Celotex Isover


ISOVER Metac is a glass mineral wool ‘slab on a roll’ insulation solution offering thermal and acoustic benefits for pitched roof between-rafter applications. It can also be used as the insulation between the joists in flat roofs.

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  • Pitched Roof - Between Rafters
  • Flat Roof - Between Joists

Product Features

  • Glass mineral wool roll (1200mm wide) supplied in 50-200mm thicknesses
  • Manufactured from a minimum of 50% recycled glass
  • Achieves an A+ generic rating within the BRE Global Green Guide

Product Properties

  • Board / Roll size: Width 1200mm, Length 3200-9300mm
  • Thickness : 50-200mm
  • Material: Glass mineral wool

Product Performance

  • Lambda: 0.034 W/m.K
  • Reaction to Fire: Euroclass A1 Reaction to Fire classification, according to EN 13501-1
  • Weighted sound reduction of 49 dB (Rw), when used in pitched roof rafter applications*

Product Benefits

  • Helps to reduce heat loss within the building envelope and decrease energy costs
  • Weighted sound reduction of 49 dB (Rw)*, delivering excellent external noise reduction compared to other insulation materials. Helps to improve acoustic comfort of homeowners by reducing transmission of external noise from aircraft, trains, road traffic and weather
  • Easy to install – robust ‘slab on a roll’ which is straightforward to handle, cut and install with minimal waste; any off-cuts can be reused. ISOVER Metac doesn’t ‘slump’ when installed & can easily be friction fitted between rafters without additional fixings
  • Non-combustible - achieves a Euroclass A1 Reaction to Fire classification

* Acoustic tests conducted by Salford University to BS EN ISO 10140-2:2010 for pitched roof rafter applications