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York Seal 40-Mil Self-Adhering Flashing – 75' Rolls

SKU YS12
by York
Original price $139.62 - Original price $209.45
Original price
$209.45
$139.62 - $209.45
Current price $209.45
225.0ft | $0.93 / ft

Ships in 3–5 business days

York-Seal is a 40-mil self-adhering composite flashing membrane designed to limit air, moisture, vapor, and water transmission through masonry walls and building-envelope transitions. It combines a proprietary modified-asphalt adhesive with a durable, cross-laminated high-density polyethylene facer.

The membrane provides strong adhesion, low-temperature flexibility, and resistance to tearing and physical damage. York-Seal is fully bonded to the substrate and can be used for through-wall flashing, construction joints, and window and door transitions.

Key Features

  • 40-mil self-adhering composite membrane
  • Waterproof and impermeable to moisture
  • Limits air, vapor, and water transmission
  • Fully bonded to the substrate
  • Cross-laminated polyethylene facer provides tear resistance
  • Strong low-temperature adhesion and flexibility
  • High-temperature stability
  • Siliconized release liner for application
  • Suitable for through-wall flashing
  • Sold in full-box quantities only

Common Applications

  • Through-wall flashing
  • Masonry walls
  • Construction joints
  • Window and door flashing
  • Air-barrier transitions
  • End dams and flashing terminations

Compatible Substrates

  • Plywood
  • Lumber
  • Precast concrete
  • Concrete
  • Concrete block
  • Metal
  • Exterior gypsum sheathing
  • Brick and masonry with flush mortar joints

Material Construction

  • Total Thickness: 40 mil (1.0 mm)
  • Facer: Cross-laminated high-density polyethylene film
  • Adhesive: Proprietary modified asphalt
  • Release Liner: Siliconized release liner

Available Sizes and Packaging

  • 12" × 75' Roll - 3 rolls or 225' per box
  • 18" × 75' Roll - 2 rolls or 150' per box
  • 24" × 75' Roll - 1 roll or 75' per box

This product is sold in full-box quantities only.

Technical Performance

  • Tensile Strength: 1,200 psi minimum per ASTM D412
  • Elongation at Break: 200% per ASTM D412
  • Low-Temperature Pliability: Passes ASTM D146 at -25°F over a 1" mandrel
  • Peel Adhesion to Dry Concrete: 6 lb/in width per ASTM D903
  • Puncture Resistance: 50 lb per ASTM E154
  • Permeance: 0.05 perm maximum per ASTM E96B
  • Water Absorption: 0.1% by weight maximum per ASTM D570
  • Maximum UV Exposure: 60 days
  • Maximum Service Temperature: 180°F

Installation Requirements

  • Install when the air and surface temperatures are above 40°F.
  • Concrete must cure for a minimum of seven days and be completely dry.
  • Surfaces must be clean, dry, smooth, and free of voids, contaminants, and sharp protrusions.
  • Brick and block mortar joints must be struck flush.
  • Prime substrates before applying the membrane.
  • Roll the installed membrane firmly with a hard roller to remove wrinkles and air pockets.
  • Overlap adjoining pieces by 2" and seal the edge with an approved mastic.
  • Apply an approved sealant to termination edges, laps, cuts, and penetrations.
  • A surface-mounted termination bar is recommended for vertical terminations.
  • End dams require a minimum 2" membrane turn-up.

Limitations

  • Do not install over damp surfaces or substrates that have absorbed water.
  • Do not span gaps measuring 1/4" or greater.
  • Do not expose the membrane to temperatures above 180°F.
  • Do not use with sealants containing coal tar or polysulfides.
  • Avoid contact with products containing high levels of plasticizers.
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FAQ

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Do you offer free freight?

Yes, we offer free freight on orders over $2,500.

How long does shipping take?

Most orders ship and deliver within 4-8 business day.

Can I order in bulk or wholesale quantities?

Yes. We specialize in bulk and wholesale orders. Use our Wholesale Order form or request a quote.

Can you help me choose the right product?

Yes. Our team can review specs and recommend the correct product for your project.

Who do I contact with questions?

Call (833) 246-3900 or email sales@masonrydirect.com.