Del-Val 211 Flashing Cement - 5 Gallon Pail

Great Single-Ply Repair Product!


Modified Liquid Rubber Mastic

A waterproof Roof Repair Lifesaver in a Pail! Offers Great Adhesion to TPO & EPDM!


Armour Proof AP-2100 Modified Liquid Rubber Mastic is a single-component mastic, providing a waterproof, weather resistant membrane with excellent permeability and UV protection. Armour Proof AP-2100 Modified Liquid Rubber Mastic offers good elongation tensile strength properties, resisting lateral movement and allowing for expansion and contraction. This mastic is used for many different applications, including seams, fasteners, gutters, vent pipe penetrations, curbs and expansion joints. Use as part of a system with Armour Proof AP-6100 Modified Liquid Rubber

A Cool Roof Rated Roof Coating, that Offers a Durable Layer of Seamless, Flexible Protection

Where to Use AP-2100 Modified Liquid Rubber Mastic

Available Colors


Quick Application Guide

Coverage Rate


Average linear feet per gallon

Dry Time

1–6 HRS


Cure Time

48 HRS


Coverage & Drying Time

Apply AP-2100 by brush or trowel at a rate of 80 linear feet per gallon, according to the substrate and condition. Apply in two applications when embedding fabric reinforcement. Dry time is 1-6 hours. Cure time is 48 hours.


Apply AP-2100 by brush or trowel. Embed polyester reinforcement into the wet product and smooth out free of all wrinkles and fishmouths. Roof coating may be applied after one-two hours of application.

Preparation of Substrate

Surface must be pressure washed clean, free of all loose particles, dirt, debris and other contaminants that could inhibit adhesion. Refer to the Armour Proof Coatings Specification for detailed instructions on how to prepare the specific substrate.

Limitations and Precautions

AP-2100 contains VM&P Naphtha and Xylene. KEEP AWAY FROM HEAT, OPEN FLAMES OR SPARKS. USE ONLY IN WELL VENTILATED AREAS WITH PROPER PROTECTIVE EQUIPMENT. Approved (MESA/NIOSH) chemical respirator and protective clothing must be worn by applicator and other personnel in the vicinity of the application. Provide mechanical exhaust ventilation in enclosed areas. Positive pressure fresh air hose masks are required for interior applications.

Use as Part of a System with:

AP-6100 Modified Liquid Rubber Roof Coating 2024 Rebrand in 5 Gallon Pail


Modified Liquid Rubber

Product Information

Sizes Available

3 Gallon Capacity Pail

Tools Needed

Brush Tool Graphic
Trowel Tool Graphic


Available From These Distributors

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ABC Supply Co Distributor Logo
Beacon Roofing Supply Distributor Logo
J & L Building Materials Inc. Distributor Logo
New Castle Building Products Distributor Logo
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Universal Supply Co Distributor Logo
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