Last edited 03 Jul 2017

Mastic sealant

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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.

The most common types of material that mastic sealant can be adhered to include timber, aluminium, steel, marble, glass and various types of board, although it can be used on nearly all materials.

Examples of uses for mastic sealant include:

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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