PREPRUFE® 300LT & 160LT Membranes Data Sheet

Pre-applied fully-bonded waterproofing membranes for low temperature applications

Product Description

GCP Applied Technologies (“GCP”) PREPRUFE® Low Temperature Membranes (300LT and 160LT) are proprietary composite sheets comprised of a thick HDPE film, pressure sensitive adhesive and weather resistant protective coating. Designed with Advanced Bond Technology™, PREPRUFE® 300LT & 160LT membranes form a proprietary, integral bond to poured concrete, designed to prevent lateral migration of water while providing a robust barrier to water, moisture and gas penetration.

Product Advantages

  • Forms a continuous adhesive bond to concrete poured against it specifcally designed to prevent water migration Continuous Direct bond to poured concrete means PREPRUFE® 300LT & 160LT membranes are unaffected by ground settlement 
  • Can be placed directly over properly prepared compacted soil 
  • Does not activate prematurely during construction 
  • Fully adhered watertight laps and detailing
  • Provides a barrier to water, moisture and gas - physically isolates the structure from the surrounding ground BBA Certified for all basement grades (BS 8102:2009)
  • Impermeable- Perm rating less than 0.1 Perms
  • Solar reflective - reduced temperature gain during construction
  • Can be applied to permanent formwork - maximizes use of confined sites Allows for foot traffic immediately after application
  • Ready for immediate placing of reinforcing steel 
  • Inherently waterproof--does not require water activation
  • Waterproofing is not reliant on confining pressures or hydration
  • Installed membrane is not affected by exposure to water during construction Waterproofing performance unaffected by wet/dry cycling
  • Chemical resistance – protects structure from salt and sulfate attack, effective in most types of soils and waters

System Components


  • PREPRUFE® 300LT membrane- heavy-duty 46-mil grade can be used in horizontal applications below slabs and on rafts (i.e. mud slabs) and can be applied to vertical (blind side) substrates. PREPRUFE® 300R LT membrane is designed to accept the placing of heavy reinforcement using conventional concrete spacers
  • PREPRUFE® 160LT membrane 32 mil grade for blindside, zero property line applications against soil retention systems. Vertical use only.

Ancillary Components (the most current Data Sheets for all system components are available on

  • PREPRUFE® Tape LT – Low temperature tape for covering cut edges, roll ends, penetrations and detailing in cold weather 
  • PREPRUFE® CJ Tape LT – Low temperature joint tape for construction joints and detailing in cold weather conditions 
  • BITUTHENE® Liquid Membrane - for sealing around penetrations, etc.
  • ADCOR® - waterstop for joints in concrete walls and floors
  • PREPRUFE® Tieback Covers - preformed cover for soil retention wall tieback heads 

Limitations of Use

  • Approved uses only include those uses specifically detailed in this Product Data Sheet and other current Product Data Sheets that can be found at
  • PREPRUFE® 300LT & 160LT membranes are not intended for any other use. Contact GCP Technical Services where any other use is anticipated or intended. 
  • PREPRUFE® 300LT & 160LT membranes are designed for in-service temperatures below 120°F (49°C)
  • PREPRUFE® 160LT membrane should not be used in horizontal applications
  • PREPRUFE® 300LT & 160LT membranes should not be used with conventional twin-sided formwork. (See PREPRUFE® Technical Letter # 13 Forming Systems For Use with PREPRUFE® Membranes)

Safety and Handling

Users must read and understand the product label and Safety Data Sheets for each of the system components 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. SDS’s can be obtained from our web site at or by contacting GCP toll free at 1-866-333-3SBM (3726).


  • Observe 1 year shelf life and use on a first in first out basis 
  • Store in dry conditions at 40°F (4.5°C)-90°F (32°C)
  • Store off ground under tarps or otherwise protected from rain and ground moisture
  • See PREPRUFE® Technical Letter #30 Shelf Life/Storage and Handling of GCP Waterproofing


Technical Support, Details and Technical Letters

The most up to date detail drawings and technical letters are available at For complete application instructions, please refer to the current GCP Applied Technologies Contractor Handbook and Literature on ( Documents in hardcopy as well as information found on websites other than may be out of date or in error. Before using this product it is important that information be confirmed by accessing and reviewing the most recent product information, including without limitation Product Data Sheets and Contractor Manuals, Technical Bulletins, Detail Drawings and detailing recommendations. Please review all materials prior to installation of PREPRUFE® 300LT & 160LT membranes. For technical assistance with detailing and problem solving please call toll-free at (866) 333-3SBM (3726).

Temperature Requirements

  • PREPRUFE® Low Temperature Membranes can be applied at temperatures between 25°F (-4°C) to 60°F (15.5°C).
  • As an alternative or if applying in conditions between 55°F (13°C) to 95°F (35°C), PREPRUFE® 300R and 160R can be used. Refer to the PREPRUFE® 300R and 160R data sheet for more information.
  • Refer to PREPRUFE® LT Membrane data sheet and Technical Letter #16 PREPRUFE® Waterproofing membranes: Cold Weather installation for more information.

Substrate Preparation

All surfaces - It is essential to create a sound and solid substrate to eliminate movement during the concrete pour. Substrates must be regular and smooth with no gaps or voids greater than 0.5 in. (12 mm). Grout around all penetrations such as utility conduits, etc. for stability.

Horizontal - The substrate must be free of loose aggregate and sharp protrusions. Avoid curved or rounded substrates. When installing over earth or crushed stone, ensure substrate is well compacted to avoid displacement of substrate due to traffic or concrete pour. The surface does not need to be dry, but standing water must be removed.

Vertical - Use concrete, plywood, insulation or other approved facing to sheet piling to provide support to the membrane. Board systems such as timber lagging must be close butted to provide support and not more than 0.5” (12mm) out of alignment. HYDRODUCT® 200 or 220 drainage sheets can be used to span voids, gaps and substrates out of alignment up to 2in. (50mm) prior to PREPRUFE® Membrane installation.

Membrane Application

PREPRUFE® 300LT & 160LT membranes are supplied in rolls 4 ft. (1.2m) wide, with a selvedge on one side to provide self-adhered laps for continuity between succeeding sheets. The rolls of PREPRUFE® Membrane and PREPRUFE® Tape are manufactured with a disposable plastic release liner, which must be removed before placing reinforcement and concrete. NOTE that the release liner must also be removed before application of any required tapes and at all surfaces where a bond between layers is to be formed.

Horizontal substrates – (PREPRUFE® 300LT only)
PREPRUFE® 300LT membrane can be applied horizontally to smooth prepared concrete or well rolled and compacted earth or crushed stone substrate. Place the PREPRUFE® 300LT membrane HDPE film side to the substrate with the clear plastic release liner facing towards the concrete pour. End laps should be staggered to avoid a buildup of layers. Leave plastic release liner in position until overlap procedure is completed. When completed remove release liner. When installing over carton forms, contact your local GCP representative.


  • PREPRUFE® 300LT membrane can be returned up the inside face of slab attain a fully bonded system and to allow a tie in with BITUTHENE® self-adhered membrane or PROCOR® fluid-applied membrane to all vertical structural surfaces after removal of formwork.
  • Rebar Chairs: See PREPRUFE® Technical Letter #15 Rebar Chairs on PREPRUFE® Membranes.
  • PREPRUFE® 160LT membrane should not be used in horizontal applications.

Vertical substrates –

PREPRUFE® 300LT & 160LT membranes can be applied vertically to permanent formwork or adjoining structures. Concrete should then be cast directly against the adhesive side of the membrane. The membrane may be installed in any convenient length. The clear plastic release liner must be facing towards the concrete pour. Membrane must be shingle overlapped a minimum of 3” (75mm). All laps over cut edges must be taped using PREPRUFE® Tape.

Vertically placed sheets can be held in place using fasteners appropriate to the substrate.  Fastening can also be made through the selvedge overlap area using a small and low profile head fastener so that the membrane lays flat and allows firmly rolled overlaps. Fasteners should be placed in the selvedge approximately 0.5”(12.5mm) from the leading edge of the membrane using a low profile head fastener so that the membrane lays flat over the fastener. . The adhesive selvedge of successive membrane sheets must completely cover any fasteners by a minimum of 1 in. (25mm). After rolling immediately remove the plastic release liner. When placing successive sheets insure the underside of each succeeding sheet is clean, dry and free from contamination before attempting to overlap. After placement roll the membrane firmly to ensure a watertight seal.
Note that PREPRUFE® 300LT & 160LT membranes are not recommended for use with conventional two-sided formwork. (See PREPRUFE®  Technical Letter # 13 Forming Systems For Use with PREPRUFE® Membranes)

Roll ends and cut edges –

Overlap all roll ends and cut edges by a minimum 3 in. (75 mm) and ensure the area is clean and free from contamination, wiping with a damp cloth if necessary. Allow the membrane to dry and apply PREPRUFE® Tape LT centered over the lap edges and roll firmly. Immediately remove plastic release liner from the tape.

Membrane Repair

Inspect the membrane before installation of reinforcement steel, formwork and final placement of concrete. The membrane can be easily cleaned by power washing if required. Repair damage by wiping the area with a damp cloth to ensure the area is clean and free from dust, and other contaminants and allow the membrane to dry. Repair small punctures and slices (0.5 in. (12 mm) or less by applying PREPRUFE® Tape LT centered over the damaged area. Repair punctures and holes larger than 0.5 in. (12mm) by applying a patch of PREPRUFE® Low Temperature Membrane. Extend the patch 6 in. (150 mm) beyond the damaged area. Seal all edges of the patch with PREPRUFE® Tape LT. Where exposed selvedge has lost adhesion or laps have not been sealed, ensure the area is clean and dry and cover with fresh PREPRUFE® Tape. LT Any areas of damaged adhesive should be covered with PREPRUFE® Tape LT. All PREPRUFE® Tape LT must be rolled firmly and the tinted release liner removed.

Slices or relief cuts can be butted or overlapped and repaired by applying PREPRUFE® Tape LT centered over the edge of the overlap or center of the butt joint. Where it is not possible to create a butt joint or overlap, repair with fresh membrane and PREPRUFE® Tape LT as detailed above.

Pouring of Concrete

IMPORTANT: Prior to pouring concrete, ensure the plastic release liner is completely removed from all areas of PREPRUFE® Low Temperature Membrane and PREPRUFE® Tape LT. The PREPRUFE® Membrane surface must be free of all contaminants, dirt and debris and all standing water prior to concrete placement. 

Under most climatic conditions concrete should be poured within 56 days of membrane installation.  Where ambient temperatures will exceed 38°C (100ºF) for more than a total of 7 days, concrete should be placed within 42 days of installation of the membrane. Concrete must be placed and compacted carefully to avoid damage to the Membrane. 

Following proper ACI guidelines, concrete must be placed carefully and consolidated properly to avoid damage to the membrane. Never use a sharp object to consolidate the concrete. Provide temporary protection from concrete over splash for areas of the PREPRUFE®  membranes that are adjacent to a concrete pour.

Removal of Formwork

A minimum concrete compressive strength of 3000 psi (20 N/mm2) is recommended prior to stripping formwork supporting PREPRUFE® membranes. Premature stripping may result in displacement of the membrane and/or spalling of the concrete. (see PREPRUFE® Technical Letter #17 Removal of Formwork Placed against PREPRUFE® membranes)

After removal of the formwork and prior to backfilling, all exposed PREPRUFE® Membrane must be protected from damage with an approved protective course


Dimensions (Nominal) PREPRUFE® 300LT Membrane PREPRUFE® 160LT Membrane
Roll size 4 ft x 98 ft (1.2 m x 30 m) 4 ft x 115 ft (1.2 m x 35 m)
Roll weight 108 lbs (49 kg) 92 lbs (42 kg)
Minimum side/end laps 3 in. (75 mm) 3 in. (75 mm)

Ancillary Products: The most current supply information for ancillary products can be found at 

Physical Properties

Property Typical Value PREPRUFE® 300LT Membrane Typical Value PREPRUFE® 160LT Membrane Test Method
Color white white  
Thickness 0.046 in. (1.2 mm) 0.032 in. (0.8 mm ASTM D3767
Lateral Water Migration Resistance Pass at 231 ft (71 m) of hydrostatic head pressure Pass at 231 ft (71 m) of hydrostatic head pressure ASTM D53851
Low temperature flexibility Unaffected at -20°F (-29°C) Unaffected at -20°F (-29°C) ASTM D1970
Resistance to hydrostatic head 231 ft (71 m) 231 ft (71 m) ASTM D53852
Elongation 400% 400% ASTM D4123
Tensile strength, film 4000 psi (27.6 MPa) 4000 psi (27.6 MPa) ASTM D412
Crack cycling at -9.4°F (-23°C), 10 cycles Unaffected, Pass Unaffected, Pass ASTM C836
Puncture resistance 200 lbs (890 N) 100 lbs (445 N) ASTM E154
Peel adhesion to concrete 5.0 lbs/in. (880 N/m) 5.0 lbs/in. (880 N/m) ASTM D9034
Lap peel adhesion 5.0 lbs/in. (880 N/m) 5.0 lbs/in. (880 N/m) ASTM D18765
Permeance to water vapor transmission <0.1 perms (5.74 ng/(Pa x s x m2)) <0.1 perms (5.74 ng/(Pa x s x m2)) ASTM E96, method B
Water absorption <0.5% <0.5% ASTM D570


1.    Lateral water migration resistance is tested by casting concrete against membrane with a hole and subjecting the membrane to hydrostatic head pressure with water. The test measures the resistance of later water migration between the concrete and the membrane.
2.    Hydrostatic head tests of PREPRUFE Membranes are performed by casting concrete against the membrane with a lap. Before the concrete cures, a 0.125 in. (3 mm) spacer is inserted perpendicular to the membrane to create a gap. The cured block (cured min. 7 days) is placed in a chamber where water is introduced to the membrane surface up to the head indicated.
3.    Elongation of membrane is run at a rate of 2 in. (50 mm) per minute.
4.    Concrete is cast against the protective coating surface of the membrane and allowed to properly cure (7 days minimum). Peel adhesion of membrane to concrete is measured at a rate of 2 in. (50 mm) per minute at room temperature
5.    The test is conducted 15 minutes after the lap is formed and run at a rate of 2 in. (50 mm) per minute.
6.    Test conducted at – 9.4°F (-23°C) | 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.

ADCOR®, PREPRUFE®, PROCOR®, and BITUTHENE® are trademarks, 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., 62 Whittemore Avenue, Cambridge, MA 02140 USA.

In Canada, 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: 2020-07-09