MB TU70 Layfast SBS Modified Asphalt Reinf. 70# Underlayment, 36 Rolls - MB Technology TU70, 70# Layfast SBS Modified Asphalt Underlayment w/ Fiberglass Mat. Use under Tile/Metal Roofs where two layers of 30# is specified. Mechanically fastened. 3.3x32.5 ft/Roll. 36 Rolls/Pallet. Price/Pallet. (ship leadtime 2-4 business days)
MB TU70 Layfast SBS Modified Asphalt Reinf. 70# Underlayment, 36 Rolls
$3,520.00 SALE $2,257.95
(Savings: $1,262.05)
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MB Technology TU 70, 70# Layfast SBS modified asphalt underlayment. Reinforced with fiberglass mat, used under tile or metal roofs. Ideal for applications where two layers of 30# is specified. Mechanically fastened. Mechanically fastened. 3.31 ft. x 32.50 ft. Rolls. 36 Rolls/Pallet. Price/Pallet.

Ordering Notes:

  • Shipping leadtime: 2-4 business days.


The open mesh construction of the asphalt coated fabric allows the surface coatings to penetrate through and interlock, thereby providing a firm mechanical bond between coatings, and insuring long life of the application. This strong elastic interlocking system is very pliable and prevents rupture due to expansion and contraction of the applied surfaces.


Asphalt-saturated fiberglass fabric is traditionally used for hot-process coatings. Asphalt coated cotton fabric is useful for tennis court patches, insulation and pipe wrap, roofing, dampproofing and waterproofing and wherever construction is exposed to the extreme elements.


  • SBS modified asphalt underlayment/base. Reinforced with fiberglass mat.
  • Much higher tensile strength than standard asphalt cotton.
  • 20 x 10 thread count provides larger mesh openings, improving bitumen saturation and penetration.
  • Suitable for Hot or Cold applications.
  • High Tensile strength yet very lightweight.
  • Will not rot, mold or mildew. 
  • Meets ASTM D1668, Type I & Fed. Spec. HH-C-466b
  • Dimensionally stable and free of defects.
  • Will unroll and handle easily in normal installation.
  • The asphalt saturated fabric unrolls easily, without distortion.
  • The treated fabric can be applied smoothly and without wrinkles.


  • Higher tear resistance
  • Increased longevity
  • More protection
  • More water resistant


  • Weight: 88 lbs./roll
  • Width/Length: 39-3/4 inch / 64 ft. 4 inch
  • Reinforcement: Fiberglass
  • Application: Mechanically fastened
  • Coverage: 1 squares/roll
  • Rolls Per Pallet: 36



Email us at sales@bestmaterials.com or
Call us at 1-800-474-7570 or 602-272-8128
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similar product terms: SBS modified asphalt underlayment, shingle roofs, layfast underlayment, layfast SBS, mb technology, roof underlayment, steep roofing, valleys, eaves, tile roofs, metal roofs, high pitched roofs

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