The Construction Centre
Magnifying Glass



Visit our website

Find out more about us:


Call us now

01344 397 777

  • Imperial War Museum North at Dusk
  • Paradise Wharf
  • Waterstop
  • Magistrate Court
  • The Shard in progress
  • The Bullring
  • National Film Archive
  • Saxton Parade, Leeds
  • Flexiseal, Manchester
  • RIW Structureseal
  • Structureseal
  • RIW Flexiseal
  • Cementseal, Gibraltar
  • Cementseal, Gibraltar
  • Cementseal
  • Toughseal
  • Heviseal
  • Toughseal, Gibraltar
  • Multi-joint
  • RIW Sheetseal
  • RIW Plaster Drain
  • RIW Cavity Drain
  • RIW Cavity Drain P5
  • RIW Liquid GM

RIW Company Profile

RIW is a renowned provider of a diverse array of waterproofing systems for above, below and ground level applications. The company offers complete waterproofing assurance to architects and engineers and is well-known for the expert Technical Advisory Service which provides a full consultation and design service.

RIW will oversee any waterproofing strategy from the initial enquiry through to completion, including technical advice and guidance, preparation of sectional details, approval of drawings, site inspections and continuous site support. The innovative waterproof solutions include RIW Tilesafe and RIW Cement Based Coatings and the more traditional RIW LAC system.


RIW has over 90 years of experience in structural waterproofing and the company offers a complete, free technical service to assist architects, surveyors, engineers and contractors with every aspect of the design and specification of structural waterproofing systems. The technical centre also provides data sheets, typical details, NBS clauses, method statements and MSDS details. The in-house advisory team can also offer advice and guidance on commercial matters such as product trade pricing, availability, distribution network, specialist waterproofing contractors and logistics. RIW works closely with a UK wide network of specialist waterproofing contractors who have a great deal of experience in installing structural waterproofing systems. RIW’s products are supplied through a national network of distributors and stockists.


Waterproofing is required for numerous applications such as internal and external tanking, damp proof courses, raised access floors, plant rooms, podium decks, superstructures, cavity drainage systems, retaining walls, wet rooms, lift pits, planters, movement joints, gas/radon resistance, DPC and cavity trays and temporary waterproofing.

The product range includes:

Liquid Applied Systems

The comprehensive range of cold applied liquid waterproofing coatings are usually applied in two colour-coded coats for in-built quality control. Once cured, the systems create a seamless and fully bonded liquid damp-proof membrane which halts the ingress of water and water vapour. Liquid applied systems are suitable for basement tanking, damp proofing, plant rooms, podium decks and radon protection and offer high levels of flexibility, durability, gas-proofing and abrasion and chemical resistance capabilities. Options include:

  • Flexiseal: A liquid applied system based on polyurethane resins which offers chemical, sulphate and radon resistance
  • Heviseal: A bitumen solution filled with fibres and minerals to provide a UV resistant waterproof coating
  • LAC: A bitumen solution which dries to form a radon and sulphate resistant , plasterbond waterproof coating
  • Toughseal: A waterproof coating based on epoxy resins which is Class 1 fire rated, UV stable, impact resistant and colour-coded
  • Liquid GM: A specially designed gas protection and waterproof membrane
  • Repel AC: A single component, water-based decorative damp proofing coating which offers protection against carbonation and water ingress and is resistant to mould and fungus growth.

Sheet Applied Systems

The range of cold applied, pre-formed self-adhesive HDPE sheet membranes are supplied in a roll. They prevent the passage of water and water vapour and are suitable for basement tanking, gas proofing, damp proofing and wet room applications. All HDPE sheets have a factory controlled thickness for in-built quality control and ease of application. Options include:

  • Sheetseal 226: A HDPE film coated with rubber bitumen to form a preformed waterproof membrane which is flexible, self-healing and radon resistant
  • Sheetseal GR: A self-adhesive bitumen membrane which incorporates an aluminium foil layer that creates a waterproof and gas proof membrane which is methane resistant and self-healing
  • Tilesafe: A self-adhesive bitumen membrane which incorporates a woven glass fibre mesh to form a waterproof membrane compatible tile adhesive.

Sodium Bentonite Systems

Sodium bentonite systems are highly effective waterproofing geo-composite membranes and compounds which are generally pre-applied, prior to placement of in-situ concrete and form a strong mechanical bond to the concrete to form a dense, monolithic, impervious and self-healing waterproof system. Options include:

  • Structureseal: A highly effective composite incorporating high strength geotextile and high swelling sodium bentonite clay
  • Waterstop: A hydrophilic waterstop based on sodium bentonite material which is designed to permanently seal in-situ concrete construction joints
  • Sealing Compound: A trowel-grade sodium bentonite/butyl rubber-based sealant used for detail work and surface preparation in conjunction with Structureseal
  • Granules: The chemically treated granules are used as a detailing product in conjunction with the Structureseal system.

Structural Drainage Systems

A comprehensive collection of high performance plastic drainage systems for water management which have been developed to control and discharge ground water entering a basement or substructure in accordance with BS 81902:2009. Products include:

  • Cavity Drain: A profiled HDPE cavity drain system which is used to collect and channel water entering a basement to a suitable disposal location
  • Double Drain: A HDPE profiled drainage board which features a filter fabric which is designed to protect waterproof membranes and relieve hydrostatic water pressure
  • Aqua Pumps and Sump: Mains and battery operated pumps and sump used to remove ground water from basements and substructures
  • Aqua Channel: A pre-formed drainage conduit which is fitted around the perimeter of a basement slab to control water ingress.

Cement Based Systems

The cement based systems comprise waterproof polymers, modified cement based coatings and repair mortars that can resist up to 100m head of negative water pressure. The systems are cold applied by brush, notched trowel or sprayed on and create a seamless, fully bonded, durable, resilient and flexible waterproof polymer solution for basements, substructures, podium decks and water containing structures. Options include:

  • Cementseal and Cementflex: Highly durable waterproof cement based coatings that are resistant to 100m head of water pressure
  • Cementfill FC and HB: Single component, thixotropic, polymer modified waterproof fairing coat and repair mortars for concrete and masonry
  • Cementjoint: An advanced, elastomeric tear-resistant and breathable composite tape for use with Cementseal
  • Cementseal Primer: A multi-functional, water-based primer for concrete and masonry.

DPC and Cavity Tray Systems

High performance polymeric DPC and cavity tray systems which have been developed to provide damp proof walls by halting the ingress of moisture from the ground, through masonry and into the fabric of the building at all levels. Sheetseal 9000 is a range of DPC and cavity tray systems which contain polyester fibres to increase tensile strength and elongation at the break.

Movement Joints

Movement joints are used to relieve or absorb anticipated movement between structural elements which are generally caused by thermal expansion or contraction, settlement, load transfer, dead loads and seismic activity. Multijoint is a closed cell, cross-linked ethylene vinyl acetate copolymer waterproof EVA foam which is resistant to salts, UV and chemical attack and is suitable for exposed exterior applications.

RIW is committed to providing clients with a comprehensive range of products and services and has established a highly respected reputation within the construction and waterproofing industries. The experienced and professional customer service and technical teams are on-hand to provide in-depth advice and guidance on all the systems available and welcome enquiries from architects, engineers, specifiers and contractors. Products are widely available through a national network of stockists.


ARC House
Terrace Road South
RG42 4PZ

Tel: 01344 397 777


RIW News

What We Do