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Iso-Step® Floor Underlayment

(10 customer reviews)



Our Iso-Step® Floor Underlayment is engineered to provide superior impact sound insulation and better performance over other sound control materials. It may be installed over a wood or concrete sub floor and under a wide range of flooring finishes. Installing Iso-Step® underneath the entire flooring assembly short circuits impact noise to combat footfall and structure borne sound and vibration.

Impact noise is a structure borne sound created when two objects collide. This impact energy creates vibrations that resonate through the materials in the structure. It also creates airborne sound. This is often realized in the real world as a ‘neighbor noise’ generated from someone walking on the floor above or other activities. The Iso-Step® acoustic floor underlayment should be placed underneath the finished flooring and cover the whole floor. This provides an isolation layer to help prevent structural sound from passing through the completed assembly.

Manufactured in the USA using recycled material, this rubber floor underlayment has been rigorously field tested with proven results. It can be installed under most types of grouted, glued, and floating floors, including ceramic tile, stone, marble, brick, pavers, hardwood, engineered wood, laminate, parquet, luxury vinyl tile and carpet.

Our Iso-Step® Floor Underlayment is available in thicknesses of 2 mm, 5 mm, 10 mm and 12 mm. With a Delta IIC from 16 to 25, we offer a rubber floor underlayment well-suited to meet any job requirement.


  • Fast installation
  • Compatible with most floor finishes
  • Manufactured from recycled rubber
  • Can thin-set tile and stone direct to product per ASTM C627
  • Rated extra heavy by the Tile Council of North America
  • Passes VOC Washington State IAQ Test (ASTM D5116)
  • 94% post-consumer recycled content
  • Made in the USA

Technical Information for Iso-Step® Floor Underlayment:

  • Thickness: 2 mm, 5 mm, 10 mm, 12 mm
  • Roll Size: 48″ x 75′ (2 mm), 48″ x 30′ (5 mm), 48″ x 15′ (10 mm), 48″ x 15′ (12 mm)
  • Roll Weight: 120 lbs. (2 mm, 12 mm), 100 lbs. (5 mm, 10 mm)
  • Material: 92% resilient recycled rubber
  • Physical Data
    • Density: 0.72 g/ cubic cm min. (ASTM D297)
    • Tensile Strength: 80 psi, min. (ASTM D412, Die C)
    • Tear Strength: 30 ppi, min. (ASTM D624)
    • Elongation: 50%, min. (ASTM D412, Die C)
    • Compression: 20-30%, 85%, min. (at 100 psi recovery)
    • Shore A Hardness: 40 durometer (ASTMD2240)
    • Flexibility: 1 factor, max. (ASTM F147)
    • Compression Set B, 25% Deflection, 158 degrees/22 hrs: 40% Max (ASTM D395)
    • Coefficient of Friction: 1.2 (ASTM D1894)
    • Crack Resistance: High Performance (ASTM 118.12 5.4)
    • Tolerance:
      • Width: +3/4″ – 0″
      • Length: +1% – 0″
      • Thickness: +/- 0.3 mm
    • Installation: Refer to installation guides posted in the documents tab.
 Acoustic Test Results of Common Assemblies
ThicknessAssembly DescriptionSTCIIC
2 mmWood flooring, 1 layer 2 mm, 8″ reinforced concrete slab, suspend ceiling7272
2 mmLVT (luxury vinyl tile) flooring, 1″ gypsum concrete, 1 layer 2 mm, wood truss, resilient channels, suspended ceiling6350
5 mmLaminate flooring, 1 layer of 5 mm, 7″ reinforced concrete slab, no ceiling5558
5 mmCeramic tile, cement board, 1 layer 5 mm, wood truss, resilient channels, suspended ceiling6452
10 mmPorcelain tile, 1 layer 10 mm, 8″ reinforced concrete slab, no suspended ceiling5753
12 mmPorcelain tile, 1 layer of 12 mm, 8″ reinforced concrete slab, no suspended ceiling5753


For more information on our Iso-Step® Floor Underlayment,
call us at 800.782.5742 or contact our sales department.

Customer Reviews

10 reviews for Iso-Step® Floor Underlayment

  1. `NV Build

    Quality product that is easy to work with.

  2. Andrew Waldeck

    Fantastic density, easy to roll out. studio complete, works like a charm.

  3. James

    easy installation……works as advertised……

  4. Verified Customer

    This is an excellent product to help reduce the sound transmission from the floor. The level of sound absorbtion you get is determined by the thickness of the underlayment.

  5. Verified Customer

    This floor underlayment works exactly as advertised. It reduced sound transmission and stabilized a cracked and squeaky concrete topper in my loft. I wouldn't hesitate to buy it for my next project or to recommend it to anyone looking to improve (dampen) sound transmission.

  6. Verified Customer

    it should provide excellent sound insulation!

  7. Verified Customer

    Used in a new home to isolate 1st floor from basement. Worked as expected. Thank you.

  8. Verified Customer

    The density is far above anything you can buy in any chain store. Sound muffling is great. It is porous so if moisture barrier is needed will have to add a layer. A little cumbersome to work with because of the weight, but that is expected. Could benefit from having a grid, or lines to assist in straight cuts.

  9. Verified Customer

    Awesome product, easy to use. Works great in a home gym.

  10. Verified Customer

    I would recommend this product to anyone that lives in a condo on the second floor. Works great. i hear such a difference. love it!