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Interfloor Ltd Third party certifications:
  • QA Certificate

    QA Certificate

    Certificate type

Underlay suitable for stretch-fit installation of carpets.

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Underlay suitable for stretch-fit installation of carpets.

Features and benefits:

  • Sponge rubber textured flat.
  • Suitable for underfloor heating.
  • End use classification (to BS 5808): HC/U, heavy contract use.

General information


Pr_35_57_11_13 Cellular rubber underlaysPrimary


M50/170 Carpeting

M50/25 Carpeting

Product range

Carpet Underlays

Specification data - Cellular rubber underlays

Product Reference

Defender, TADEF3

Standard product features

Nominal square weight:

3017 g/m².

Nominal density:

495 kg/m³.

Roll area:

15.07 m² (1.33 x 11.33 m).

Nominal roll weight:

45.5 kg.

Nominal thickness:

6.1 mm.


No objectionable odour.

Colour/ backing:

Green/ printed Textron® backing.

Impact sound reduction (Delta Lw):

31 dB.

Emissions (US Carpet and Rug Institute):

Meets low VOC emission criteria. Certified GLP051 Cat CC2 PU.

Thermal resistance:

0.8 togs.

Antimicrobial and mildew resistance:


Technical characteristics:

  • Work of compression (minimum 50 J/m²): 140 J/m².
  • Retention of work of compression (minimum 40%): 85%.
  • Loss in thickness after dynamic loading (maximum 15%): 3.5%.
  • Loss in thickness after static loading (maximum 15%): 4.5%.
  • Breaking strength (length/ width) minimum 40N: 182/ 126 N.
  • Extension under force (length/ width) maximum 10% at 40N: 2.2/ 1.0%.
  • Resistance to cracking (not greater than 50 mm): Pass.

Test performance to US standards:

  • CFD (Compression Force Deflection): 4.9 PSI @ 25% deflection.
  • CFD (Compression Force Deflection): 13.7 PSI @ 50% deflection.
  • CFD (Compression Force Deflection): 32.2 PSI @ 65% deflection.
  • Recommended use: Extra heavy commercial class III.


  • Hot metal nut test: Low radius of ignition.
  • US Methenamine Pill Test: Pass.
  • US Smoke Chamber Test: Pass.
  • US critical radiant flux: NFPA Class I.
  • Reaction to fire classification (tested in conjunction with Axminster 80:20 carpet): Cfl-s1.
  • China National FR Test (at China National Test Centre): Bf1 – s1,t1.
  • Russian GOST FR Test Classification: KM3.

Green credentials:

  • Recyclable: At the end of the underlay's useful life it can be 100% recycled. MR 2.0: points available. It can be recycled.
  • Recycled content: Contains not less than 3% post-consumer recycled material. MR 4.0: points available. Recycled content.
  • Indoor air quality: Meets or exceeds the industry standard for indoor air quality as established by the CRI Green Label Programme. IEQ 4.3: points available. Product is Green Label Plus certified.
  • Regional materials: Production Facility, Haslingden, BB4 4LS, UK. Where used within 500 miles of production facility, MR 5.0: points available.

Third party certifications

  • CRI: Green Label Plus

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