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Mastic is commonly used on construction projects as an adhesive and sealant. It is a popular choice where one surface needs to be adhered to another in a durable bond, or where the area needs to be protected.
Examples of uses for mastic sealant include:
- Bonding ceiling, wall and floor tiles.
- Bonding plywood panels.
- As a joint-sealer for windows and doors.
- Sealing the area around bathtubs and other sanitary appliances.
- As a filler for cracks in masonry and concrete.
Mastic can be used outside because of its water-resistant, temperature-resistant and UV-resistant properties. It is also capable of resisting corrosion which makes it suitable for use with metals.
Although mastic will usually resist some applied pressure, it is not flexible enough to accommodate large movements. Due to its viscosity, it is best applied to thick rather than thinner areas of application, such as large gaps and cracks. Before applying mastic, the area may not require priming, but it should be clean and dry. It is best applied by using a caulking gun.
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