Supafil 34 Cavity Wall Insulation

Supafil 34 is BBA Certified

High performance blown glass mineral wool cavity wall insulation for masonry cavity walls - For Specialist Contractors only.




Supafil 34 Cavity Wall Insulation has a thermal conductivity of 0.034W/mK when tested to BS EN 14064 (Lambda 90/90)



Supafil 34 Cavity Wall Insulation is classified as Euroclass A1 to BS EN 13501-1


Supafil 34 Cavity Wall Insulation is an unbonded, non-combustible glass mineral wool insulation which requires no mixing on site.


  • Lambda 90/90

  • Low thermal conductivity

  • Tried and tested Supafil technology

  • Rigorously tested by the BBA

  • Nationwide network of approved installers

  • Low environmental impact

  • 25 year guarantee

  • Installed in any weather


The British Board of Agrément Certificate for Supafil 34 Cavity Wall Insulation approves the application and installation procedure for this product. This product complies with the relevant sections of the:

  • Building Regulations (England and Wales)
  • Building Standards (Scotland)
  • Building Regulations (Northern Ireland)

The certificate covers use in masonry cavity walls with a minimum 90 mm cavity width, up to 12m in height, as detailed within the BBA certificate and may be installed up to 25m subject to a satisfactory inspection of the wall construction and installation approval by Knauf Insulation, and in any exposure zone.


Supafil 34 Cavity Wall Insulation conserves energy and therefore assists in reducing demand for fuels for the heating and air-conditioning of buildings. As a result, it reduces the emissions of the major greenhouse gas, CO2. The energy and CO2 emissions saved by the product in use vastly outweighs those generated in it’s manufacture.

  • Glass Mineral Wool has an A+ rating in the BRE Green Guide to Specification
  • Zero ODP
  • Zero GWP
  • Manufactured using recycled glass
  • Compression packed to reduce vehicle movements and fuel related COemissions

Supafil 34’s manufacture has a low impact on the environment and is classified as Zero ODP and Zero GWP.


Vapour resistence - resistivity

Supafil 34 offers negligible resistance to the passage of water vapour and has a vapour resistivity of 7.00 MN.s.g.m.

Moisture resistance

Tests by the British Board of Agrément confirm that Supafil 34 Cavity Wall Insulation will not transmit water to the inner leaf. Nor will it transmit moisture by capillary action across the cavity or from below damp proof course level. This has been confirmed by independent research conducted for the Energy Saving Trust, which shows that cavity wall insulation does not add to the risk of water penetration. 

Handling and storage

Supafil 34 is supplied in polythene packs which are designed for short term protection only. For longer term protection on site, the product should either be stored indoors, or under cover and off the ground and should not be left permanently exposed to the elements.

Product Data

Weight per bale (kg)Thermal Conductivity (W/mK)Pack DimensionsPacks per palletPacks per Trailer
15.5 0.034 1200x550x250 28 24

All dimensions are nominal

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