Isover Spacesaver Plus

Spacesaver Plus is a glass mineral wool roll for loft applications with improved thermal performance, compared to other Spacesaver products. The rolls are pre-perforated to fit between common joist spacing at ceiling level. Other products within the range include Spacesaver, Spacesaver Ready-Cut and Spacesaver Lite.

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

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Product Features

  • Glass mineral wool rolls pre-perforated to 3 x 386mm and 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 7.00 1.16 0.040 2.50
150 4.67 1.16 0.040 3.75
200 3.50 1.16 0.040 5.00

Product Benefits

  • Thermal Performance - Thermal conductivity of 0.040 W/m.K. Helps to reduce heat loss within the building envelope and as a result decreases energy costs.
  • Isover Spacesaver Plus has Eurofins Indoor Air Comfort® Gold Certification - the highest accreditation for indoor air quality.
  • Ease of Install - The rolls are pre-perforated (3 x 386 and 2 x 580mm widths) to fit common joist spacing, or can be used full width for quicker coverage.
  • 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 Plus, 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: