadvantages of the same.

  • Heat energy escapes due to the air exchange through the fiberglass.
  • The density of fiberglass is less, and hence there is air leakage.
  • There are chances of cleavages and breakage of fiberglass.
  • Fiberglass loses the insulation property when it is wet.
  • There is moisture contamination during fog in a living space.


We can conclude with this article that the fiber can be an insulator or conductor depending upon the type of fiber. Most of the fibers are insulators due to the strong bonds of the atoms that do not break and allow the flow of heat and electricity through the matter.

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