Self-adhered flexible flashing

Product Description

ROOF DETAIL MEMBRANE is a premier membrane based on the GRACE ICE & WATER SHIELD® roofing underlayment technology. The new membrane has the RIPCORD® split-release on demand feature placed in the center and near the edge (18 in. width) for easy installation at the transition areas as well as allowing for future tie-ins. The membrane also features square edge cuts and measure markings on the face to further simplify layout and installation. The membrane is composed of two waterproofing materials—an aggressive rubberized asphalt adhesive backed by a layer of high-density, cross-laminated polyethylene. The rubberized asphalt surface is backed with a release paper that protects its adhesive quality. During application, the release paper is easily removed, allowing the rubberized asphalt to bond tightly to the roof deck and walls.

The membrane is available in 9 in. and 18 in. widths. See the Product Data chart for more information.

Premium Protection at Roof Detail Areas

Roof details, such as valleys, rake edges, chimneys, ridges, skylights and dormer walls, can greatly enhance the beauty of any home. Unfortunately, they are also some of the most leak-prone areas on a roof.

The results can range from stained walls and ceilings to severe water damage, costing thousands of dollars to repair. Unless the leakage problem is corrected, damage will continue to result.

Granular underlayments may lack the ability to conform to many common roof details, creating the potential for leaks.

ROOF DETAIL MEMBRANE is a flexible product that conforms tightly to these transition areas, reducing the risk of water infiltration. ROOF DETAIL MEMBRANE is the only product available today designed specifically for waterproofing critical roof detail areas.

Product Advantages

  • Easy to handle and apply
  • Seals around nails
  • Membrane will not crack, dry out or rot
  • Protects under all standard sloped roof coverings
  • Slip resistant surface
  • Proven track record
  • Reroofable
  • Inhibits corrosion
  • Technical support

Features & Benefits

  • Easy to handle and apply—The self-adhesive membrane bonds firmly to the substrate without heat or special adhesives. Water cannot seep under the membrane. Watertight seams are easily formed. RIPCORD® split-release on demand is a unique, patented feature that makes ROOF DETAIL MEMBRANE easy to apply by giving the applicator a split release on demand. The split release makes positioning in detail areas easy by minimizing the amount of adhesive exposed during installation. Both the 9 in. and 18 in. rolls contain RIPCORD® split-release on demand placed at the center and near the edges to simplify application of the membrane at angled transitions, allowing the applicator to select the amount of adhesive to be exposed during installation.
  • Seals around nails—The rubberized asphalt layer in ROOF DETAIL MEMBRANE seals around roofing nails, resisting leakage caused by water back-up behind ice dams, or from wind-driven rain.
  • Membrane will not crack, dry out or rot—ROOF DETAIL MEMBRANE resists attacks from fungus and bacteria; maintains its integrity for long lasting protection.
  • Protects under all standard sloped roof coverings— ROOF DETAIL MEMBRANE protects under slate, tile, cedar shakes or metal, as well as under conventional asphalt shingles.
  • Slip resistant surface—ROOF DETAIL MEMBRANE has a slip resistant embossed surface to maximize traction and safety for applicators.
  • Proven track record—ROOF DETAIL MEMBRANE is based on GRACE ICE & WATER SHIELD® underlayment, the name brand in roofing underlayments with over 30 years of protecting roofs from ice dams and wind-driven rain.
  • Reroofable—Unlike some granular-surfaced membranes, ROOF DETAIL MEMBRANE will not adhere to the underside of the exposed roof covering. ROOF DETAIL MEMBRANE can be applied over the old underlayment (except over GCP granular underlayment) in retrofit applications, making reroofing easier, less costly—since there is no need for removing the existing underlayment—more durable and environmentally friendly—as the substrate remains intact, avoiding the need to purchase additional wood substrate.
  • Inhibits corrosion—ROOF DETAIL MEMBRANE isolates metal roof components from new corrosive wood preservatives.
  • Technical support—ROOF DETAIL MEMBRANE is backed by a team of technical support personnel that help ensure every application goes smoothly.

Guidelines for Use

ROOF DETAIL MEMBRANE is used as a flashing to provide resistance against water infiltration at trouble-prone roof detail areas such as valleys, drip edges, rake edges, chimneys, ridges, skylights, dormer walls and roof-to-wall transitions. Local building codes should be consulted for specific requirements.

Installation Procedure

Surface Preparation

Install ROOF DETAIL MEMBRANE directly on a clean, dry, continuous structural substrate. Some suitable substrates are plywood, wood composition, metal, concrete or gypsum sheathing. For all other substrates, contact your GCP representative. Remove dust, dirt, loose nails and old roofing materials. Protrusions from the substrate area must be removed. Substrates shall have no damaged or unsupported areas, or voids. Repair substrate before installing the membrane.


Prime concrete, masonry, DensGlass Gold® and DensDeck® surfaces with PERM-A-BARRIER® WB PRIMER. Prime wood composition and gypsum sheathing with PERM-A-BARRIER® WB PRIMER if adhesion is found to be marginal (refer to Technical Letter 12, Use on Oriented Strand Board (OSB) Roof Sheathing). Apply PERM-A-BARRIER® WB PRIMER at a rate of 250–350 ft2/gal (6–8 m2/L). Priming is not required for other suitable surfaces provided that they are clean and dry.

ROOF DETAIL MEMBRANE Installation with RIPCORD® Split Release Feature

Apply ROOF DETAIL MEMBRANE only in fair weather when the air, substrate and membrane are at temperatures of 40°F (5°C) or higher. Apply roof and wall covering at membrane temperatures of 40°F (5°C). Use ROOF DETAIL MEMBRANE on all critical areas or higher.

  1. Cut membrane to length.
  2. Locate and pull RIPCORD® line,splitting release liner. Place membrane in position.
  3. Remove half of the release liner, exposing part of the membrane.
  4. Press the exposed portion of the membrane into place with heavy hand pressure, smoothing outward toward the edge.
  5. Remove remaining portion of the release liner and press remaining membrane into place, using the same procedure. The remaining portion of release liner may be left in place to allow for future tie-ins. Refer to the GRACE ICE & WATER SHIELD® roofing underlayment Contractor’s Guide for specific detail drawings.

Consistent with good roofing practice, install the membrane such that all laps shed water. Always work from the low point to the high point of the roof.

Precaution & Limitations

  • Slippery when wet or covered by frost.
  • Consistent with good roofing practice, always wear fall protection when working on a roof deck.
  • Release liners are slippery. Remove from work area immediately after membrane application.
  • Do not leave permanently exposed to sunlight. Cover within 30 days.
  • Do not fold over the roof edge unless the edge is protected by a drip edge, gutter or other flashing material.
  • Do not install on chamfered edges of wood plank.
  • When lapping over granular, allow for 6 in. overlap and apply bead of roofing mastic along the edge of the ROOF DETAIL MEMBRANE.
  • Repair holes, fishmouths, tears and damage with a round patch of membrane, extending past the damaged area 6 in. (150 mm) in all directions. Seals around nails or fasteners. Fully adheres to decks, resisting leaks from wind-driven rain or water backup due to ice dams. Roof shingles ROOF DETAIL MEMBRANE Rubberized asphalt seals around nail Total adhesion to wood deck If fasteners are removed leaving holes in the membrane, it must be patched. The membrane may not self-seal open fastener penetrations.
  • Do not install fasteners through the membrane over unsupported membrane areas of the structural deck, such as over the joints between adjacent structural panels.
  • Due to its slight asphaltic odor, do not apply where membrane is exposed to interior living spaces. Refer to product literature for more complete information.
  • Not compatible with EPDM or TPO; use GRACE ULTRA™ roofing underlayment for tie-ins (refer to Technical Letter 5, Chemical Compatibility).
  • Not compatible with polysulfides, uncured neoprene, wood substrates with high concentrations of resin (pitch), or flexible PVC. ROOF DETAIL MEMBRANE is generally compatible with window and skylight flanges; for more information, refer to Technical Letter 5.
  • Do not use in the desert southwest U.S.
  • Do not use under copper, COR-TEN® or zinc metal roofs in high altitudes.
  • A minimum of 36 in. is recommended at the eaves, where ice dams may form. GCP recommends GRACE ICE & WATER SHIELD® roofing underlayment for this application. ROOF DETAIL MEMBRANE may be used in conjunction with a self-adhered underlayment to extend ice dam protection at the eaves.
Product Data 18 in. width 9 in. width
Roll length 50 ft (15.2 m) 50 ft (15.2 m)
Roll width 18 in. (457 mm) 9 in. (229 mm)
Roll size 75 ft2 (7.0 m2) 37.5 ft2 (3.5 m2)
Ripcord One at center (9 in. from edge)
Two near edge (4.5 in. from edge)
One at center (4.5 in. from edge)
Packaging Corrugated carton Six individually labeled rolls in corrugated carton
Roll weight 19 lbs (8.6 kg) 9.5 lbs (4.3 kg)
Rolls per carton One (1) Six (6)
Cartons per pallet 50 30

Code Compliance

ROOF DETAIL MEMBRANE meets the following standards:

  • Underwriters Laboratories Inc. Class A fire classification under fiber-glass shingles and Class C under organic felt shingles (per ASTM E108/UL 790)
  • International Conference of Building Officials (ICBO-ES) Report No. 3997
  • Southern Building Code Congress International (SBCCI PST & ESI) Report No. 94133C
  • Building Officials and Code Administrators (BOCA-ES) Evaluation Report No. 94-33
  • Miami-Dade County NOA 09-0107.08.
  • City of Los Angeles RR 25330

Performance Properties

Color Gray-black  
Thickness, membrane 40 mil (1.02 mm) ASTM D3767 method A
Tensile strength, membrane 250 psi (1720 kN/m2) ASTM D412 (Die C modified)
Elongation, membrane 250% ASTM D412 (Die C modified)
Low temperature flexibility Unaffected @ -20°F (-29°C) ASTM D1970
Adhesion to plywood 3.0 lbs/in. width (525 N/m) ASTM D903
Permeance (max) 0.05 Perms (2.9 ng/m2s Pa) ASTM E96
Material weight installed (max) 0.3 lb/ft2 (1.3 kg/m2) ASTM D461 | North America Customer Service: +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.

GRACE ICE & WATER, GRACE ULTRA, GCP granular underlayment, PERM-A-BARRIER, and RIPCORD are trademarks, which may be registered in the United States and/or other countries, of GCP Applied Technologies Inc. COR-TEN is a trademark registered in the United States and/or other countries, of United States Steel Corporation. DensGlass Gold and DensDeck are registered trademark of Georgia-Pacific Corporation. 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 475, 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 United States. 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: 2024-06-21