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 air, water, and vapor infiltration.

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

  • Non-asphaltic air and vapor barrier roofing underlayment
  • No Red List Chemicals
  • Contains 18-20% post-industrial recycled content
  • Impermeable to air, moisture vapor, and water
  • For use on roofs with a minimum slope of ¼”: 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
  • Apply directly to structural concrete, see installation instructions
  • Does not require primer
  • 6 month UV and weather exposure
  • Application temperature 20°F (-6.6°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

BlockFlashing Icons SidebySide 01

Low Slope Applications

BlockShield SA Plus is typically installed on the warm side, below rigid foam insulation in a compact insulated roof deck.

BlockShield SA Plus Installed Directly to Steel Deck


BlockShield SA Plus Installed on Thermal Board

LowSlope WebImages 02a

BlockShield SA Plus Head Lap over Metal Deck

LowSlope WebImages 03a

Structural Concrete* Roof Decks

LowSlope WebImages 04

Vented Attic Steep Slope

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.

SteepSlope Web Image 012324

BlockShield SA Plus Wheelbarrow Test

BlockShield SA Plus for Roofs Wheelbarrow test

BlockShield SA Plus directly applied to steel roof deck after the Wheelbarrow Test.

Compatible Substrates

  • Gypsum/Fiber Roof Sheathing Boards
  • Concrete (bull float finish or better)
  • Plywood
  •  Pre-painted Steel
  • Galvanized Metal
  • Steel Deck
  • Aluminum (Painted/Mill Finish)


 NEMOCert BlockShield Logo  UL Black Logo Horizontal




Related Products