Isover Spacesaver Ready-Cut

Spacesaver Ready-Cut is a glass mineral wool roll, which is pre-cut to fit between common joist spacing at ceiling level. It is supplied in longer-length rolls to increase efficiency by reducing the number of rolls required to be delivered, stored and opened during installation.

Other products within the range include Spacesaver, Spacesaver Lite and Spacesaver Plus.

Spacesaver Ready-Cut can also be used between the joists in suspended timber ground floors and flat roofs.

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Product Features

  • Pre-cut to 3 x 386mm or 2 x 580mm widths
  • Manufactured from up to 82% recycled glass
  • Achieves Eurofins Gold certification, the highest accreditation for indoor air quality

Fire Classification

Euroclass A1 Reaction to Fire classification according to EN 13501-1.

Product Specification

Thickness (mm) Length (m) Width (m) λD Declared thermal conductivity (W/m.K) RD Declared thermal resistance (m².K/W)
100 12.18 3 x 0.386 0.044 2.25
100 12.18 2 x 0.580 0.044 2.25
150 8.05 3 x 0.386 0.044 3.40
150 8.05 2 x 0.580 0.044 3.40
200 5.20 2 x 0.580 0.044 4.50
200 5.20 3 x 0.386 0.044 4.50

Product Benefits

  • Thermal Performance - Thermal conductivity of 0.044 W/m.K. Helps to reduce heat loss within the building envelope and as a result decreases energy costs. 
  • Isover Spacesaver Ready-Cut has Eurofins Indoor Air Comfort® Gold Certification - the highest accreditation for indoor air quality.
  • Ease of Install - Supplied in longer-roll lengths for speed and ease of installation, maximising on-site efficiency. The rolls are pre-cut (3 x 386 and 2 x 580mm widths) to fit common joist spacing.
  • Fire Classification - Achieves a Euroclass A1 Reaction to Fire classification, according to EN 13501-1.
  • Sustainability - Manufactured from up to 82% recycled glass with all electric equipment in the plant powered by 100% renewable electricity. For further details visit isover.co.uk/CSR

Key Considerations

When using Isover Spacesaver Ready-Cut, you need to satisfy yourself that use of the product meets all relevant national Building Regulations and guidance as well as local, national and other applicable standards relevant for your construction or application, including requirements in relation to fire and applicable height restrictions.


Please refer to the following product documents: