Skip to main content
Isover – Acoustic Insulation Solutions
  • Visit the iHub
  • Contact Isover
  • Home
  • About Us
    • About Us
    • About Saint-Gobain
    • About Isover UK
    • Meet The Exec Team
    • Saint-Gobain Multi-Comfort
    • Sustainability & Environment
      • BES 6001 - Responsible Sourcing
      • Built Environment
    • Contact Isover
  • Solutions
    • Solutions
    • Vario® Airtightness and Moisture Management
    • Energy Efficiency
      • Making the Ultimate move
    • Built In Sound Control from Isover
    • Applications
      • External Walls - Masonry
      • External Walls - Timber Frame
      • Internal Floors
      • Internal Partition Walls - Metal Stud
      • Internal Partition Walls - Timber Stud
      • Pitched Roof - Joist
      • Pitched Roof - Rafter
      • Separating Walls - Masonry
      • Separating Walls - Timber Frame
  • Products
  • Downloads
  • Apps & Tools
    • Apps & Tools
    • iHub
    • iSelector
    • dBstation
    • Videos
    • FAQ
    • Building Regulations
  • News & Blog
  • Case Studies
  1. Home
  2. Solutions
  3. Applications
  4. Pitched Roof - Rafter

Pitched Roof - Rafter

Insulation for habitable loft spaces.

Building extra living areas within the attic is a great way to maximise the space within a house without increasing the footprint.

To keep a lid on heating bills, ensure compliance with building regulations and maximise occupant comfort, it is essential that habitable loft spaces are well insulated and airtight.  Isover’s solution for this application features Metac insulation in combination with the Vario® airtightness and moisture management system.

Metac is a glass mineral wool ‘slab on a roll’ insulation which combines excellent thermal and acoustic performance with ease of installation. It offers a more cost effective solution for pitched roof rafter applications than many alternative insulation materials.

Vario® XtraSafe is an innovative ‘smart’ vapour barrier which ideal for use within loft spaces. It delivers airtightness alongside active moisture management to help you meet and exceed the latest Building Regulations and protect the building fabric.

Building Regulations

Country Building Regulation New Dwellings - Required U-value Renovation - Required U-value
England New Dwellings – Part L 0.20 W/m2K 0.18 W/m2k Conversion
0.18 W/m2k Extension
Wales New Dwellings – Part L 0.15 W/m2K 0.18 W/m2K Conversion
0.15 W/m2K Extension
Scotland New Dwellings – Section 6 0.15 W/m2K 0.25 W/m2K Conversion
0.18/0.13 W/m2K Extension*

* Lower U-value is required when existing wall and roof U-values are less than 0.70 and 0.25 respectively

Isover Solutions

The table below gives you some examples of how Metac can be used to achieve a defined U-value. For additional options, or for further guidance, please contact our Technical Advice Centre on 0115 945 1143
U-value achieved (W/m²k)* Insulation between rafters @ 600m centres Insulation below rafters
0.19 125mm Metac 53mm Gyproc ThermaLine PIR
0.18 125mm Metac 63mm Gyproc ThermaLine PIR
0.17 175mm Metac 50mm Metac between counterbattens plus 12.5mm Gyproc WallBoard
0.16 175mm Metac 53mm Gyproc ThermaLine PIR
0.15 175mm Metac 63mm Gyproc ThermaLine PIR
0.14 200mm Metac 53mm Gyproc ThermaLine PIR
0.12 200mm Metac 78mm Gyproc ThermaLine PIR

* Based on 50mm wide rafters

Related

Metac

Vario® Airtightness and Moisture Management

Pitched Roof - Rafter

Application - Pitched Roof - Rafter

Technical Support

In addition to providing a full range of insulation solutions, Isover also offers comprehensive technical support and advice, for more information click here.
  • © 2018
  • Sitemap
  • Accessibility
  • Terms of Use
  • Isover Policies
  • Saint-Gobain Policies
Saint Gobain Logo
Back to Top