Mastics come in which two bases?

• A. Solvent-based and Water-based
• B. Acrylic-based and Silicone-based
• C. Epoxy-based and Urethane-based
• D. Latex-based and Oil-based

Answer: (A)

Mastics are defined by the carrier or base that carries the resin and governs how they cure. The two main bases you’ll see are solvent-based and water-based.

Solvent-based mastics use organic solvents to dissolve the resin and carry it into place. As the solvents evaporate, the film forms. This type often offers strong adhesion and good performance in exterior or tougher conditions, but it tends to have higher VOCs and requires solvent cleanup.

Water-based mastics use water as the carrier. They dry as water leaves and the resin coalesces into a film. They’re generally lower in odor and VOCs and easier to clean up, making them popular for interior work, though their performance characteristics can differ from solvent-based types in terms of durability and weather resistance.

Other options refer to the type of polymer in the mastic (like acrylic or silicone) or older naming conventions, but the standard division to describe the base is solvent-based versus water-based.