Hydro-expansing rubber waterstop

Code: PRS.0181

Components: 1

Appearance: Stripe

Sealing waterstop based on a special mixture of natural and synthetic rubbers and hydro-expansive hydrophilic agents: in contact with water, it increases its volume up to over 3 times the original size. SEALGUM 20.20 is a simple and easy to apply sodium bentonite waterstop; it does not require any special preparations of the media, pre-shaped seats etc.

General characteristics


Shelf-life: 12 months


Density: 1.26 kg/dm³


Hydroexpansive product: +300 %

Technical specifications

Surface section

400 mm²


36 _

Resistance to water pressure

5 bar

Fire resistance

B 2 _

Non-toxic material

Available colours

- Blue

Packaging and dimensions

- Roll 5 m

- Box: 9 x (Roll 5 m)


1.1 m/m: Use 1 metre of SEALGUM 20.20 for each linear metre, being careful to place 5-10 cm of the product alongside the end/start roll points to guarantee the permanent water tightness of the system.

Use fields

Rigid construction joints and connections with safe and permanent hydraulic seal.

Use method

SEALGUM 20.20 must be laid on the bed surface and fixed by nailing (a steel nail plus washer approximately every 25 cm). The joints between the waterstop kerbs are sealed by simply flanking and not by overlapping the ends. The positioning must ensure a coverage of 18-20 cm in the concrete, in order to contain the expansive action generated hydration.

In the case of particularly uneven or rough surfaces, it will be possible to apply SEALGUM 20.20 with the aid of the hydro-expansive sealant in cartridge FLEXSEAL 300.

Application methods

- Hammer

Permitted supports

- Concrete

- Cement-based or lime-based mortars

Warnings, precautions and Ecology

Carry out preliminary expansion tests in case of aggressive groundwater or with a high salt content.


Products on display

  • Osmocem
  • Opus Dry
  • Syntech Poliurea