arcaflex repair cracks in concrete

Use ARCAFLEX, our flexible joint mortar to repair and seal cracks or large (>3mm) and joints in all masonry surfaces, cement, steel and pvc substrates:

  • in basement walls,
  • wall to floor joints,
  • swimming pools

ARCAFLEX FLEXIBLE JOINT MORTAR comes in a pre-batched ready to use kit and hardens to an elastic waterproofing sealant making it ideal for use where increased flexibility and durability are required.

ARCAFLEX FLEXIBLE JOINT MORTAR adheres excellently to all building materials.

ARCAFLEX FLEXIBLE JOINT MORTAR is designed to fill and waterproof joints.

flexible joint mortar

Arcaflex is used to treat large joints or cracks (>3mm) which are too large to fill and reinforce with Arcacem S2 and Arcafibre.


ARCAFLEX is often used with ARCACEM - ARCACEM S2



Complementary and / or Alternative Solutions

2 pack sizes:
2 kg and 10 kg

coverage rate

drying time

clean up


  • Fills joints and repairs cracks in horizontal and vertical surfaces

  • Ideal for repairing cracks in concrete (basements, swimming pools)
  • In conjunction with ARCACEM S2, will fill wall to floor joints to form a fillet  (Click here to see how)

  • Treats active cracks on a surface prior to applying waterproofing coatings
  • Excellent bonding to most building materials (iIdeal for restoration work)
  • feather edges easily
  • high strength and flexibility
  • will accomodate a concrete slab's expansion and contraction
  • Repairs and waterproofs joints and large cracks
  • Pre-packaged kit ready-to use

Pre-batched 2 component kit.


Once mixed use within: 3 hours


Curing time: 1 to 10 days*


*Note: The product will dry quickly; full curing time will depend on thesize of the area being treated, the porosity of the substrate and relative humidity.


Technical information:

Composition: special cements, selected sands, specific additives and synthetic resin in aqueous dispersion.

Component A : 50% weight

  • aspect: grey powder
  • density: 1.1
  • maximum grain size: 0.4mm

Component B: 50% weight

  • aspect: milky white liquid
  • density: 1
  • pH=3

Characteristics at application (20°C) Density of paste: 1.45
pH = 12
Adhesion to cement after accelerated ageing: 18.5 daN/cm²
Elongation at 50% of breaking force: 105%

Instructions for use




Application Conditions
Do not apply if the temperature is <5°C or >30°C
Do not apply on frozen substrates or freezing is forecast within 48 hours of the application.
Do not apply under hot dry sun.


Product Preparation
Mix the 2 components in equal proportions (in terms of weight)
Pour the component B into component A and stir with a trowel or an electric mixer until a homogeous paste is obtained.


Surface Preparation
The substrate must be, brushed clean and free of any loose material, dust and any loose particles which will prevent proper adhesion: laitance, separating agents, etc.
The surface must be clean and cohesive.
Wash and vacuum out cracks and joints.
Place a backing foam at the bottom of the joint.
Do not use in the presence of running water (major leaks).



  • Widen the crack using a chisel and hammer to a minimum of 2x 4cm and break away any deteriorating concrete (the edges of the crack should be vertical or beveled in an inverted “v”).
  • Note: The width of the crack should be twice as large as the depth. See illustration below.
  • Once the crack has a wider base, clean thoroughly using a wire brush, a damp cloth or a vacuum to remove small particles that will prevent the adhesive from bonding to the concrete surface.
  • Prepare the product as indicated above
  • Insert and pack down the flexible mortar to fill the entire area.
  • Level off with a wet trowel
illustration: Backer rod
arcaflex bond breaker
Illustration width-to-depth ration
arcaflex width to depth ratio


N° cm² of the joint section x N° linear metres x 0.140kg

A 2kg tub will treat approximately 2 linear meters (section 8cm²)
A 10kg tub will treat approximately 8 linear meters (section 8cm²)

1 day

The curing time will depend on the surface area, the porosity of the substrate and relative humidity and can vary from 1 to 10 days.

Clean tools with water immediately after use.



About Us

Arcane Industries has been developing,creating , and selling waterproof, water repellent, water resistant, decoration products for over 20 years.

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We are available to answer your questions on:
020 3151 3120 or by mail: contact@arcane-industries.co.uk

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