Del-Val 211 Flashing Cement - 5 Gallon Pail

Make Wet Surface Repairs!


Silicone Mastic

A One-Part, High-Performance, Low VOC Mastic Great for Roof Repairs!


Armour Proof AP-2400 Silicone Mastic is a one-part, high solids, low VOC silicone elastomeric flashing mastic specifically designed for use in sealing roof penetrations, seams, curbs, flashings and other areas on the roof where water infiltration is possible. It works well on roofs that were previously coated with AP-5200 Silicone Coating. Once cured, this liquid applied silicone mastic provides a durable, seamless, flexible, waterproof membrane that resists lateral movement, shear and will allow for normal expansion and contraction.

specifically designed for use in sealing roof penetrations, seams, curbs, flashings and other areas on the roof where water infiltration is possible.

Where to Use AP-2400 Silicone Mastic

Quick Application Guide

Coverage Rate


Average linear feet per gallon

Dry Time To Touch



Tack Free Time

8–12 HRS


Application, Coverage & Drying Time

Brush apply AP-2400 at a rate of 100 linear feet over a seam at 4” wide. Minimum wet mil thickness shall be 40 mils. Normal drying time is 6 hours to touch, tack free in 8-12 hours.

Preparation of Substrate

Surface must be cleaned, 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

Shelf Life is 12 months stored indoors at 50 – 85°F. Avoid contamination in sealed containers. Store away from heat, sources of ignition and incompatibles. Use only in well ventilated areas. Refer to SDS for more information. Note: Silicone can be applied on many substrates, but many coatings will not stick on-top of silicone. Be sure to following your Armour Proof Coating Specification and/or Get in Touch with Your Local Rep.

Use as Part of a System with these products:

AP-5200 Silicone Roof Coating 2024 Rebrand in 5 Gallon Pail


Silicone Roof Coating

AP-5400 High Solids Silicone Roof Coating 2024 Rebrand in 5 Gallon Bucket


High Solids Silicone Roof Coating

Product Information

Sizes Available

2 Gallon Capacity Bucket

Tools Needed

Brush 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
Image of SRS Distribution's Logo
Universal Supply Co Distributor Logo
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