Quilted Underfloor Segments

Underfloor RollThe Earthwool® glasswool: Quilted underfloor segments are a new generation of softer, safer and more environmentally friendly glasswool insulation. The segments are manufactured from durable silicone coated glasswool and are completely wrapped in a breathable plastic film, providing a wind wash barrier and a product that is easy to install.

Advanced compression packaging reduces handling time and the storage space required on-site. Knauf Insulation offers Earthwool glasswool in a wide range of sizes and R-values.

Earthwool glasswool can be used for cavity walls, floors, ceilings, attics, basements and crawlspaces. It is highly resilient, recovering quickly to full thickness. It also greatly reduces the transmission of noise in the home.

If you're installing Earthwool glasswool yourself then don't forget to check out our DIY Safety Instructions and Precautions before you start.


Earthwool glasswool Quilted underfloor segments provide a cost-effective thermal and acoustic barrier for energy-efficient underfloor applications. The consistent quality, low dust, and clean-cutting resilient glasswool make fabrication easy and installation fast. The product is ideally suited to timber framed construction and a wide range of joist spacing’s up to 515mm centres.

Earthwool glasswool Quilted Underfloor comes in long 2.7m segments and are suitable for most sub-floor applications including pole houses and open sub-floors. It is designed for use above “non-occupied” spaces such as the following:

When installed above “occupied spaces”, such as workshops, garages, and basements, a suitable compliant lining such as plasterboard or fibre cement should be installed over the insulation. Alternatively, we recommend installing Earthwool glasswool Underfloor roll with Wind Wash Barrier. Product codes 546235 (500mm) and 492704 (600mm).

Proven Performance

    • Preferred by professional installers concerned with quality, appearance and productivity.
    • Excellent thermal performance - the wind wash barrier ensures the thermal performance is not affected by air movement under the floor.
    • Excellent acoustical properties reduce sound transmission.

        Wind Wash diagram


          • Earthwool glasswool is odourless, rot proof, non-hygroscopic, do not sustain vermin and will not encourage the growth of fungi, mould or bacteria.
          • 15 year warranty.

        Superior Handling

        • Highly resilient recovers quickly to full thickness for a snug fit and superior finished aesthetics.
        • Consistent quality materials feel good, cut easily and install fast. 
        • Low dust for easier handling and increased productivity.

        Convenient Packaging, Easier Handling

        • Earthwool glasswool is packaged in a strong, white poly bag that offers excellent protection from abuse, dust and moisture.
        • Earthwool glasswool packages feature easy to follow installation instructions.
        • Master bag units (containing multiple packs) ensure reduced handling costs with improved compression – more square metres per bag, more square metres per truck load, fewer trips to the job site and less warehouse space for storage.

        Superior Service and Support

        • Knauf Insulation is totally focused on providing first class customer service, producing high quality product and ‘on time in full’ deliveries. 
        • Knauf Insulation recognises the need to establish, develop and support a professional network of distributors and re-sellers in order to service a growing insulation market. 
        • Knauf Insulation is committed to providing a comprehensive range of relevant literature and web-based technical information to support specifiers and consumers.

        Quilted Underfloor Segments

        Material Code R-Value (m²K/W) Thickness (mm) Width (mm) Length (mm) Area per pack (m²)
        596252 1.5 70 470* 2700 19.04

        *glasswool is 470mm wide plus tabs for stapling.

        Calculate how many packs of insulation you will need here.


        Specification Compliance

        AS/NZS 4859.1: 2002 Materials used in the Thermal Insulation of Buildings and comply with the New Zealand Building Code requirements: B2 – Durability, E3 – External Moisture, F2 – Hazardous Building Materials, and H1 – Energy Efficiency. The Earthwool glasswool: Underfloor range is an acceptable solution in terms of the New Zealand Building Code. This product is designed for use in timber framed floors in new and existing domestic and commercial buildings. 

        Thermal Conductivity
        • ASTM C 518

        Thermal Resistance
        • ASTM C 653

        Specification Guide

        The underfloor insulation shall be Earthwool glasswool Quilted Underfloor segments with silicone coated glasswool R*, *mm thick. CFC/HCFC free, zero ODP & GWP, glasswool insulation with high post-consumer recycled glass content and with  ECOSE® Technology. It will be manufactured under Quality Assurance Standards ISO 9001:2008 and ISO 14001:2004 by Knauf Insulation and shall be installed in accordance with the instructions issued by them.

        *architect to insert details of products used


        The formulation used for Earthwool glasswool insulation has been independently assessed to meet the requirements of the stringent Note Q standard (and is therefore consistent with the highest Australian and New Zealand industry standards), and also assessed by Knauf Insulation against the criteria of the Australian Safety and Compensation Council ASCC Approved Criteria for Classifying Hazardous Substances [NOHSC: 1008 3rd Edition]. As a result of this assessment, Earthwool glasswool insulation is not classified as hazardous according to the NOHSC criteria.

        Technical Data

        Water Vapour Absorption (ASTM C 1104)
        • Less than 5% by weight.

        Corrosion Resistance (ASTM C 665)
        • No greater than sterile cotton.

        Microbial Growth (ASTM C 1338)
        • Does not support microbial growth.

        Combustibility (AS/NZ 1530.1)

        • Non-combustible.

        *data applies to Earthwool glasswool only and excludes plastic film

        Earthwool glasswool MSDS