Glass Mineral Wool - Knauf Insulation Loft Roll 40

Knauf Insulation Loft Roll 40


Pitched roofs at ceiling level


Glass Mineral Wool


Loft Roll 40 is a glass mineral wool roll, designed for insulating cold pitched roofs at ceiling level, with a thermal conductivity of 0.040 W/mK. It offers the best thermal performance in our Loft Roll range.

Loft Roll 40 is non-combustible with the best possible Euroclass A1 reaction to fire classification, and is manufactured using our unique bio-based binder, ECOSE® Technology.


  • Cost effective solution for cold lofts where the thickness of insulation is unrestricted.
  • Combi-cut products are supplied partially perforated, allowing them to be used between joists or uncut as a full-width roll, maximising efficiency during installation.
  • Manufactured in two different options; long lengths to allow quick and simple installation maximising efficiency.

For historical versions of product documentation, or documents relating to any discontinued products, please contact us with your requirements at [email protected].  



Thickness (mm) Length (mm) Width (mm) Thermal Conductivity (W/mK) R-value (m²K/W) Area per roll (m²) Euroclass Reaction to Fire Classification Roll Type Quantity per pack Packs per pallet
100 11250 1140 (2 x 570mm/3 x 380mm) 0.040 2.5 12.830 A1 Combi-cut 1 24
150 7530 1140 (2 x 570mm/3 x 380mm) 0.040 3.75 8.580 A1 Combi-cut 1 24
200 4850 1140 (2 x 570mm/3 x 380mm) 0.040 5 5.530 A1 Combi-cut 1 24

Certification & Memberships

Eurofins Gold Eurofins Gold
Euroclass A1 Reaction to Fire Classification Euroclass A1 Reaction to Fire Classification
Green Guide Rating A+ Green Guide Rating A+
CE Marking CE Marking
EN 15804 EN 15804
Made in Britain Made in Britain
DECLARE 'Red List Free' DECLARE 'Red List Free'

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