SMARTCOAT™ 420 Fibered Aluminum Coating is a heavy-duty fibered aluminum coating that provides maximum reflectivity while giving unsurpassed protection against moisture and corrosion. Our unique formulation forms a heavy and brilliant silvery finish that preserves, prevents rust, inhibits fungus, and reflects over 70 percent of the sun’s damaging rays, while reducing interior temperatures. Our use of paint-grade aluminum pigment (as opposed to the coarser, less leafing “roofing” grade) gives a much finer leafing effect and a vastly superior coating to other brands. Our use of naturally occurring bituminous resins fortifies the asphalt with unparalleled strength to give it greater resistance to the damaging effects of the elements. SMARTCOAT 420 Fibered Aluminum Coating meets or exceeds all the requirements of ASTM D 2824-06 Type III and Federal Specification TTC 1079.

Technical Information



Dry to Touch

1-2 hours




44 lbs.


500 g/L


Semi Mastic


7.8 ± 3 lbs./G

Flash Point (T.C.C.)



Coverage: 1 – 1.5 gallons per 100 square feet. 

Precautions: This coating is not recommended over PVC sheet roofing, rubber, gravel, shingles of any kind, or old roofs that are too dry and brittle. Applying SMARTCOAT 420 directly over hot-applied asphalt can result in alligatoring. Apply according to ASTM D3805. When applying over new modified bitumen roof membranes, allow a minimum of 30 days after installation before coating. 

1. Clean roof surface thoroughly with SMARTCOAT 100 Roof Wash.  Surface must be free any contamination that may inhibit adhesion.  Surface must be clean and dry, free of moisture both on and beneath the surface before coating. 

2. Seal/repair roof as needed with reinforcing fabric and CertainTeed FlintPatch® prior to coating.  Allow FlintPatch or any solvent-based repair to cure a minimum of 30 days prior to coating with SMARTCOAT 420. 

3. Mechanically mix COATING before using. Stir thoroughly before and during application.  Recommended to apply at temperatures between 50ºF and 110ºF rising and no threat of rain for 24 hours. Apply on warm, sunny days, preferably in the morning hours to provide maximum cure time. 

4. Apply with a soft-bristle brush, paint roller, or heavy-duty spray equipment at stated coverage rate.  Avoid over-application.  Do not work coating excessively during application. Attempt to brush or roll on in one direction.  

5. Clean tools with mineral spirits or paint thinner.

For Construction Details and Specs Click Here


Warranty Details

CertainTeed offers three asphaltic low-slope roof system warranty options: Limited Warranty on Materials, Integrity Roof System Limited Warranty, and Integrity Roof System No Dollar Limit (NDL) Limited Warranty. CertainTeed warranty durations are based on a combination of system specification and product selection. Please download an overview of these warranty options for details. Consult with your contractor or CertainTeed Territory Manager to determine which warranty is best for your project.     

CertainTeed offers standard asphaltic low-slope roof system warranty durations between ten and twenty-five years. Additionally, Gold Star Contractors can increase warranty durations by 25% by engaging in an Integrity Maintenance Agreement with their client.

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