NBS Source
Newton 308 Stopaq


  • Suited for sealing against ground and surface water intrusion around pipes and cables, leading through building wall penetrations into basements and other earth retained structures.
  • For permanent stopping of ground or surface water leaks through cable and pipe wall penetrations.
  • Permanent sealing and protection of wall penetrations against gas, fire or flooding is obtained with Newton 308 Stopaq together with the Stopaq FR mortar on either side of the wall.
  • Hermetic sealing of multipurpose, horizontal lead-through wall inlets, where several pipes and cables are coming through one opening.


A single component, highly flexible compound used for the sealing of service sleeves against penetration of ground water and gases.

The product is effective at sealing around numerous services within the sleeve, even where significant water ingress exists.

The unique compound never cures, remaining permanently flexible, allowing for new services to be simply pushed through the existing repair and resealed.

The product swells by up to 10% when in contact with water and will seal a 100 mm DN service duct against up to 10 m of water pressure and will form a very effective seal against gas and water vapour.

It adheres to both wet and dry surfaces of concrete, mortar and plastic without the need of a primer.

The swelling characteristics do not create any stresses to the service joint or the structure. Once the service sleeve is sealed, Newton Stopaq FR Mortar is used to cap the installation. Stopaq FR Mortar is a fibre reinforced non-shrinking fire-resistant mortar specially produced for use with Newton 308 Stopaq that can receive new cables or conduits without the use of power tools.

Consult manufacturer's literature for relevant surface preparation.

Features and benefits:

  • Fast and easy to apply.
  • The sealing remains permanently flexible.
  • Does not require special tools for application.
  • No material waste - paste re-usable.
  • Immediate sealing - no curing time needed.
  • Provides permanent and optimal sealing of the service duct.
  • No fumes or chemical reactions, and non-toxic.
  • Environmentally friendly.
  • Adjusts to the movements of pipes and cables.
  • Allows adding and removing of conduits at any time.
  • Requires only minimal surface preparation.
  • Can adhere to both wet and dry surfaces.
  • Water and gas impermeable.
  • Has no pot/ shelf-life expiry.
  • Suitable substrates include concrete, plastic, brick, block and ceramic.

General information






Fire resistant non-shrinking mortar


Paste form


0.53 kg

Uniclass 2015

Pr_30_31_76_39 Hydrophilic sealantsPrimary


R12/110 Below ground drainage system

Product range

Waterbars, Waterstops and Waterplugs

Specification data - Hydrophilic sealants Enhanced data


To ASTM D570.


Fire resistant non-shrinking mortar.

Product Reference

Newton 308 Stopaq (SX308)

Specific gravity

1.2 to 1.5.

Pack size - Cartridge

0.4 L.

Pot life


Shelf life


2 Years.

Moisture Absorption (ASTM D570)

5–20 %.

Gap filling

10 to 40 mm.

Flash point


Installation temperature

5 to 35 °C.

10 to 35 °C.

Service temperature

-20 to +35 °C.

-20 to +95 °C.



Cured density


Pack size

0.6 L.

Pot life - 20 °C

30-40 minutes.

Final curing time

- 20 °C 24 hours.



Setting expansion


Hardness - 48 hours cured



0.26 W/mK.

Gas tightness

Natural Gas (methane) 100 mbar.


1.0 bar.


Newton 308 Stopaq Service Duct Waterproofing

Newton 308 Stopaq Service Duct Waterproofing

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