LIBERTY Flashing Cement Specs

      LIBERTY Flashing Cement Docs

      LIBERTY Flashing Cement Videos

      About LIBERTY™ Flashing Cement

      Seal a variety of roof materials with LIBERTY Premium SBS Flashing Cement. This bonding agent works with shingles, metal, built-up asphalt, SBS modified bitumen membrane end laps and perimeter edges, metal-edge flashing, gutter seams, and air conditioning ducts. This product provides bonding strength and flexibility while being easily applied with a 1/4” notched trowel or squeegee.

      A cold-applied bonding agent for a wide variety of roofing components

      LIBERTY™ Flashing Cement is ideal for a wide variety of sealing, bonding, and repairing applications in areas where temperature-related expansion and contraction occurs.


      Trowel-grade consistency makes it ideal for flashing details, attaching membrane to steep slopes and parapet walls, and a variety of roofing and waterproofing repairs.

      Strength and Flexibility

      This product offers excellent bonding strength and high flexibility to accommodate temperature-related expansion and contraction of the roof system.

      Convenient Application

      This product can be applied with a 1/4” notched trowel or squeegee, and it maintains excellent low-temperature flexibility.


      Based on applicator type

      Membrane Flashing

      Apply cement at 1 to 2 gallons per square (.4 – .8 L/m2) to substrate only.


      Apply cement to surface and install glass, polyester fabric, or asphalt-coated cotton fabric into cement. Repeat as wanted. Finish with a final layer of cement.


      Prime metal. Set metal flanges into a full bead of 1/8” (3mm) thickness. Apply cement between joints and apply pressure so that a bead of cement is visible at joint edge.


      Apply cement at a 1/8 inch (3 mm) to 1/4 inch (6 mm) thickness, working the cement into the opening or crack and spreading beyond repair area approximately 2” – 4” (51 – 102 mm).
      LIBERTY™ Installation — Step-by-step*
      GAF roof contractor repairing damage

      Step 1
      Inspect the roof, and repair or replace damaged areas.

      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.

      GAF contractors installing LIBERTY SBS Self-Adhering Base/Ply on flat roof.

      Optional (for 2-ply system):
      Install LIBERTY SBS Self-Adhering Base/Ply.

      Contractor applying LIBERTY Flashing Cement on exposed roof flange.

      Step 3
      Install edge flashing at all eave and rake edges, and apply LIBERTY Flashing Cement on exposed flange.

      GAF roofing contractors installing LIBERTY SBS Self-Adhering Cap Sheet on a flat roof.

      Step 4
      Install LIBERTY SBS Self-Adhering Cap Sheet.

      Finished flat residential roof with GAF LIBERTY system.

      Step 5
      Clean up by removing tools, unused materials, and other debris. Plan on inspecting roof annually if possible.

      *See application instructions for complete details.

      See similar products

      Can of LIBERTY Asphalt Primer by GAF.
      LIBERTY™ Asphalt Primer

      General-purpose foundation coating for a variety of roof materials

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      GAF LIBERTY Cap Sheet roofing membrane for low-slope areas.
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      Granule-surfaced roofing membrane for low-slope areas

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      GAF LIBERTY Base Sheet roofing membrane for modified bitumen systems.
      LIBERTY™ Base Sheet

      Membrane used as a base for LIBERTY™ Cap Sheet or as a ply sheet for modified bitumen systems

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