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Hardrock dual density cut to falls

A range of high performance, dual-density, stone wool insulation boards for warm flat roofs. Suitable for use with most types of roof deck, and with mechanically fastened or adhesively applied single ply and built-up roofing systems, its tapering thicknesses enable falls to be formed on new build and refurbishment projects. Pre-cut mitres for both hips and valleys are available.

Rockwool Hardrock is CE and Key marked in accordance with BS EN 13162.

Non-combustible, achieving a classification of A1 in accordance with BS EN 13501-1.

Rockwool insulation products do not contain blowing agents with an ozone depletion potential (ODP) or global warming potential (GWP), are CFC-HCFC-HFC free and 97% recyclable. They will not react with metal components or cause loss of plasticiser from PVC cables and pipes.

General information
Uniclass 2015
Pr_25_57_06_56 Mineral wool slab insulationPrimary

J41/10 Built-up reinforced bitumen membrane warm deck roof covering

J41/425 Mineral wool (MW) warm deck roof insulation

J42/10 Warm deck roof covering

J42/425 Mineral wool (MW) warm deck roof insulation

Specification data - Mineral wool slab insulation
Product Reference

Hardrock dual density cut to falls

Hardrock dual density cut to falls SPA


___ mm

Standard product features


1200 x 1000 mm.

Thermal conductivity:

0.039 W/mK.

Product Options


  • Plain – For mechanically fastened single-ply membranes.
  • Tissue faced – For hot applied bituminous felts.
  • Scrim faced – For cold adhesive single-ply membranes.


Tapered, with minimum thicknesses from 30 mm. Consult Rockwool Limited to establish requirements to suit roof shape and falls.

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