PREPRUFE® Hydrophilic Sealant

Single component, hydrophilic polyurethane sealant

Product Description

A caulk-applied hydro-swelling sealant designed as a water stop for use around penetrations and in both horizontal and vertical construction joints.

Product Advantages

  • Solvent free
  • Expansion—Will expand to more than 200% of its original cured volume
  • Can be applied to damp surfaces
  • Adhesion—Strong adhesion to concrete, steel, HDPE, PVC, and other common building materials
  • Ease of application—Can be applied with a standard caulking gun


PREPRUFE® Hydrophilic Sealant is ideally suited for the following uses:

  • As a water stop around pipe penetrations, rebar, utility conduits and other penetrations
  • Horizontal and vertical construction joints in concrete surfaces
  • As a detailing accessory to the PREPRUFE® Waterproofing System

Application Procedures

Safety, Storage and Handling Information

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 are available at

PREPRUFE® Hydrophilic Sealant is available in 10.5 fl oz cartridges.

PREPRUFE® hydrophilic Sealant has a shelf life of 12 months from the date of manufacture when stored in the original unopened cartridges between 40 °F (4 °C) and 90 °F (32 °C).

Surface Preparation

All surfaces must be clean, dry and free from dirt, grease oil, dust or other contaminants. PREPRUFE® Hydrophilic Sealant may be applied at temperatures of 25 °F (-4 °C) and above. When installing in temperatures below 40 °F (4 °C) the material should be kept in a heated truck or trailer prior to application.


Apply PREPRUFE® Hydrophilic Sealant with a caulking gun. The sealant should be applied in an uninterrupted minimum 3/8 inch (9.5 mm) wide and thick bead.

Refer to PREPRUFE® System detail drawings at

Concrete Placement

Normal weight structural concrete should be placed carefully to avoid damage to the PREPRUFE® Hydrophilic Sealant.

PREPRUFE® Hydrophilic Sealant must cure for a minimum of 6 hours before concrete placement and a minimum of 24 hours before shotcrete placement.

PREPRUFE® Hydrophilic Sealant should be encapsulated with a minimum 3 in. (76.2 mm) concrete cover.


Not suitable for use in movement joints.


Clean tools and equipment with mineral spirits. Mineral spirits is a combustible liquid and should be used only in accordance with the mineral spirits manufacturer’s safety recommendations. Do not use solvents to clean hands or skin.


Unit size 10.5 fl oz (30 mL) cartridge
Packaging 12 cartridges/carton

Physical Properties

Solids 100%  
Density 1.45 ASTM D357
Elongation 600% ASTM D3574
Tensile Strength 300 psi ASTM D412 | North America customer service: 1-877-4AD-MIX (1-877-423-6491)

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