RIW Flexiseal 500 HG Data Sheet

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Flexiseal 500 HG is a two-component, reactive, fast-curing, hand-applied waterproofing membrane which provides a continuous, tough and flexible seamless coating for roofs, podium decks, terraces and balconies. Flexiseal 500 HG is based on advanced resin technology.

 

 

Surface Preparation

All surface coating systems are dependent on the quality of surface preparation.

Concrete

New concrete substrates should be a minimum of seven days old and constructed in accordance with BS    EN 1992. The substrate must be clean, dry and structurally sound. It must be free from laitance, oils and all other surface contaminants.
Where the use of a non-structural screed or a lightweight concrete substrate is proposed, contact Technical Department as these materials often have low cohesive strength or retain water in open pores.

Steel

On steel surfaces all rust, dirt and contamination should be removed to expose bright metal to achieve a surface finish to comply with Swedish standard Sa 2.5.
For compatibility with other construction materials or where additives, cement replacement or curing compounds have been used please consult the Technical Services Department.

Application

Primer

The substrate must be primed with FLEXISEAL 500 CONCRETE PRIMER prior to application of the FLEXISEAL 500 HG membrane with a brush or roller.

Membrane

RIW FLEXISEAL 500 HG system is poured onto the substrate and spread using a trowel and / or brush. Spread using a trowel, brush, notched squeegee or skid leveller.
For vertical surfaces the material should be applied by brush. The material should be applied in two even coats to give a minimum dry film thickness of 1mm per coat.
FLEXISEAL 500 HG can be trafficked or loaded once fully cured.

Coverage

Coverage rates are based on a smooth substrate and will vary with surface texture and porosity.
Primer: refer to separate datasheet
Membrane typically 1.4kg/m²/coat 
Single coat coverage 2.8kg/m²

Cleaning

All tools and equipment should be cleaned with acetone before the material is allowed to cure.

Packaging & Storage

Primer: refer to separate datasheets
RIW FLEXISEAL 500 Membrane: 20kg, resin only
BPO Liquid Catalyst, pack: 5kg & 20kg (for use with Hand Grade)
All components of the FLEXISEAL 500 system should be stored in cool, dry, protected conditions, out of direct sunlight and in accordance with the relevant site Health & Safety regulations. Storage temperature must not exceed 25°C. Do not store near naked flames or foodstuffs.
Stored in unopened containers, under the correct conditions, the components have a minimum shelf life of twelve months. If your product is more than twelve months old you must contact Technical Service before use.

Benefits

  • Water and water vapour barrier
  • Seamless & fully bonded coating
  • Tough & flexible, able to accommodate differential movement
  • Can be applied in one or two coats
  • Cold applied by hand - No hot works
  • Simplifies application to irregular profiles & complex details
  • Provides access to restricted areas
  • High substrate and inter-coat adhesion
  • Excellent crack bridging capability
  • Good chemical & UV resistance
  • Rapid cure and unaffected by high humidity

Applications

Unexposed applications on:

  • Podium decks
  • Elevated decks (terraces & balconies)
  • Roofs - including Green and Bio-Diverse roofs

Applied To

  • Concrete
  • Masonry
  • Steel

Product Uses

RIW Flexiseal 500 is ideal for applications to all podiums, buried roofs, terraces and balconies. Can be applied at a high output to any sized application. In particular, convenient for smaller areas with restricted access.

Product Features

  • Unaffected by high humidity
  • Rapid cure even at low temperatures
  • Able to carry load or traffic after one hour
  • Remains effective for the life of the structure
  • Resistant to chloride ions
  • Excellent chemical, abrasion and impact resistance Excellent UV and weather resistance
  • Crack bridging capability
  • High bond strength to substrate Excellent intercoat adhesion
  • No critical overcoating time on any coat
  • Applied only by authorised and trained contractors

Technical Data

RIW FLEXISEAL 500 HG Can be applied at temperatures between 0°C and 30°C
Product    Value
FLEXISEAL 500 Winter Grade    0°C - 15°C
FLEXISEAL 500 Summer Grade    10°C - 30°C

Ancillaries

RIW has a range of products to compliment the FLEXISEAL 500 HG system. These include:

  • FLEXISEAL 500 CONCRETE PRIMER 5 KG
  • FLEXISEAL 500 METAL PRIMER 5 KG
  • FLEXISEAL 500 LIQUID INITIATOR 5 KG
  • FLEXISEAL 500 POWDER INITIATOR 100G
  • FLEXISEAL 500 POWDER INITIATOR 150G
  • FLEXISEAL 500 POWDER INITIATOR 160G
  • FLEXISEAL 500 B2 FILLER 20 KG
  • SMOOTHING COMPOUND H 3.2KG – a levelling product
  • FLEXISEAL 500 ADHESIVE 4.85 KG
  • FLEXISEAL 500 FLEX SEALANT V 4.85 KG – flexible sealants for all joints and cracks
  • FLEXISEAL 500 REINFORCING MESH

Health and Safety

Please refer to our safety datasheets and information sheets  for further information.

Flexiseal 500 HG Downloads

 

 

 

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Last Updated: 2026-03-22

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