Belzona 4511 (Magma-Flex Hi-Build)

Elastomeric Sealant for Vertical, Horizontal or Sloped Expansion Joints

Belzona 4511

A fast-curing, 2-part flexible sealant designed to provide effective sealing of construction and expansion joints on concrete, stone, brick and other surfaces. This solvent-free material is a cost-effective and high performance alternative to conventional mastics and sealants, providing joints with up to ±12.5% flexibility and outstanding weather and chemical resistance. It does not require any hot work and cures quickly, ensuring a safe and easy application.

Key benefits:

  • Provides expansion joint flexibility of up to ±12.5%
  • Downtime reduction due to its fast-curing properties
  • Reduced future maintenance and eliminates the need for expensive structural rebuild
  • Reduced health and safety risks as it is solvent-free
  • Application and cure at room temperature - no hot work involved
  • Excellent weather and chemical resistance against a wide range of chemicals
  • Easy to mix and apply manually with no specialist tools required
  • Excellent adhesion to surfaces including concrete, brick, stone and steel

Applications for Belzona 4511 (Magma-Flex Fluid) include:

  • Building joints sealing on vertical surfaces such as building faces, walls, parapet walls, retaining walls, dams, canal linings, bridges, overhead offsets, pipelines, sidewalks, concrete water tanks, spectator areas (bleachers, stands)
  • Expansion joints sealing on horizontal or tilted flat surfaces such as indoors/outdoors floors, ramps, roads, bridges, containment areas, railways, car parks, roofs, paving slabs, foundations
Key technical data:
Working life at 22°C (72°F)  90 minutes
Time to mechanical cure at 20°C (68°F) 4 days
Peel adhesion (ASTM D429) 39.7 pli (708.8 kgs/m) on blasted steel
Volume capacity 3354 cm³ (204.8 cu.in.) per 4.2 kg
Bonds to Concrete, stone, brick, steel, other Belzona 4000 Series materials and many more
Typical applications Elastomeric expansion joint sealant
Unit size 4.2 kg. Pack sizes may vary locally. 
Availability* North and South America

* All products are subject to regional restrictions. Check with your local Distributor for more information


More information:

For more information about Belzona 4511 please contact us or find your local distributor.

You can apply to join Belzona Connect to access additional information including SDS and instructions for use.

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