Astm C920 Standard Specification For Elastomeric Joint Sealants Summary _verified_ -

The standard provides a universal classification system—Type, Grade, Class, and Use—to help architects and contractors select the right product for specific applications like curtain walls, plaza decks, or window perimeters.

: Self-leveling; used for horizontal joints like floor slabs. : Evaluates the sealant's ability to maintain adhesion

Durable enough for pedestrian or vehicular traffic areas like plazas or walkways. The purpose of this standard is to ensure

: Evaluates the sealant's ability to maintain adhesion and cohesion during repeated expansion and contraction. and Use (e.g.

The ASTM C920 standard specification covers the requirements for elastomeric joint sealants used in building construction. The standard is applicable to sealants that are used to fill joints and gaps in substrates, such as concrete, masonry, and metal. The purpose of this standard is to ensure that elastomeric joint sealants meet minimum performance requirements for durability, adhesion, and resistance to weathering and aging.

Certified sealants must be labeled with the ASTM C920 designation, including Grade, Class, Type, and Use (e.g., ASTM C920, Grade NS, Class 25, Type S, Use NT ).