Glasswool insulation
Glasswool is a type of insulation material that is made from recycled glass. It is commonly used in buildings to insulate walls, ceilings and roofs to keep the interior of the building warm in the winter and cool in the summer. Glasswool is also used in a variety of other applications, such as soundproofing and as a filter material. Because it is made from recycled glass, glasswool can be considered a sustainable material.
It is similar in some respects to rockwool, but glasswool is made from recycled glass, whereas rockwool is made from basalt, a type of volcanic rock.
Glasswool is made by melting recycled glass and spinning it into fine fibres which are then formed into insulation batts or rolls. The melted glass is mixed with other materials, such as boron or alumina, to give the glasswool its insulation properties. The process of making glasswool is similar to the process used to make other types of fiberglass insulation.
There are many different types of insulation materials available, each with its own unique properties and characteristics. Comparing glasswool to other types of insulation can be difficult because it depends on the specific application and the performance criteria that are important in that situation. In general, glasswool is a sustainable insulation option that can provide good thermal insulation and soundproofing properties. It is also relatively easy to instal and can be used in a variety of different applications. However, it is not as effective as some other types of insulation at preventing the passage of moisture, so it may not be the best choice in damp or humid environments.
Glasswool can also be irritating to the skin and respiratory system. It is important to use protective gear, such as gloves, masks, and goggles when handling glasswool to avoid irritation. Additionally, glasswool products can be flammable, so it is important to follow the manufacturer's instructions when installing it to ensure that it is used safely. Glasswool itself is non-flammable, but the wrapping, resin binder, and some facings may burn.
[edit] Related articles on Designing Buildings
- Aerogel insulation for buildings.
- Acoustic insulation.
- Cavity wall insulation.
- External wall insulation.
- Floor insulation.
- Glass wool v reflective foil insulation.
- Insulating concrete form.
- Insulation envelope.
- Insulation for ground floors.
- Phenolic foam insulation.
- Reducing thermal bridging at junctions when designing and installing solid wall insulation FB 61.
- Roof insulation.
- Solid wall insulation.
- Solid Wall Insulation: Unlocking demand and driving up standards.
- Specifying insulation for inverted roofs.
- Ten facts about Expanded Polystyrene (EPS) insulation to help specifiers.
- Thermal insulation for buildings.
- Transparent insulation.
- Types of insulation.
Featured articles and news
IHBC planning for growth with corporate plan development
Grow with the Institute by volunteering and CP25 consultation.
Connecting ambition and action for designers and specifiers.
Electrical skills gap deepens as apprenticeship starts fall despite surging demand says ECA.
Built environment bodies deepen joint action on EDI
B.E.Inclusive initiative agree next phase of joint equity, diversity and inclusion (EDI) action plan.
Recognising culture as key to sustainable economic growth
Creative UK Provocation paper: Culture as Growth Infrastructure.
Futurebuild and UK Construction Week London Unite
Creating the UK’s Built Environment Super Event and over 25 other key partnerships.
Welsh and Scottish 2026 elections
Manifestos for the built environment for upcoming same May day elections.
Advancing BIM education with a competency framework
“We don’t need people who can just draw in 3D. We need people who can think in data.”
Guidance notes to prepare for April ERA changes
From the Electrical Contractors' Association Employee Relations team.
Significant changes to be seen from the new ERA in 2026 and 2027, starting on 6 April 2026.
First aid in the modern workplace with St John Ambulance.
Ireland's National Residential Retrofit Plan
Staged initiatives introduced step by step.
Solar panels, pitched roofs and risk of fire spread
60% increase in solar panel fires prompts tests and installation warnings.
Modernising heat networks with Heat interface unit
Why HIUs hold the key to efficiency upgrades.
Reflecting on the work of the CIOB Academy
Looking back on 2025 and where it's going next.




















