Glasswool Insulation – Common Questions, Answered!

Glasswool is one of the most popular choices of insulation in Australia due to its excellent heat-trapping capabilities. The batts are placed in wall cavities for thermal insulation, with R-values ranging from 1.2 to as high as 7. This makes the various types of glasswool batts a versatile material for climate zones all around Australia.

What is glasswool used for?

Glasswool is used for a variety of building types, from residential to commercial buildings. It is usually installed in between the respective building’s structural frames; steel or timber beams, etc. The most common application is within walls, filling the hollow space between plasterboards. However, it is also suitable for roof insulation as well.

How is glass wool made?

Despite appearances, glasswool is made from a combination of recycled glass, sand, and limestone. These materials are melted in an incredibly high-temperature furnace up to 1450 degrees Celsius, before being funnelled into a cylindrical container with miniscule holes. The container rotates rapidly in a process called ‘spinning the fibres.’ During this process, fibres are forced out of the holes as long, thin strands and cool on contact with the cold external air. From here, the fibres are collected and integrated with each other to create the insulation batts we are familiar with. Sometimes, a binding agent is used to help the fibres stick together. The structure of the overlayed fibres creates million of tiny air pockets which help trap the air and reduce heat conduction, giving glasswool its respective insulation properties.

What is the difference between fiberglass and glass wool?

Some people refer to glasswool batts as ‘fiberglass batts.’ Fiberglass is manufactured in the same way as glasswool: utilising recycled glass and sand materials, spinning and heating them to create fibres. However, many forms of fibreglass are mixed with other materials such as resins and polyester to enhance the material’s strength and toughness, whilst reducing flexibility. Therefore, glasswool refers to a specific form of fiberglass that hasn’t had the additional materials to make the product hard – whilst retaining the soft, wool-like structural capabilities.

What is the difference between glasswool and rockwool?

Both glass and rockwool are wall and roof insulation batt materials. The difference is the material makeup and properties of the two. As mentioned, glasswool is made from a combination of recycled glass and sand. Meanwhile, rockwool is made of melted, fibrous volcanic rock. This gives rockwool greater density and a resistance to higher temperatures. However, glass wool is more cost-effective and versatile in its applications. Speak to an insulation expert or builder to discuss which material will be the most appropriate for your home and budget.

Can glasswool get wet?

The millions of air pockets used to trap air can also fill with water and compress the insulation. This makes it less effective at trapping heat, even after drying out. Simultaneously, water in between the insulation fibres can, unfortunately, lead to mould growth and leakage onto drywalls and plasterboard. Excessive mould spores in a home can be a safety hazard. Therefore, if your home or roof is damaged after a wet weather event or tree-falling, you should get in contact with your insurance provider and an insulation installer to assess if anything requires replacing.

Can glasswool catch fire?

Bradford glasswool is classified as non-combustible. However, ‘the plastic wrapping… binder and some facings may decompose, smoulder or burn… when heated above 300*C.’ The material makeup of the product – glass, has an incredibly high melting point, making the product very heat resistant. If a temperature is reached where elements within the insulation begin to melt, stand clear of any burning materials as they can release hazardous gases.

Is glasswool good for soundproofing?

All glasswool insulation will provide some sound-proofing capabilities. However, the most effective way to reduce sound within your building is to utilise dedicated soundscreen insulation for rooms that separate noisy from quiet areas. A sound screen can reduce the volume of noises by ~6dB or 75% in comparison to an uninsulated wall.

Are you spending too much money heating and cooling your home due to poor insulation? Are you building a home and want to improve your energy rating? Do you want to increase the value of your property? Quality insulation can solve all those issues. Find out what our team of expert installers at insulation essentials can do to provide high-quality glasswool batts for your home. Visit our online store to view our wide range of products and liaise with one of our insulation experts so you can pick what is right for you and your home today!

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