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Adhesives and Caulking

Topic 6 – Adhesives and Caulking

Adhesives

There is a wide variety of adhesives used to attach materials. The correct adhesive must be chosen based on a number of factors including material to be fastened, the base material, conditions such as temperature and moisture, as well as the method of attachment.

Glue

Used extensively in the carpentry trade, glue is extremely effective at bonding wood to wood and is also used in other applications. Glue comes in a variety of types:

– Polyvinyl Acetate (PVA) – Commonly known as white glue, it produces an exceptional wood to wood bond which is stronger than the wood itself. Can be manufactured to be resistant to moisture but should only be used in dry conditions unless otherwise specified.
– Aliphatic Resin – Known as yellow glue, it is thicker and not as runny as white glue, not recommended for moist conditions.
– Epoxy Glue – A two-part adhesive that is set by chemical reaction. Produces extremely high strengths and can be used in wet conditions.
– Contact Cement – Available as water and solvent based. Typically used to attach laminations to a base material. The adhesive is applied to both the laminate and substrate, allowed to dry, and then are pressed together to form an instant, permanent bond. While contact cement produces a strong bond, the strength of this adhesive is inadequate for most other applications.

Mastics

– Construction Adhesive – Used to provide a heavy duty and waterproof bond between building products such as wood, masonry, and concrete.
– Subfloor Adhesives – Used primarily in bonding sheet goods to floor structures, it can also be used in a variety of applications such and can also be used to bridge irregularities in framing members.
– Gypsum Board Adhesives – Used to adhere drywall to wood or steel studs to minimize the fastening required.
– Foamboard Adhesives – Primarily used to attach rigid insulation to a variety of materials. Should be chosen based on type as some adhesives will dissolve foam boards.

Caulking

Caulking is typically used to bridge and seal gaps between materials to prevent water infiltration and restrict air movement. When done correctly, it can vastly improve both performance and appearance. Caulking is available in a number of types, and the correct one must be chosen for each task.

Silicone – Long lasting sealant that is typically used to protect against water infiltration behind doors and windows, bathroom fixtures, and kitchen fixtures. One of the strongest adhesion, typically not paintable. Capable of lasting 12-30 years.

– Butyl – A rubber based caulking that is used in many exterior applications such as sealing gutters, siding, and roof vents. It is available in a variety of colours and lasts 8-10 years
– Acrylic Latex – often used in finish applications, does not last as long as silicone, especially in wet conditions. Is paintable and easy to clean up, and typically is paintable

Most caulking is available in a variety of colours to give an inconspicuous bead. If no colour match is available, it is recommended a paintable caulking be used. When applying caulking, it is important that the joint is prepared. Ensure that the gap is clean, free of dust, and dry. When replacing existing caulking, the old caulking must be completely removed. After applying caulking, the joint must be tooled. This can be accomplished with either a specific tool or by simply using a finger to produce a nice, rounded appearance.

Review Questions

  1. Most types of yellow and white glue should not be used in areas subject to _______.
  2. What is the most common use of contact cement?
  3. What can happen if the incorrect mastic is used to adhere rigid insulation?
  4. Which type of mastic can be used in cold weather?
  5. How can an overly large gap be prepared for caulking?
  6. What are the two drying times for caulking?

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Carpentry Refresher Program Manual Copyright © by Saskatchewan Indian Institute of Technologies-Trades and Industrial is licensed under a Creative Commons Attribution 4.0 International License, except where otherwise noted.