Kerabit LESSNOX is a torchable multi-layer top membrane for multiple roofing that breaks up the hazardous nitric oxides.

The carrier consists of polyester felting. The bottom surface of the product is coated with torch-on modified bitumen and the top surface with light grey slate.
This product can be used as the top membrane of a multi-layer membrane.

See the LESSNOX-video (texts in Finnish) >



Manufacturer / Manufactured for Nordic Waterproofing Oy, Lohja plant
Country of origin Finland
Conformity marking CE
Reaction to fire Manufacturer’s fire testing certificate
Fire Classification


Manufacturer’s declaration of conformity Kerabit modified bitumen roofing materials
Quality control Quality control agreement between the Plant and Eurofins Expert Services Oy
Nominal thickness n. 4,4 mm
Nominal weight 5000 kg/m²
Weight of the supportive layer 170 g/m² (+/- 10 g/m²)
Supportive layer polyester
Surface type

Light grey LESSNOX® slate

Rolls size 1 x 8 m / 8 m²
Colours Light grey
Packages / pallet 24 rolls
Weight / package 40 kg
Weight / pallet 985 kg


This product can be used as a top membrane of a multi-layer roofing.

Handling and storage

Modified bitumen membranes are to be stored on pallets in a dry and cool place. Use a plastic hood or tarpaulin for protection. When the outdoor temperature exceeds +40°C, the rolls must be protected from sunlight.