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Isover Spacesaver Ready-Cut
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Isover Spacesaver Ready-Cut

100 mm thick

Saint-Gobain Insulation UK Variant:
Third party certifications:
  • DoP


    Certificate type

Thermal insulation suitable for use in loft applications (joist level), suspended timber ground floors and flat roofs (between the joists).

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  • Roofs - Pitched Roof Insulation - Loft Insulation
  • Floors - Ground Floor Insulation - Suspended Timber Floors
  • Roofs - Flat Roof Insulation - Between and Under Joists


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 help increase the speed of installation and ensure more efficient delivery and storage. Other products within the range include Spacesaver, Spacesaver Lite and Spacesaver Plus.

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

Product Features

  • Pre-cut to 3 x 386mm or 2 x 580mm widths
  • Manufactured from up to 75% recycled glass
  • A+ generic rating within the BRE Global Green Guide
  • 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 Benefits

  • Thermal Performance - Thermal conductivity of 0.044 W/m.K. Helps to reduce heat loss within the building envelope and decrease energy costs.
  • Easy to Install - Supplied in longer-roll lengths for quick and easy 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 - Achieves a BRE Green Guide rating of A+ which can assist in demonstrating environmental performance in your BREEAM assessments. Manufactured from up to 75% recycled glass on a plant that uses 100% renewable electricity. For further details visit insulation-uk.com/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:

  • Product Datasheet
  • Declaration of Performance
  • Safe Use Instruction Sheet

General information




Glass mineral wool



Pr_25_57_06_30 Flexible glass wool mat insulationPrimary


P10/10 Loft insulation

P10/125 Insulation laid between ceiling ties/ joists

P10/135 Insulation laid across ceiling ties/ joists

Specification data - Flexible glass wool mat insulation Enhanced data

General requirements

Insulation products generally


To EN 13162.

Thermal conductivity at 10°C (maximum)

ISOVER Spacesaver Ready-Cut has a declared thermal conductivity of 0.044 W/m.K under BS EN 13162: Thermal insulation products for buildings. Factory made mineral wool (MW) products.

0.044 W/m.K.

Thickness (minimum)


100 mm.


Manufacturer's standard.

Consult manufacturer for details.

Fire performance

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

Recycled content

Up to 75%.

Thermal resistance


2.25 m²K/W.


Information regarding storage, installation and handling of ISOVER products, or health and safety information, can be found on the manufacturer's website.

Manufacturer's standard.

Third party product certification

ISO 9001; ISO 14001; BES 6001 Rating “Good”; BRE Global Green Guide Rating A+; EUCEB certified.

  • Manufactured under Quality Management Standard – ISO 9001.
  • All ISOVER products are manufactured under Environmental Management System – ISO 14001. BES 6001 Rating “Good” - The Framework Standard for Responsible Sourcing.
  • Achieves an A+ Green Guide rating for glass mineral wool insulation (ref 815320002) that can assist in demonstrating the environmental performance within BREEAM assessments.
  • EUCEB certified, demonstrating Saint-Gobain Insulation's mineral wool fibre products conform with Note Q of Regulation (EC) No 1272/2008.

Environmental information

Recycled content

ISOVER Spacesaver Ready-Cut is manufactured from up to 75% recycled glass

75 %

Third party certifications


Declaration of Performance (DoP): Isover Spacesaver family

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