MB Plus Coating

Why TOPCOAT® MB Plus Coating?

TOPCOAT® MB Plus Membrane is a water-based, low-VOC, acrylic, sprayable polymeric liquid that cures to form a seamless rubber membrane. It covers and protects most roof surfaces including modified bitumen (smooth and granulated), smooth BUR, and metal.


  • ENERGY STAR® certified (U.S. only) reflectivity can dramatically decrease building temperatures
  • Highly reflective and listed by the Cool Roof Rating Council for solar reflectance and thermal emittance
  • Low VOC, non-flammable, and presents minimal hazard to the applicator or the environment
  • Easier to apply than solvent-based systems for asphalt surfaces
  • Limited warranty available for up to five years1
  • Guarantees available for up to 10 years2


  • TOPCOAT® MB Plus Membrane is designed to protect and restore aged roofs.
  • This product can be used on modified bitumen, BUR, Hypalon®, metal as a primer, wood, and concrete.
  • For use with water-based sealants and top coats only. 
  • Substrate shall not pond water for a period longer than 48 hours. Surface must be free of ponding water, ice, snow, and debris prior to application.
  • Do not apply at temperatures below 42°F. Substrate temperatures must be below 120°F when applying product. (for application questions, please contact GAF at 1-800-766-341).

1See applicable warranty or guarantee for complete coverage and restrictions.
2When used as a part of a multi-ply system.

Note: Repair leaks promptly to avoid adverse effects, including mold growth. Hyphalon® is a registered trademark of DuPont Performance Elastomeric LLC.


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