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121 Asphalt Primer

121 Asphalt Primer

A general-purpose penetrating asphalt primer used to promote adhesion prior to the application of hot-mopped, cold-applied and self-adhesive membrane systems, as well as roof cements, mastics and asphalt-based adhesives.

System

ModBit
M&R
  • Designed to be used on smooth surfaced built-up roofs, polymer-modified (APP, SBS) bituminous membranes, and roll-roofing membranes as a protective coating
  • DO NOT USE with PVC, TPO, EPDM or other single-ply membranes
  • Can be used as a protective surface for metal roofing, masonry, stucco, parapet walls, curbs and base flashings
  • Meets Miami-Dade-County Standards
  • Meets ICC-ES Standards

Documents

PDS 121 Asphalt Primer - Pail and Aerosol
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SDS 121 Asphalt Primer - Aerosol
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SDS 121 Asphalt Primer - Pail
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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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OTC Regulation Update for Adhesives and Sealants
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Sell Sheet - 121 Asphalt Primer
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Single-Ply Roofing Accessories Guide
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Details

INSIDE CORNER FOR MODBIT
INSIDE CORNER ISOMETRIC FOR MODBIT
OUTSIDE CORNER FOR MODBIT
OUTSIDE CORNER ISOMETRIC FOR MODBIT
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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 COMBUSTIBLE SUBSTRATE FOR MODBIT
BASE FLASHING FOR VENTED PERIMETER FOR MODBIT
BASE FLASHING NONCOMBUSTIBLE SUBSTRATE
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
BASE FLASHING WITH METAL COUNTERFLASHING FOR MODBIT
HIGH WALL PARAPET FLASHING FOR MODBIT
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HVAC WOOD CURB FOR MODBIT
PARAPET WALL WITH METAL COPING FOR MODBIT
PREFABRICATED METAL CURB 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 1
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

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

TIE-IN TO EXISTING SMOOTH MODBIT WITH TEAR-OFF

Options

Item ID Description Packaging Qty per Ctn Weight per Ctn Cover Rate
16MH12114 MH 121 ASPHALT SPRAY PRIMER 14 oz 30/CT Spray Can 30 37 30 sq. ft. per can
16MH1215 MH 121 ASPHALT PRIMER 5 GAL Metal Pail 1 41 1 gallon per 100 sq. ft.
16MH12150 MH 121 ASPHALT PRIMER 50 GAL Drum 1 408

Videos

FAQs

Mule-Hide #121 is a solvent-based bond coat and penetrating sealer for priming most surfaces prior to application of cold applied or hot mopped asphalt coatings, roof cements, adhesives, asphalt damp proofing and waterproofing. Not recommended as a stand-alone roof coating.

Application range is between 0.5-1.0 gallons per 100 sq. ft. depending on surface porosity.

Apply a thin, single coat of#104 over the entire surface with a roller or heavy-duty spray equipment. Brush out any excess immediately after application. Avoid over-application and build-up of surface film. Allow to dry thoroughly before applying adhesives or coatings. Store primer in a warm room overnight before using in cold weather.

#121 Asphalt Primer dries in approximately 2-24 hours in warm, dry weather. Drying time varies with weather conditions.

No, DO NOT use #121 Asphalt Primer on PVC, TPO, EPDM or other single-ply membranes.

With proper storage, the shelf life of Mule-Hide #121 Asphalt Primer is 24 months from the date of manufacture, for bucket goods. Aerosol cans may leak propellant over time, leading to a shortened shelf life of only 12 months. Store primer in a warm room overnight before using in cold weather.

#121 Asphalt Primer 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.

#121 Asphalt Primer 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.