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RIW Cementseal - Waterproof Coating System

Verified by manufacturer 7 months ago


Cold applied, cementitious waterproof coating system.

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+44 (0)1753 944200 Website


  • Designed to be used to prevent water ingress into basements, cellars and other below ground structures.
  • It can also be used for temporary waterproofing in new construction to protect from water ingress prior to weatherproofing of the structure.


A cold applied, cementitious waterproof coating system that is polymer modified to give excellent adhesion and abrasion resistance.

Features and benefits:

  • Dense matrix offers low permeability to water, even at 10 bar pressure.
  • Totally waterproof and will also resist negative water pressure.
  • Gives enhanced resistance to carbonation.
  • Will readily accept flooring and other decorative finishes.
  • Materials are pre-packaged and only require mixing on site to give a slurry, which can then be easily applied by brush, squeegee or spray.
  • Non-toxic when cured.
  • CE marked.

Primer/ curing agent RIW Cementseal Primer:

  • An environmentally friendly, multi-functional water based compound, formulated on an aqueous acrylic copolymer.
  • The product chemically reacts with cement, to produce a durable surface seal, which stabilises the substrate and reduces the evaporation of water.
  • Provides efficient sealing of horizontal concrete substrates, by stabilising the surface and preventing out-gassing, prior to the application of RIW Cementseal.
  • The product will also act as a curing agent for newly placed cementitious mortars and coatings, by helping to reduce the amount of water evaporating from the surface.
  • The primer is also used when applying joint tape.

Joint tape RIW Cementjoint:

  • An advanced, elastomeric, highly tear resistant, breathable, waterproof composite tape.
  • Permanently elastomeric composite membrane embedded in backing fabric, exhibiting over 600% elongation.
  • Impermeable to water under 10 bar hydrostatic pressure, yet allows the free passage of water vapour.
  • Good UV and weathering resistance and highly resistant to a wide range of chemicals.
  • When embedded in RIW Cementflex, it gives a highly flexible, impermeable seal over ‘live’ cracks and expansion/ construction joints.


  • The areas to be treated must be free from all unsound material, e.g. dust, oil, grease, corrosion by-products and organic growth.
  • The strength of the concrete sub-base should be a minimum of 20 N/ mm².
  • Deck or floor areas should be primed with RIW Cementseal Primer.

Application temperature:



Protect the mortar from strong sunlight and drying winds with RIW Cementseal Primer, polythene sheeting, damp hessian or similar.

General information





Warranty description

RIW Limited’s waterproofing products will, subject to normal service conditions, provide an effective barrier to the transmission of liquid water and water vapour for the life of the building in which they are incorporated., The products must be installed in accordance with RIW written instructions, and following installation must not be subjected to any damage or long-term UV exposure.



Pr_20_31_53_65 Polymer-modified cementitious mortarsPrimary


J10/110 Proprietary mortar

Specification data - Polymer-modified cementitious mortars

Product Reference

RIW Cementseal

Primer/ curing agent

Not required.

RIW Cementseal Primer.



Floor coatings, or for temporary waterproofing.


Joint tape

Not required.

RIW Cementjoint.

Application thickness

Floors: 2 mm, applied in single coat; Soffits and vertical surfaces: 2 mm, applied in two coats; Temporary waterproofing: 1 mm, applied in single coat.


40–45 N/mm² (after 28 days).

Application temperature


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Platform Compatible Version




Revit 2015


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