Knauf 100mm Loft Roll 44 Combi-Cut Glass Mineral Wool Insulation 13.89m²

Knauf 100mm Loft Roll 44 Combi-Cut Glass Mineral Wool Insulation 13.89m²

Knauf 100mm Loft Roll 44 Combi-Cut is a non-combustible glass mineral wool insulation roll designed for insulating cold pitched roofs at ceiling level. Ideal for loft insulation projects, the 100mm roll provides reliable thermal performance with a declared thermal conductivity of 0.044 W/mK and a thermal resistance of 2.25m²K/W.

Each roll covers approximately 13.89m² and measures 12180x1140x100mm. The Combi-Cut design is partially perforated, allowing the 1140mm-wide roll to be split into 2 x 570mm or 3 x 380mm widths for flexible installation between ceiling joists, or used uncut as a full-width layer where required.

Key Features & Benefits - Knauf 100mm Loft Roll 44 Combi-Cut

• Manufacturer: Knauf Insulation


• Range: Loft Roll 44


• Product format: Combi-Cut insulation roll


• Material: Glass Mineral Wool


• Thickness: 100mm


• Roll dimensions: 12180x1140x100mm


• Coverage: approximately 13.89m² per roll


• Thermal conductivity: 0.044 W/mK


• Thermal resistance: 2.25m²K/W


• Reaction to fire: Euroclass A1 - non-combustible


• Combi-Cut widths: 2 x 570mm or 3 x 380mm


• Application: Cold pitched roofs at ceiling level / loft insulation


• Technology: Manufactured using ECOSE® Technology


• Manufacturer product code: 2404154


• EAN / GTIN: 5012061815696


• Partially perforated for flexible installation


• Can be fitted between suitable ceiling joists or used uncut at full width


• Suitable for new loft insulation and topping up existing insulation where specified

100mm Loft Insulation for Cold Pitched Roofs

Knauf Loft Roll 44 is specifically designed for insulating cold pitched roofs at ceiling level, making it a practical choice for domestic loft insulation projects, new-build homes, extensions and refurbishment work.

Installing insulation at ceiling level helps reduce heat transfer between the heated rooms below and the unheated loft space above when installed as part of a correctly designed roof construction.

13.89m² Coverage Per Roll

Each Knauf 100mm Loft Roll 44 provides approximately 13.89m² of insulation coverage.

The roll measures approximately 12.18m long x 1.14m wide before being separated along the Combi-Cut perforations.

When calculating how many rolls are required, allow for the actual loft dimensions, obstructions, cutting and appropriate installation wastage.

What Does Combi-Cut Mean?

Knauf Combi-Cut insulation is supplied partially perforated across the roll width, allowing installers to divide the insulation into narrower sections without unnecessarily cutting the complete roll by hand.

The 1140mm-wide roll can be separated into:

• 2 x 570mm widths


• 3 x 380mm widths

The roll can also be left uncut and installed at its full 1140mm width where appropriate.

This flexible format helps make the product suitable for fitting between different ceiling joist layouts as well as for full-width installation.

Ideal as a Base Layer Between Ceiling Joists

The 100mm thickness makes this Loft Roll 44 particularly useful as a first or base layer of loft insulation between suitable ceiling joists where 100mm insulation is required by the project specification.

Further insulation can then be installed above the joists where additional overall insulation depth is required.

The total insulation thickness required should always be determined by the individual construction, existing insulation and applicable project or Building Regulations requirements rather than assuming that one 100mm layer alone provides the required finished thermal performance.

0.044 W/mK Thermal Conductivity

Knauf Loft Roll 44 has a declared thermal conductivity of 0.044 W/mK.

At 100mm thickness, the product provides a thermal resistance of approximately 2.25m²K/W.

The final thermal performance of the completed roof or ceiling will depend on the complete construction build-up, including the total insulation depth, timber joists and other building materials.

Euroclass A1 Non-Combustible Insulation

Knauf Loft Roll 44 achieves a Euroclass A1 reaction to fire classification in accordance with EN 13501-1.

A1 is the highest reaction-to-fire classification and means the glass mineral wool insulation is classified as non-combustible.

Glass Mineral Wool with ECOSE® Technology

Knauf Loft Roll 44 is manufactured from glass mineral wool using Knauf Insulation's ECOSE® Technology.

ECOSE® Technology uses Knauf's plant-based binder technology and is incorporated across its current glass mineral wool insulation range.

Installing Between Ceiling Joists

The partially perforated Combi-Cut format allows the insulation to be divided into 570mm or 380mm sections where these widths suit the roof construction.

The insulation should be fitted closely between the joists to minimise gaps while avoiding unnecessary compression of the mineral wool.

Always confirm the actual clear distance between the joists before selecting the most appropriate Combi-Cut width.

Cross-Laying Additional Loft Insulation

Where additional insulation depth is required, a further suitable loft insulation layer can be installed above the first layer in accordance with the project specification.

Cross-laying insulation over the ceiling joists can help reduce thermal bridging through the timber and increase the overall thermal resistance of the loft insulation build-up.

For example, customers may use a suitable base layer between the joists followed by another Loft Roll thickness above, but the exact insulation build-up must be selected for the individual project.

Suitable for New Insulation & Loft Upgrades

Knauf 100mm Loft Roll 44 can be used for both new insulation installations and upgrades to existing loft insulation where its thickness and performance meet the project requirements.

Typical applications include:

• Cold loft insulation


• Pitched roofs insulated at ceiling level


• Insulation between ceiling joists


• Base layers beneath additional loft insulation


• Cross-laid loft insulation where suitable


• Topping up existing loft insulation


• New-build homes


• House extensions


• Renovation and refurbishment projects

Loft Ventilation & Installation Considerations

Care should be taken during installation to avoid blocking required roof ventilation openings at the eaves or elsewhere within the roof construction.

Electrical cables, recessed lighting, water tanks, pipework and other services within the loft should also be considered before installing insulation and treated in accordance with the appropriate manufacturer's or project requirements.

Always follow Knauf Insulation's current installation guidance and the specification for the individual roof construction.

Handling Glass Mineral Wool Insulation

Suitable protective clothing and personal protective equipment should be worn when handling and cutting mineral wool insulation. Gloves, eye protection and respiratory protection should be used where required.

A suitable insulation knife or sharp utility knife and straight edge can be used where additional cutting is necessary.

Why Choose Knauf 100mm Loft Roll 44 Combi-Cut?

Knauf 100mm Loft Roll 44 Combi-Cut provides a flexible and straightforward insulation solution for cold lofts and pitched roofs insulated at ceiling level. It combines a declared thermal conductivity of 0.044 W/mK, 2.25m²K/W thermal resistance and Euroclass A1 non-combustible fire performance with a practical partially perforated roll format.

Each roll covers approximately 13.89m², while the 1140mm width can be separated into either 570mm or 380mm sections, helping make installation between suitable ceiling joists quicker and more efficient.