
Product Data Sheet
FLEX FB LOW RISE ADHESIVE
PRODUCT DESCRIPTION
Flex FB Low Rise Adhesive is a two component, low rise polyurethane adhesive designed to attach Flex
Fleeceback Roofing Membranes to a variety of approved substrates in accordance with current Flex Roof
Details and Specifications.
APPLICATION
Install only as much roof membrane adhered with Flex FB Low Rise Adhesive as can be covered and
made watertight during that working day. The substrate must be clean, smooth, dry and free of sharp
edges, loose and foreign materials, oil, grease, and other contaminants. Proper equipment must be used to
install Flex FB Low Rise Adhesive. Apply the adhesive on the substrate in beads spaced at a maximum
of 12” (300 mm) on center with a ¾” – 1” (19.00 mm-25.4 mm) wide bead. It is important to allow the
adhesive to rise in height. Before a skim coat develops on the adhesive mate the Flex fleeceback roofing
membrane to the substrate. Immediately after setting the membrane in the Flex FB Low Rise Adhesive, it
is required to apply continuous pressure to the bonded membrane using a roller (maximum weight 150
lbs. – 68 kg). It is important that freshly installed membrane remain in contact with the substrate and Flex
FB Low Rise Adhesive until the adhesive sets to ensure proper adhesion.
COVERAGE RATE
Rate is average coverage based on approved, smooth, non-porous surface with a ¾” to 1” (19-25 mm)
wide bead.
Bead Spacing Coverage Rate: ft²/gal (m²/L)
12” o.c. 170-200 (4.1-4.8)
6” o.c 90-120 (2.2-2.9)
4” o.c. 60-90 (1.4-2.2)
These are typical coverage rates that are applicable when the Flex FB Low Rise Adhesive is properly
mixed with a 1:1 ratio and applied in the appropriate bead spacing in a serpentine pattern at a bead width
of ¾” to 1” (19 mm to 25.4 mm). Coverage rates may vary on substrate type and condition as well as
increasing the bead spacing.
REACTION TIME
When applying the Flex FB Low Rise Adhesive, the Flex FB membrane must be placed in the adhesive
while it is still wet and tacky (before it reaches tack free state). The membrane may be placed into the
adhesive shortly after it has reached its maximum rise typically after 2-3 minutes.
_____________________________________________________________________________________________________
Flex Membrane International Corp. 2670 Leiscz’s Bridge Road, Suite 400, Leesport, PA 19533
Tel: (610) 916-9500 Fax: (610) 916-9501 www.FlexRoofingSystems.com
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APPROVED SUBSTRATES
Structural Concrete, Plywood and OSB Decking, Cementitious Wood Fiber, Gypsum, LWIC (cellular or
air entrained lightweight concrete), existing Asphalt and Modified Bitumen (smooth surface or mineral
surface), SBS base sheets, polyisocyanurate insulation board, HDWF cover board, DensDeck cover
board, Securock cover board.
NON-APPROVED SUBSTRATES
Coal Tar Pitch BUR, Expanded or Extruded Polystyrene Foam insulation board, Fiberglass insulation
board, and Perlite insulation board.
PACKAGING
Boxes:
Part 1- 5 gal bag in the box and Part 2 – 5 gal bag in the box. Specifically designed to be dispensed using
the PaceCart 2 ™dispenser. The Pace Cart 2 ™dispenser pumps the Flex FB Low Rise Adhesive parts 1
and 2 simultaneously to a static mixer which allows a properly mixed bead of adhesive to be applied to
the receiving substrate.
Cartridge:
1500 ml cartridge kit (750 ml part 1 and 750 ml part 2). Cartridges can be dispensed using various Flex
approved hand or multi-bead electric dispensing units. The dispensing units extrude Part 1 and Part 2
simultaneously through a static mixer which allows a properly mixed bead of adhesive to be applied to the
receiving substrate.
Note: PaceCart 2 ™ is a registered trademark of OMG, Inc.
CAUTIONS
·
Flex FB Low Rise Adhesive may be installed only when ambient conditions, and bonding
substrates and membranes, exceed 40°F, (4° C) and are rising.
·
Store in original and unopened containers at temperatures between 60°F (15.6°C) and 80°F
(26.7°C) prior to use.
·
Do not store in direct sunlight.
·
Do not allow to freeze.
·
Do not expose to moisture.
·
Ship and store product with handle side up and keep caps of nozzle closed tightly.
WARNING
Review applicable MSDS sheet prior to use. Personnel that are sensitive/allergic to isocyanate or
polyurethane should not work with Flex FB Low Rise Adhesive. Avoid contact with eyes. Avoid
breathing vapors. Avoid contact with skin. Use caution when removing caps from cartons. Do not burn
empty containers. Dispose of in accordance with local, federal, and state regulations. For use with Flex
Fleeceback Roof Membranes only.
_____________________________________________________________________________________________________
Flex Membrane International Corp. 2670 Leiscz’s Bridge Road, Suite 400, Leesport, PA 19533
Tel: (610) 916-9500 Fax: (610) 916-9501 www.FlexRoofingSystems.com
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