Seal-it® 235 ELASTO-STOP

Seal-it® 235 ELASTO-STOP is a high-quality, elastic putty for sealing and filling of heritage glass, based on silicone technology, that cures by moisture into a durable rubber that retains its elasticity.



  • Specially designed as a putty that retains its elasticity, for application of seam seals for single-pane, insulating and heritage glass, in wooden, steel and concrete frame rabbets.
  • As a higher-quality substitute for traditional putty in heritage and public buildings, such as canal-side buildings, farmhouses, schools, station buildings, etc.
  • As an elastic filler for smoothing/levelling surface damage such as screw and nail holes in glazing beads and other wooden parts.
  • Repair putty for damaged seals in seams, based on silicone technology.


  • Durable, retains elasticity, fast moisture-curing.
  • Excellent adhesion without primer on practically all surfaces, even when moist.
  • Superb workability using a professional caulk gun, due to the special yellow XL spout.
  • Easy to shape with a suitable jointing tool (PALU) and/or finishing block.
  • Good resistance to UV, weather, water, moisture and ageing.
  • Non-corrosive to metals.
  • Extremely low-maintenance, does not crack, split, wrinkle or petrify from drying out.
  • Compatible in direct contact with edge seals on insulating glass and PVB-laminated glass.
  • Isocyanate and solvent free.
  • Odourless, adhesive-free, bubble-free and non-shrink fast-curing hybrid system.

Application conditions

  • Application temperature (ambient and surface) between +5°C and +40°C.
  • On stable, compatible, clean, uncontaminated, grease-free and dust-free surfaces.
  • Use a suitable brush to remove any loose particles from the surface.
  • Degrease the surface properly using Seal-it® 510 Cleaner.
  • Seal-it® 235 ELASTO-STOP 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.
  • Minimum dimension of the seam seal (triangular joint): 10 mm x 10 mm.
  • Use a professional caulk gun fitted with yellow XL spout, shape using a scraper and/or finishing block.
  • Use Seal-it® 550 FINISH to apply a smooth and tight finish, before skin formation.

Standard product line


12 x 600 ml foil pack





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


  • VOC emission class A+

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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