Quick Overview 

BlockFlashing Banner No Window webBlockShield SA Plus is made from proprietary high strength polypropylene sheet with a very aggressive adhesive layer that effectively bonds to virtually all deck types. For use on both commercial and residential construction, BlockShield SA Plus creates a barrier against vapor and air infiltration.

A self-adhered air, water, and vapor barrier roofing underlayment

  • Non-asphaltic air and vapor barrier roofing underlayment
  • Impermeable to air, moisture vapor, and water
  • Used on low slope roofs (¼”: 12”, <2”:12) and steep slope roofs( >2”:12)
  • Apply directly to galvanized or painted steel Type B deck
  • Apply to thermal board fastened to galvanized steel deck
  • Compatible with: OSB, plywood, and gypsum
  • 6 month UV and weather exposure
  • Application temperature 20°F (-6°C)
  • Tough, durable, and slip resistant
  • Zero VOCs
  • Compatible with many building sealants 
  • Class A UL Fire Rating, UL790 and CAN/ULC-S107 using a ¼” thermal board
  • 20 year material warranty


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Low Slope Applications (1/4":12", <2":12")

As a roofing underlayment, the product functions as a vapor and air barrier. BlockShield SA Plus is typically installed on the warm side, below rigid foam insulation in a compact insulated roof deck.

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Vented Attic Steep Slope (>2”:12”) Application

BlockShield SA Plus vapor and air barrier may be used in steep slope vented roof decks and vented attic assemblies. BlockShield SA Plus features 180 days exposure, walkability, traction, and nail sealability. The aggressive adhesive offers extreme adhesion to plywood, OSB, and gypsum substrates.

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