About LIBERTY™ Self‑Adhering Base/Ply Sheet

LIBERTY™ SBS Self-Adhering Roofing Systems are applied without torches, open flames, or hot asphalt, and are suitable for many primed substrates. LIBERTY™ Self-Adhering Base/Ply Sheet is a self-adhering modified bitumen roofing membrane intended to be used as either a base sheet for LIBERTY™ Self-Adhering Cap Sheet or as a ply sheet in modified bitumen roofing systems, providing long-lasting protection on low-slope roofs.

  • Convenient self-adhering installation eliminates open flames, hot asphalt, or dangerous chemicals on your roof
  • Reinforced with a glass mat which is coated with polymer-modified asphalt
  • Installed as a base sheet with LIBERTY™ Self-Adhering Cap Sheet or ply sheet for modified bitumen systems
  • Up to a 20-year limited warranty against manufacturing defects depending on system1


This product has earned the Good HouseKeeping Seal.


This product can be used to comply with certain FORTIFIED Roof™ requirements. Visit gaf.com/fortified and current FORTIFIED Home™ Standard available at fortifiedhome.org for details. Applicable in the U.S. only.

1See Limited Warranty on LIBERTY™ Self-Adhering Materials for complete coverage and restrictions.

Key Benefits

Serves as a Base Sheet for LIBERTY™ Self-Adhering Cap Sheet or Ply Sheet for modified bitumen roofing systems.

1See Limited Warranty on LIBERTY™ Self-Adhering Materials for complete coverage and restrictions

The LIBERTY™ SBS self-adhering roll roofing system

This LIBERTY™ roofing system from GAF not only simplifies installation with convenient peel-and-stick components, it’s also available in nine popular colors to complement your Timberline® or other GAF asphalt shingles.

GAF LIBERTY™ product warranty

When installed as a complete system, our LIBERTY™ Limited Warranty covers up to twenty years of manufacturing defects available on select systems.* System guarantees covering material defects and workmanship errors are also available for purchase for approved systems installed by GAF certified contractors.**
*Exclusions apply. See Limited Warranty on LIBERTY ™ SBS Self-Adhering Materials for complete coverage and restrictions.
**See Low-Slope Addendum to the System Plus Limited Warranty, Low-Slope Addendum to the Silver Pledge ™ Limited Warranty, and Low-Slope Addendum to the Golden Pledge® Limited Warranty for complete coverage and limitations
Thumbnail of video showing GAF LIBERTY™ Self-Adhering Roofing System step by step

LIBERTY™ step-by-step installation video

Step-by-step instructions show you how to install a LIBERTY™ low-slope roofing system.

LIBERTY™ SBS Self-Adhering 2-Ply Roofing System Installation — Step-by-step***

  1. GAF roof contractor repairing damage

    Step 1

    Inspect the roof, and repair or replace damaged areas.
  2. GAF roofing contractors rolling on LIBERTY Asphalt Primer.

    Step 2

    Apply LIBERTY™ Asphalt Primer at a rate of a 1/2 gallon per 100 sq. ft.
  3. GAF contractors installing LIBERTY SBS Self-Adhering Base/Ply on flat roof.

    Step 3

    Install LIBERTY™ Self-Adhering Base/Ply.
  4. Contractor applying LIBERTY Flashing Cement on exposed roof flange.

    Step 4

    Install edge flashing at all eave and rake edges, and apply LIBERTY™ Flashing Cement on exposed flange.
  5. GAF roofing contractors installing LIBERTY SBS Self-Adhering Cap Sheet on a flat roof.

    Step 5

    Install LIBERTY™ Self-Adhering Cap Sheet.

  6. Step 6

    Apply LIBERTY™ Flashing Cement on end laps, on exposed sheet and set the overlap back into place when applicable.
  7. Finished flat residential roof with GAF LIBERTY system.

    Step 7

    Clean up by removing tools, unused materials, and other debris. Plan on inspecting roof annually if possible.

***See application instructions for complete details. 

Product Documentation

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