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421 Mod Bit Adhesive - Trowel Grade

421 Mod Bit Adhesive - Trowel Grade

Mule-Hide #421 Mod Bit Flashing Adhesive – Trowel Grade is a high quality formulation for use as a cold-applied bonding agent for SBS modified bitumen roof systems. Heavy, “trowel-grade” consistency makes this product ideal for flashing details, attachment of membrane to steep slopes and parapet walls and a variety of waterproofing repairs, especially at moving joints where its flexibility and elasticity make it superior to standard plastic cements. In addition, the formulation is non-destructive to asphalt based roofing membranes.

System

ModBit
M&R
  • May be used as a topical application on smooth or granule APP products for roofing repairs only
  • For repairing splits, breaks and small holes in asphalt based roof membranes and flashings
  • For applying SBS modified bitumen membrane flashing to parapet walls, curbs and roof penetrations
  • For sealing laps seams and perimeter edges of SBS modified bitumen membranes
  • For installing metal edge flanges and other metal joints
  • Positive-side damp proofing of concrete, masonry walls and foundations
  • DO NOT USE with PVC, TPO, EPDM or other single-ply membranes
  • DO NOT USE over or under expanded polystyrene insulation
  • Meets Miami-Dade-County Standards
  • Meets ICC-ES Standards

Documents

PDS 421 Mod Bit Adhesive - Trowel Grade
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SDS 421 Mod Bit Adhesive Trowel Grade
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Florida Product Approval - Cements, Adhesives, Coatings
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Miami-Dade NOA - Asphalt Products NOA
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Asphalt Cements & Coatings Cross Reference Chart
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Maintenance & Repair Brochure
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Mod Bit Pocket Guide
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Mod Bit Pocket Guide (Spanish)
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OTC Regulation Update for Adhesives and Sealants
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Self-Adhering Mod Bit - Membranes & Accessories
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Sell Sheet - 421 Mod Bit Adhesive - Trowel Grade
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Single-Ply Roofing Accessories Guide
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Tech Bulletin - Cold Weather Installation
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Details

INSIDE CORNER FOR MODBIT
OUTSIDE CORNER FOR MODBIT

BASE FLASHING - AREA DIVIDER MODBIT OPTION 1
BASE FLASHING - AREA DIVIDER MODBIT OPTION 2
BASE FLASHING - AREA DIVIDER MODBIT OPTION 3
BASE FLASHING - AREA DIVIDER OPTION 3
BASE FLASHING - MODBIT OPTION 1
BASE FLASHING - MODBIT OPTION 9
BASE FLASHING - OPTION 1
BASE FLASHING - OPTION 10
BASE FLASHING - OPTION 2
BASE FLASHING - OPTION 3
BASE FLASHING - OPTION 4
BASE FLASHING - OPTION 5
BASE FLASHING - OPTION 6
BASE FLASHING - OPTION 7
BASE FLASHING - OPTION 8
BASE FLASHING - OPTION 9
BASE FLASHING W/CANT - MODBIT OPTION 1
BASE FLASHING W/CANT - MODBIT OPTION 2
BASE FLASHING W/CANT - MODBIT OPTION 3
BASE FLASHING W/CANT - MODBIT OPTION 4
BASE FLASHING W/CANT - OPTION 1
BASE FLASHING W/CANT - OPTION 2
BASE FLASHING W/CANT - OPTION 3
BASE FLASHING W/CANT - OPTION 4
BASE FLASHING WITH MASTIC FOR MODBIT

DRAIN DETAIL - OPTION 1
FLANGED GUTTER WITHOUT DRIP EDGE
GUTTER DETAIL - MOD BIT OPTION 1
GUTTER DETAIL -MOD BIT OPTION 2
GUTTER WITH DRIP EDGE FOR MOD BIT
GUTTER WITH DRIP EDGE FOR MOD BIT - OPTION 2
RETROFIT DRAIN INSERT
RETROFIT DRAIN INSERT FOR MOD BIT - OPTION 2
ROOF DRAIN FOR MOD BIT

EXPANSION JOINT - SELF ADHERED

HOT STACK WITH MOD BIT
LIGHTNING ROD FOR MOD BIT
PENETRATION POCKET FOR MOD BIT - OPTION 1
PENETRATION POCKET FOR MOD BIT - OPTION 2
PIPE FLASHING MOD BIT - OPTION 2
PIPE FLASHING MOD BIT - OPTION 3
PIPE FLASHING MOD BIT - OPTION 4
PIPE FLASHING MOD BIT - OPTION 5
PIPE FLASHING MOD BIT - OPTION 1
VENT PIPE FOR MOD BIT

DRIP EDGE - MOD BIT OPTION 2
EDGE METAL FLASHING - MOD BIT OPTION 1
EDGE METAL FLASHING - MOD BIT OPTION 2
EDGE METAL FLASHING - MOD BIT OPTION 3
EDGE METAL FLASHING - MOD BIT OPTION 4
GRAVEL STOP - MODBIT OPTION 1
GRAVEL STOP - MODBIT OPTION 2
GRAVEL STOP - MODBIT OPTION 3

CUT CAP SHEET END LAPS - 45 DEGREE CUT

WALL FLASHING TERMINATION FOR MODBIT - OPTION 1
WALL FLASHING TERMINATION FOR MODBIT - OPTION 2
WALL FLASHING TERMINATION FOR MODBIT - OPTION 3
WALL FLASHING TERMINATION FOR MODBIT - OPTION 4
WALL FLASHING TERMINATION FOR MODBIT - OPTION 5

EPDM TIE-IN HOT STRIPPING
TIE-IN TO EXISTING SMOOTH MODBIT WITH TEAR-OFF

Options

Item ID Description Packaging Qty per Ctn Weight per Ctn Cover Rate
16MH4213 MH 421 MOD BIT ADHESIVE-TROWEL 3 GAL Metal Pail 1 26 8 gallons per 100 sq. ft. for 1/8"
16MH4215 MH 421 MOD BIT ADHESIVE-TROWEL 5 GAL Metal Pail 1 43 8 gallons per 100 sq. ft. for 1/8"

Videos

FAQs

The coverage rate for Mule-Hide #421 Mod Bit Adhesive – Trowel Grade is approximately 1 to 1.5 gallons per 100 sq. ft. when applied to a smooth surface. (All values are approximate and may vary with ambient temperature and job conditions.)

Mule-Hide #421 Mod Bit Adhesive – Trowel Grade can be applied using a trowel.

NO. DO NOT use Mule-Hide #421 Mod Bit Adhesive – Trowel Grade with PVC, TPO, EPDM or other single-ply roofing membranes.

Yes. DO NOT use Mule-Hide #421 Mod Bit Adhesive – Trowel Grade in the following applications: • Over or under expanded polystyrene insulation. • With organic saturated felts

With proper storage, the shelf life of Mule-Hide #421 Mod Bit Adhesive – Trowel Grade is 18 months from the date of manufacture.

Mule-Hide #421 Mod Bit Adhesive – Trowel Grade should be stored at a temperature of at least 45°F but not above 120°F. It should be stored at room temperature for at least 24 hours prior to use.

Mule-Hide #421 Mod Bit Adhesive – Trowel Grade should only be applied when the ambient temperature is at least 45°F and rising. Cold weather can result in uneven application and improper curing, and it will cause the product to stiffen, making application more difficult. Application is not recommended if the substrate temperature is above 140°F.