General knowledge
- Terminology
- The goal
- Typical applications
- Common problems
- Critical factors for success
- Seal design
- Choice of materials
Sealants have been in use for hundreds of years. The Tower of Babel would have been built with mortar and tar or brai as sealing material. Bitumen and natural oil materials have been widely accepted as sealants for centuries.
Before the 1900s, mostsealants were derived from plant, animal or mineral substances. The development of modern polymer mastics coincided with the development of the polymer industry in the early 1930s.
- 1950’s – Polysulfide
- 1960s – Polyurethane
- 1970’s – Silicone
- 1990s – Silyle-ending Polyether (MS Polymer)
Terminology – Basics
What is the difference between a caulk and a caulking sealant?
A caulk is all composed of low or intermediate performance. In general, this is a lower quality and a limited lifespan. For example: acrylic latex, butyl, butyl rubber, copolymers, putty, etc.
Life cycle: usually 3 to 5 years.
A sealant usually refers to a high-performance compound with more expensive ingredients,
extreme weather and UV resistance and a long lifespan of 10, 20 to 30 years.
Relaxing under duress
It is the sealant’s ability to absorb the extension without additional stress on the substrate link line.
Sealants that recover completely and quickly from deformation generally have less relaxation of stresses than those that recover slowly.
- Low elasticity module sealer – Creates low stress on the sealant’s binding line. Generally has a greater ability to move.
- Medium module sealer – Typically a general purpose sealant that can be used for the majority of elastomer sealant applications.
- High module sealer – Not used for mobile seals, usually used for glazing applications.
Sealants for seals: Goals
Seal the crossings/joints between the building elements… a critical part of the building envelope.
- Some joints in motion, others immobile
Prevent water or moisture from seeping into the building or through joints or spaces.
- Preventing water damage
- Preventing corrosion of reinforced concrete
- Preventing structural damage to steel
- Help prevent mold development
Prevent hard materials or snow or ice from entering openings or joints… structural damage
- Accommodating the movement
- Function as part of an airtight system
- How it works as part of a steam-stopping system
- Acoustic control
Typical applications
High-rise and low-rise commercial buildings:
- Window perimeters
- Roofing endings
- Expansion joints and ends ends end
- Glazing
Main Channels (inclination) Outdoors
- HD, Target, Wal-Mart
Institutional
- Prisons and schools
- Airport tracks and traffic areas
- Seals for bridges and highways (DOT)
- Commercial parking and apartment work
Public works
- Sidewalks (concrete)
Park terraces
- Can be combined with a bridge system
Waste and water
- Submerged Environments (NSF)
Collage and collage applications
- Industrial, residential and commercial
Typical sealed products and building materials
- Concrete
- Masonry and brick
- Wood, plywood and cement-based cladding
- SIFE (Outdoor insulation and finishing systems)
- Stucco
- Stone, Manufactured Stone, CultureStone
- Vinyl and aluminum coatings
- Painted products
- Plastic foam panels
- Ceramic tiles
- Metal panels (coated and not coated)
- Systems include door caulkings, windows,and of course skylights.
Apps
Polyurethane seals like Sikaflex 1a or Sika 15 lm for the expansion of exterior facades and/or control joints between bricks…
Illustrate all these cases with photos p16 to 27
Sealing seals, common problems
Waterproofing products are probably the least taken into account and add the lowest percentage to the cost of a project but they can become the biggest problem if the building starts to leak.
There is science and art in the making of appropriate joints, from the design to the installation of the sealant.
Need to have:
- Proper seal design
- Appropriate product
- Correct application
Adhesion failure – when a sealant peels off the surface on which it has been applied.
- Poor surface preparation
- Wrong sealant for application
- Bad priming
Causes
- Poor surface preparation
- Contamination
- Wrong installation
- Bad priming
Remedies
- Grinding
- Proper cleaning
- A good priming
- Appropriate tooling
Common problems
Cohesion failure – tearing or cracking of the sealing putty in the middle. Usually, it stays glued to the sides of the joint. The reasons for the cohesive failure are:
- Excessive excess of sealant capacity
- Adhesion on all three sides
- Inadequate thickness of sealant to work in the joint
Coloring sensitive substrates (p40)
- The coloration is caused by fluids that have not reacted in the formulation of the sealant.
- Any sealant can stain if it is poorly formulated or used on an unremarkable substrate.
- Require an ASTM C-1248 colouring test and a spotless warranty from the sealant manufacturer.
Hoping to be useful to the technicians of you.
