PERM-A-BARRIER® Aluminum Flashing

Self-adhesive, rubberized asphalt/polyethylene detail membrane for air and vapor barrier applications

Product Description

PERM-A-BARRIER® Aluminum Flashing is ideal for protecting and sealing critical areas of the building superstructure from the damaging effects of the elements. By minimizing air and water vapor flow through the building exterior at transition areas, PERM-A-BARRIER® Aluminum Flashing:

  • Seals transition and detail areas to provide a continuous air barrier
  • Prevents premature deterioration of the building envelope
Drawings are for illustration purposes only. Please refer to for specific application details.

Product Advantages

  • Fully bonded - transmits wind loads directly to the substrate
  • Waterproof and impermeable to moisture - impermeable to the passage of liquid water and water vapor
  • Aluminum faced film - provides extended UV exposure, improved sealant adhesion to film, dimensional stability, high tear strength, puncture and impact resistance
  • Cold applied - no flame hazard; self-adhesive overlaps ensure continuity
  • Flexible - accommodates minor settlement and shrinkage movement
  • Controlled thickness - factory made sheet ensures constant, non-variable site application
  • Aggressive, conformable adhesive - allows self-sealing around mechanical fasteners
  • Wide application window - PERM-A-BARRIER® Aluminum Flashing surface and ambient temperatures at 25°F (-4°C) and above

System Components

  • PERM-A-BARRIER® Aluminum Flashing - Aluminum faced fully adhered flashing for protecting and sealing critical detail areas
  • PERM-A-BARRIER® WB Primer - high tack, water-based primer for use with PERM-A-BARRIER® Aluminum Flashing on cementitious and exterior gypsum wallboards
  • BITUTHENE® Primer B2 LVC - low VOC solvent-based primer for green concrete or damp surfaces
  • PERM-A-BARRIER® Universal Flashing & Sealant - one part moisture curing, STPE sealant for sealing penetrations, terminations, brick ties, final terminations & flashing application.
  • BITUTHENE® Mastic Trowel Grade - rubberized asphalt mastic for sealing patches, terminations, brick ties, etc.
  • BITUTHENE® Liquid Membrane - two component, trowel grade, asphalt modified urethane for sealing patches, terminations, brick ties, etc.



PERM-A-BARRIER® products must be handled properly. Vapors from the mastic and solvent-based primer are harmful and flammable. For these products, the best available information on safe handling, storage, personal protection, health and environmental considerations has been gathered. Refer to product label and SDS (Safety Data Sheet) before use. All users should acquaint themselves with this information prior to working with the material. Carefully read detailed precaution statements on the product labels and SDS before use. SDSs can be obtained from our web site at or by contacting us toll free at 866-333-3SBM (3726). 

Surface Preparation

Surface must be smooth, clean, dry and free of voids, spalled areas, loose aggregate, loose nails, sharp protrusions or other matter that will hinder the adhesion or regularity of the wall membrane installation. Clean loose dust or dirt from the surface to which the detail membrane is to be applied by wiping with a clean, dry cloth or brush.

If the substrate is damp, allow to dry or use BITUTHENE® Primer B2 LVC to prepare the area to receive the membrane. DO NOT apply any primer to PERM-A-BARRIER® Aluminum Flashing.


PERM-A-BARRIER® Aluminum Flashing may only be applied in dry weather when air and surface temperatures are above 25°F (-4°C).


Priming - PERM-A-BARRIER® WB Primer is a water-based primer which imparts an aggressive, high tack finish on the treated substrate. They are packaged ready to use and are specifically designed to facilitate tenacious adhesion of PERM-A-BARRIER® Aluminum Flashing to various substrates including glass-mat faced gypsum sheathing. Refer to Technical Letter 2,Substrate Preparation for Application of PERM-A-BARRIER® Products to Glass-Mat Faced Gypsum Sheathing for priming requirements on specific glass-mat faced sheathing products.

Aluminum Flashing Application - Pre-cut PERM-A-BARRIER® Aluminum Flashing to easily handled lengths. Peel release paper from roll to expose rubberized asphalt and carefully position tape against substrate. Press firmly into place with a steel hand roller or the back of a utility knife as soon as possible, fully adhering the tape to the substrate to prevent water from migrating under the PERM-A-BARRIER® Aluminum Flashing. Overlap adjacent pieces 2 in. (51 mm) and roll overlap with a smooth seam roller.

When applying Aluminum Flashing to PERM-A-BARRIER® Wall Membranes and Wall Flashing - Apply a bead of Universal Flashing & Sealant, BITUTHENE® Mastic or BITUTHENE® Liquid Membrane along all top edges, cuts, penetrations and as shown in GCP detail drawings, and trowel into place.

When applying Aluminum Flashing to PERM-A-BARRIER® Liquid, PERM-A-BARRIER® VP, PERM-A-BARRIER® VP Low Temp or PERM-A-BARRIER® VPO - Apply a bead of Universal Flashing & Sealant or BITUTHENE® Liquid Membrane along all top edges, cuts, penetrations and as shown in detail drawings, and trowel into place. If PERM-A-BARRIER® Liquid is more than 7 days old, priming may be necessary. Refer to Technical Letter 11 for more information.

Complete installation instructions and details are available upon request.

If wrinkles develop, carefully cut out affected area and replace in similar procedure outlined above. The repair piece must be pressed into place with a hand roller as soon as possible to ensure continuous and intimate contact with the substrate.

All non water shedding edges must be sealed with Universal Flashing & Sealant, BITUTHENE® Liquid Membrane or BITUTHENE® Mastic.

Membrane Protection

PERM-A-BARRIER® Aluminum Flashing must be protected from damage by other trades or construction materials.

Storage and Handling Information

All materials must be protected from rain and physical damage. Pallets of PERM-A-BARRIER® Aluminum Flashing must not be double stacked on the job site. Provide cover on top and all sides, allowing for adequate ventilation. Store membrane where temperatures will not exceed 90°F (32°C) for extended periods. All products must be stored in a dry area away from high heat, flames or sparks. Store only as much material at point of use as is required for each day’s work.


PERM-A-BARRIER® Aluminum Flashing must not be applied in areas where it will be exposed to direct sunlight permanently, and must be covered within 1 year. Refer to Technical Letter 19, Exposure Guidelines for PERM-A-BARRIER® Self-Adhered Membranes.

PERM-A-BARRIER® Aluminum Flashing and all other PERM-A-BARRIER® self-adhered membranes should not be applied over Universal Flashing & Sealant.


PERM-A-BARRIER® products are warranted to be free of defects in manufacture for a period of 5 years. Material will be provided at no charge to replace any defective product.

Technical Service

Support is provided by full-time technically trained GCP field sales representatives and technical service personnel, backed by a central research and development technical services staff.

Physical Properties

Available in 4’’, 6’’, 9’’, 12’’ & 18’’ width

Property Typical Value Test Method
Thickness 0.040 in. (1.0 mm) ASTM D3767 method A
Minimum tensile strength, membranes 600 psi ASTM D412 die C modified
Minimum tensile strength, film 4000 psi ASTM D412 die C modified
Minimum elongation, to failure of rubberized asphalt 200% ASTM D412 die C modified
Pliability, at 180° bend over 1 in. (25 mm) mandrel Pass at -15°F (-26°C) ASTM D1970
Crack cycling, 1/8in. (3.2 mm) at -25°F (-32°C) Unaffected ASTM C836
Minimum puncture resistance, membrane 80 lbs (355 N) ASTM E154
Water absorption 0.1% ASTM D570 | North America customer service: 1-877-4AD-MIX (1-877-423-6491)

We hope the information here will be helpful. It is based on data and knowledge considered to be true and accurate, and is offered for consideration, investigation and verification by the user, but we do not warrant the results to be obtained. Please read all statements, recommendations, and suggestions in conjunction with our conditions of sale, which apply to all goods supplied by us. No statement, recommendation, or suggestion is intended for any use that would infringe any patent, copyright, or other third party right.

Bituthene and PERM-A-BARRIER® are trademark, which may be registered in the United States and/or other countries, of GCP Applied Technologies Inc. This trademark list has been compiled using available published information as of the publication date and may not accurately reflect current trademark ownership or status.

© Copyright 2018 GCP Applied Technologies Inc. All rights reserved.

GCP Applied Technologies Inc., 2325 Lakeview Parkway, Suite 450, Alpharetta, GA 30009, USA
GCP Canada, Inc., 294 Clements Road, West, Ajax, Ontario, Canada L1S 3C6.
This document is only current as of the last updated date stated below and is valid only for use in the Canada. It is important that you always refer to the currently available information at the URL below to provide the most current product information at the time of use. Additional literature such as Contractor Manuals, Technical Bulletins, Detail Drawings and detailing recommendations and other relevant documents are also available on Information found on other websites must not be relied upon, as they may not be up-to-date or applicable to the conditions in your location and we do not accept any responsibility for their content. If there are any conflicts or if you need more information, please contact GCP Customer Service.

Last Updated: 2023-07-14