Sealant Jargon Buster

  • Acetoxy – A product that cures by a reaction with moisture in the air, giving off an odour of Acetic Acid or vinegar. Acetoxy cure sealants shouldn’t be used when they are primarily in contact with alkaline substrates such as concrete.
  • Acrylic – Water based sealants which cure through the loss of water into the substrate. These products are commonly used for interior finishing and can be overpainted once cured.
  • CE – There are four main types of approval under the sealant CE Mark:
    • F – Façade use which is split into two sub categories with FINT meaning internal use only and F EXT INT meaning the product can be used both internally and externally. F EXT INT is then split into various classifications:
      • P – Plastic which means the product has limited elastic recovery and behaves more like a plastic bag
      • E – Elastic which means the product behaves more like an elastic band
      • HM – High Modulus
      • LM – Low Modulus
    • G – Glazing use
    • S – Sanitary use which is only approved for internal use and is split into two sub categories S and XS with the latter being the more stringently tested of the two. A number will always follow the S or XS with 1 showing the least biological growth and 3 showing the most, basically meaning S3 is the lowest classification and XS1 is the highest.
    • PW – Pedestrian Walkway use
  • Fire Rating – The measure of a sealants ability to maintain its insulation and integrity in a joint when exposed to fire.
  • Flexibility – The degree of movement a sealant can cope with when applied with a greater number meaning the sealant is more flexible.
  • Hybrid Polymers / MS – This is the next generation technology combining a sealant and adhesive into one product which can be used on most porous and non-porous materials giving them an almost unlimited number of application possibilities. One major advantage these products have over other sealants is that they can be applied in the wet and even under water.
  • Modulus – Sealants can be either high, mid or low modulus and refers to the elastic nature of the material.
  • Neutral Cure – Products which cure by a system of crosslinkers that, when activated by exposure to moisture in the air release almost odourless by-products, mainly alcohols. Neutral cure sealants have very little effect on the substrate applied to i.e. non-corrosive.
  • Oil Based Mastic – A traditional product mainly used in wooden window installations and pre-cast concrete panel sealing applications.
  • Polyurethanes – Combining the properties of a sealant, adhesive and filler into one product,
  • Shore A Hardness – A number which denotes the surface hardness of a sealant once cured. The higher the number, the harder the surface.
  • Silicone – The most common form of sealant on the market, silicones come is a variety of grades for multiple application uses.
  • Treated Articles – Some products now state ‘Please use treated articles responsibly’ within the health and safety panel which refers to any item which contains a preservative to protect the product though its life cycle.