Hydrophillic Rubber Strip

Product Description

DE NEEF® SWELLSEAL® Joint is a vulcanized hydrophilic expansive rubber strip with a center pressure compensating tube for the sealing of concrete construction joints, pipe penetrations and joints in underground pre-cast elements. The flexible coextruded strip is a combination of chloroprene rubber and hydrophilic resin. DE NEEF® SWELLSEAL® Joint has an inner pressure-balancing zone which is also hydro-expansive, ensuring a perfect seal. The orange shoulder has a swelling capacity of up to 540% in contact with water. The black compression zone has a swelling capacity of 100%.

Product Application

  • Sealing joints between concrete pre-cast-elements (inspection shafts, sewers, collectors)
  • Sealing smooth cold and construction joints
  • Sealing pipe penetrations and block-outs

Product Advantages

  • Proven track record in structures subject to high water pressure
  • Non-sag when correctly placed around pipes and in vertical joints
  • Easily installed by nailing or using DE NEEF® SWELLSEAL® WA
  • Chemically inert and resistant to petroleum, mineral and vegetable oils and greases
  • Exerts the least amount of expansion pressure of the DE NEEF® SWELLSEAL® preformed waterstop line
  • Reversible swelling properties

Packaging & Handling

1 roll DE NEEF® SWELLSEAL® 2010 = 32.8 ft (10 m).

1 case DE NEEF® SWELLSEAL® 2010 = 3 rolls (15 lbs).

Unlimited shelf life when stored in a dry place in its original packaging.

Installation Guidelines

Prior to the installation of DE NEEF® SWELLSEAL® Joint, the surfaces should be level, dry, clean and free of oils, dust and laitance.

DE NEEF® SWELLSEAL® Joint can only function properly in a confined space in order to develop sufficient expansion pressure and ensure waterproofing.

The expansion of DE NEEF® SWELLSEAL® Joint will create pressure, which needs to be counteracted by at least 3 3/4 ” of concrete cover on all sides (installation in the middle of the joint is preferred between the rows of rebar). DE NEEF® SWELLSEAL® Joint can be applied on both smooth and rough concrete.

On smooth concrete:

Roll the DE NEEF® SWELLSEAL® Joint between the inner and outer rebar and nail down with a gun (4 to 5 nails per yard) or use DE NEEF® SWELLSEAL® WA.

On rough concrete:

Gun DE NEEF® SWELLSEAL® WA in a 3/8” bead between inner and outer rebar. Press DE NEEF® SWELLSEAL® Joint firmly into the mastic or epoxy. For vertical applications, apply extra nailing (4 to 5 nails per yard).

Install DE NEEF® SWELLSEAL® Joint with smooth surface upwards. Installation during rain or in prolonged contact with water can result in a premature swelling of the strip, which should be avoided.

If DE NEEF® SWELLSEAL® Joint is exposed to water prior to encapsulating in concrete, the strip must be allowed to dry and shrink back to its original configuration. Roll ends are simply butted together to ensure a waterproof seal. Do not install in overlap. The strip needs to be in contact with the joint over its full length. 

Health and Safety

Always use protective clothing, gloves and goggles consistent with OSHA regulations during use. Avoid eye and skin contact. Do not ingest. Refer to SDS (Safety Data Sheet) for detailed safety precautions. SDS’s can be obtained from GCP Applied Technologies or from our web site at


Requires 3 3/4” concrete cover on all sides. Avoid installation during heavy rain. Use only in tight joint applications such as between precast members or poured concrete.


Elongation at break Black tube 610% Orange shoulders 670% ASTM D412
Shore A Hardness Black tube 53 Orange shoulders 50 ASTM D2240
Specific density 1.23-1.27 ASTM D471
Swelling capacity of black compression zone 50% (1 day) 
100% (4 days)
Swelling capacity of orange hydrophilic zone 220% (1 day) 
540% (4 days)
Tensile Strength Black tube Tensile strength Orange shoulders 1,706 psi 
1,308 psi
Appearance Orange/black rectangular strip  
Dimensions 1” x 5/16” (25mm x 7mm)  

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