Fiberglass Insulating Fabrics
This fiber is an artificial material, used since 1713 to make fiberglass insulating fabrics. The base of this material is inorganic and has many applications, in construction, aeronautics, the manufacture of insulating fabrics (electrical, acoustic and thermal) and as a reinforcement material for the manufacture of plastics.
Artificial mineral fiberglass is classified into different types according to its structure:
- with continuous glass filament
- with mineral wools (glass wool, slag wool and rock wool)
- with refractory ceramic fibers (RCF)

The use of fiberglass in insulating fabrics arose to replace asbestos. Historically, this material has always been compared to carbon fiber, since it has similar behaviors, being cheaper and less fragile, but not as rigid.
By chemical composition, the fiber used in the manufacture of fiberglass insulating fabrics is “Type E“.
This type of fiber is the most widely used because it has very good dielectric properties and absorbs little moisture, apart from being low cost.
It represents 90% of the reinforcement used in composites and is made up of inorganic fiber composed of 53-54% SiO2, 14-15.5% Al2O3, 20 -24% CaO, MgO and 6.5-9% B2O3, with little alkali content.
Properties of Fiberglass Insulating Fabrics
Fiberglass insulating fabrics have two fundamental properties:
- Thermal: it is a very good thermal insulator due to its high proportion of surface area over weight (although it has the inconvenience of chemical attack due to this detail); because of the air that it traps inside, it makes it have good thermal conductivity (it makes heat dissipate as quickly as possible).
- Mechanics: this is a quality that is checked on the fibers that have just been manufactured, since they are the ones that should be stronger because they are ductile. An important factor to take into account is humidity, since if the surface is scratched it absorbs it, worsening the cracks and the toughness of the material.
- Other properties:
- Good electrical insulator: its vitreous structure does not conduct electricity, making it ideal for many installations.
- Low density: it has a light weight.
- Chemical resistance: fiberglass will not deteriorate or rot because it is resistant to most acids.
- Inexpensive.
- Low maintenance: due to its intrinsic characteristics, no special maintenance is required, so it is profitable in terms of cost/time.
- Versatility: thanks to the different types that exist, there is a wide range of compounds in the labor market.
- Permeable to electromagnetic waves.
- Fiberglass is incombustible by nature (it does not spread the flame or cause smoke or toxicity with heat).
- Dimensional stability: it is not very sensitive to variations in temperature and hygrometry, it has a low coefficient of expansion.
- It is compatible with organic materials, which gives it the possibility of being associated with numerous synthetic resins, as well as with certain mineral matrices, such as plaster or cement.
- Great flexibility.
Applications of Fiberglass Insulating Fabrics
The most common fiberglass insulating fabrics:
- Textile Industry
- Covering fabrics for electrical material, chemical filters and decorative fabrics, the objective being that the fibers are incombustible and that they do not stretch.
- Reinforcement of tapes, plastic, and paper.
- Components for vehicles.
- Manufacture of sports equipment: poles and skis and the most important, as part of fiberglass reinforced plastics (GRP).
- Manufacture of special molded plastics (ground fiberglass format).
- Uses in construction (fiber wool format), fabrics and electrical, acoustic and thermal insulation).
Products in Fiberglass Insulating Fabrics
- We have a wide catalog of products classified as fiberglass insulating fabrics, for all market needs, recommended for uses up to 500ºC, from cords to braids (loose and knitted), fabric tapes, insulating weather stripping, fire blankets and screens, insulating mats, etc.
- For other more demanding uses, from between 500ºC and 750ºC we recommend the use of these products but with fiberglass with vermiculite.
