Seal-it® 320 MS Floor-SL

Seal-it® 320 MS Floor-SL is a self-levelling, high-quality professional sealant for horizontal expansion joints in floors, that is based on hybrid technology and moisture-cures into a durable rubber that retains its elasticity.



  • Specially developed as a self-levelling, highly elastic sealant that is suitable for horizontal expansion joints and offers lasting absorption of significant movements.
  • Seal connecting and dilation joints between concrete parts in floors, galleries, storage rooms, parking garages, staircases, balconies, platforms, landings, terraces, tunnels and roadway and bridge components.
  • Industrial joint sealing, around cable penetrations, machine bases, drainage systems and steel structures.


  • Self-levelling, good fluidity, no rework needed, efficient and user-friendly.
  • Excellent adhesion without primer on practically all surfaces, even moist ones.
  • Durable, retains elasticity, maximum movement capacity of 25%.
  • Good absorption of acoustic and mechanical vibrations.
  • Good resistance to discolouration, UV, weather, water, moisture and ageing.
  • Paintable with water-based paint systems.
  • Free of isocyanate, solvents and silicone.
  • Non-corrosive to metals.
  • Odourless, adhesive-free, bubble-free and non-shrink curing hybrid system.

Application conditions

  • Application temperature (ambient and surface) between +5°C and +40°C.
  • On clean, uncontaminated, stable, compatible, dust-free and grease-free surfaces.
  • Ensure proper joint dimensions, for proper absorption of any movements.
  • Degrease the surface properly using Seal-it® 510 CLEANER.
  • Use a suitable brush to remove any loose particles from the surface.
  • Seal-it® 320 MS Floor-SL has a broad bonding spectrum, but highly porous surfaces should be pre-treated with Seal-it® 520 PRIMER and non-porous surfaces with minimal bonding should be treated with Seal-it® 525 Clean & Bond.
  • Use Seal-it® 550 FINISH to apply a smooth and tight finish, before skin formation.

Standard product line


12 x 600ml foil pack

Concrete grey


SI-XXX-XXXX-XXX = Article number.
Other colours and/or packaging on request.


Technical support department

Connect Products has a state-of-the-art R&D laboratory, where experienced specialists continuously research and develop sealants, adhesives and PU foams. Customers and clients can have products researched, tested and developed by this department. You can also contact us for technical advice, tips, project support, warranty certificates, requests and other technical questions. We will be happy to assist you with high-quality technology.

Call us on +31 (0)183 731 400 or send us an e-mail.

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