HS Code for Mastic sealant

Mastic sealants are classified under HS code 3214.90. Chapter 32 covers tanning or dyeing extracts, tannins and their derivatives, dyes, pigments, and other coloring matter, as well as paints and varnishes, putty, and other mastics. Heading 3214 includes glazier's putty, grafting putty, resin cements, caulking compounds, and other mastics, as well as painters' fillings and non-refractory surfacing preparations for facades, indoor walls, floors, ceilings, or the like. Subheading 3214.90 is the residual category for "other" mastics and fillings that are not specifically resin cements or glazier's putty. These products are typically used to seal joints, cracks, or gaps to prevent the passage of air, water, or other substances. They are characterized by their ability to remain somewhat flexible after application. The classification depends on the chemical composition and the intended application as a filler or sealant rather than a pure adhesive. Under GRI 1, the product is classified based on its function as a mastic or filling preparation. These products are often based on plastics, rubber, or bitumen, but their classification in 3214 is determined by their use in construction and repair for sealing purposes.

Products Included

• Silicone sealants and caulks
• Acrylic joint fillers
• Polyurethane sealants
• Bituminous mastics for roofing
• Non-refractory surfacing preparations
• Plaster-based painters' fillings

Common Misclassification

Mastic sealants are frequently misclassified under 3506.91, which covers adhesives based on polymers. While some sealants have adhesive properties, their primary function in heading 3214 is to fill gaps or seal joints. Another common error is using 3214.10, which is specifically for glazier's putty, grafting putty, and resin cements. If the product is a modern synthetic sealant used for general construction, 3214.90 is usually the more appropriate code. It is also sometimes confused with 3824.99 for miscellaneous chemical products, but 3214 is more specific for mastics.

FAQ

What is the HS code for mastic sealant?

The HS code for mastic sealant is 3214.90, covering other mastics and painters' fillings.

Is silicone caulk classified as an adhesive?

While it has adhesive properties, silicone caulk used for sealing is primarily classified under 3214.90 as a mastic rather than under 3506 as an adhesive.