White elastomeric sealant.

Easy application by brush or bulk loading caulking gun.

Excellent adhesion to many surfaces.

Sets up quick for coating over.

Low temperature flexibility—specially selected polymers and resins impart
superior low temperature properties to the coating.

Low VOC, water-based, no odor.

Resistant to mold and mildew growth.

UV stable, may be left exposed.

FBC (HVWZ) TAS 139

VOC: 70 g/L MAX

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505MS Karna-Flex WB’s elastomeric properties make it an excellent sealant for making repairs to built-up asphalt roofs, modified bitumen membrane roofs, prepared metal, concrete, spray polyurethane foam and plywood roof system details. Ideal for sealing flashings, curbs and waterproofing metal roof seams, gutters, fasteners, pinholes in metal and skylights. Excellent for sealing flashings on asphalt BUR roofs and modified bitumen membrane roofs. Ideal for sealing around penetrations and roof top equipment. Use in place of flashing cement for repairs to all types of asphalt roofs prior to applying white coatings.

Weight per Gallon: 11.8 lbs
%NV by Weight: 70%
%NV by Volume: 65%
Color: White
Tensile Strength: 40 psi.
Elongation: 500%
ASTM C-734 Low Temp Flex: Pass No Cracking
Recovery: 75% min.

SURFACE PREPARATION:
All surfaces to be sealed must be dry, clean and free from rust, loose coating and caulk, oil, grease and other foreign matter. Remove silicone or other sealants before using.

APPLICATION:General Repairs
505MS Karna-Flex WB should be applied by stiff brush or bulk loading caulking gun, depending on the application. Apply sealer when temperatures are above 40ºF and rain is not forecasted within 24 hours. For sealing flashings and lap seams use fabric reinforcement between layers of 505MS Karna-Flex WB. Apply sealer in a 1/16” to 1/8” width then immediately embed 5540 Resat-Mat polyester fabric into the wet coating. Smooth out fabric then apply another layer of sealer. Some shrinkage may occur and require an additional application of 505MS Karna-Flex WB.

For metal roofing follow these application guidelines:
1. Horizontal Seams and Cracks 1/16” wide or larger.
• Using 550 Patch-N-Go Fleece Tape, adhere tape to crack as directed per product application guidelines. Apply 505MS Karna-Flex WB at an average thickness of 1/16” to completely cover the polyester face of the tape and feather out.
• Using 5540 Resat-Mat, apply a 1/16” thick application of 505MS Karna-Flex WB then immediately embed one ply of 5540 Resat-Mat polyester fabric into the wet coating. Smooth out fabric then apply another layer of 505MS Karna-Flex WB.
2. Screws/Fasteners, Vertical Seams and Cracks less than 1/16”
• Over screws and fasteners apply a dollop of 505MS Karna-Flex WB to completely enclose the screw/fastener with either a 2” wide brush or bulk loading caulking gun.
• Over vertical seams and cracks less than 1/16” wide, back brush a minimum 2” wide application of 505MS Karna-Flex WB at an appropriate thickness of 1/16” to 1/8”.

Note: Allow to cure 24 hours before coating over, if desired. Not intended for use
in ponding areas.

COVERAGE RATE:
505MS Karna-Flex WB is typically applied in a 1/16” to 1/8” thickness depending upon the substrate which equates to a coverage rate of 4 to 8 gallons per 100 sq. ft. When sealing cracks and joints apply in two applications with fabric reinforcement.

Coverage Rates with Fabric Reinforcement:
Approximate Fabric Width 4", 6"
If Mastic Applied at 1/16" thick, two applications expect 25 lineal feet per gallon with 4" fabric and 18 lineal feet per gallon with 6" fabric.
If Mastic Applied at 1/8" thick, two applications expect 12 lineal feet per gallon with 4" fabric and 9 lineal feet per gallon with 6" fabric.

Fastener Coverage:
Place a dollop (swirl coat) over exposed fasteners. Approximate coverage rate is 250 fasteners per gallon.

Do not apply when rain is imminent. Protect from freezing. Sealant must be dried before exposure to water. Do not take internally. If swallowed, do not induce vomiting. Call a physician immediately. KEEP OUT OF REACH OF CHILDREN. Keep container covered when not in use. Do not thin. Dispose of in an environmentally safe manner. Cover air intakes during application and while drying. Not for use on areas that pond water, roofs should have positive drainage.