DE NEEF® Dry Oakum

Product Description

DE NEEF®'s Dry Oakum is a 2” diameter natural jute rope comprised of 8 strands, having a twist of approximately 1-1/4 turns per foot. The loose twist is easily unraveled to allow for fitting into joints or annular spaces from 1/2” to 2”. Single strands can be broken down to fit into openings smaller than 1/2”. When combined with DE NEEF® PURe polyurethane grouts and water, the system swells to seal cracks, joints, and annular spaces around pipe penetrations. The system is ideal for pre-injection sealing of openings or to stop flowing water prior to final injection of chemical grout.

Product Applications

  • Sealing joints and cracks
  • Sealing around pipe penetrations
  • Stopping flowing water
  • Pre-injection surface sealing

Packaging & Handling

Dry Oakum is provided in a 50 lb. box

Approximate yield:

1/2” strands = 1000 ft.
2” strands = 125 ft.

Store in dry conditions.

Physical Properties

Color Brown
Weight 0.4 lbs. / ft at 2” dia.
Diameter Approx: 2” (8 strands twisted)
Conforms to: Federal Specification HH-P-117

Note: The data shown above reflects typical results based on laboratory testing under controlled conditions. Reasonable variations from the data shown above may result.

Product Advantages

  • Very absorbent natural jute
  • Easy to cut to size
  • No oils or tars added
  • Strands easy to separate
  • Conforms to any shape opening

Installation Guidelines

Warning: Use proper tools and safe cutting techniques to prevent injury while cutting Dry Oakum. Work on a flat well lighted surface and make all cutting motions away from the body. Always wear gloves, goggles and protective clothing when installing chemical grout soaked Dry Oakum. Refer to the manufacturers safety instructions for the resin being used before proceeding.

Installation Instructions:

  1. Clean area to be sealed prior to installing saturated oakum to facilitate a good bond to the substrate.
  2. Cut Dry Oakum into workable lengths. (18”-24”) Properly saturated and installed oakum will create a seal to itself, so several short sections may be used.
  3. Loosen fibers with the hands to enhance material absorption.
  4. In a clean pail pour DE NEEF® PURe polyurethane grout and add catalyst if required. (Refer to the DE NEEF® technical department for the correct choice of chemical grout for your application.)
  5. In a second pail, pour clean water to be used to initiate the chemical grout reaction.
  6. Prior to saturating the Dry Oakum with chemical grout, wet the substrate with water and have a method available to apply water to the surface of saturated oakum after it is installed.
  7. Using a gloved hand, submerge the Dry Oakum into the pail of chemical grout.
  8. Work the resin into the Dry Oakum; similar to getting a sponge to soak up liquid.
  9. Remove the saturated oakum from the grout pail. With a gloved hand, form a circle with the thumb and fore finger and pull the saturated oakum through the circle. Loosely grip the saturated oakum as it passes through the hand to remove excess surface resin without removing the resin that has saturated into the strand of oakum. DO NOT WRING OUT!
  10. Dip the saturated oakum strip into the pail of clean water to initiate the chemical grouts reaction.
  11. Immediately place the saturated / wetted strand of Dry Oakum into the crack, joint or annular space. A tool such as a screwdriver, punch, or metal rod may be used to facilitate saturated oakum placement.
  12. Mist or spray additional water onto the surface of the saturated oakum. Use caution only to wet the surface and not to wash the resin out of the oakum.
  13. Allow the chemical grout to fully react.
  14. Repeat with additional strips as required to fill the entire area to be sealed.
  15. Excess grout that expands out of the sealed area may be removed by mechanical means after the grout is fully cured. Use caution not to dislodge the newly formed seal.using this product.

Health and Safety

Always use protective clothing, gloves and goggles consistent with OSHA regulations. Avoid eye and skin contact. Do not ingest or inhale fibers.

For emergencies, call CHEMTREC 1-800-424-9300.


Wider cracks and joints sealed with chemical grout saturated dry oakum may require additional grout injection to achieve seal if excessive pressures or high water flow are present. | 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.

DE NEEF is a 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: 2023-06-29