Architects and specifiers rely on ASTM C920 to ensure that a sealant will accommodate expected building movement, adhere to common substrates (concrete, glass, aluminum, etc.), and maintain a weathertight seal over a typical service life of 5–20 years, depending on the application.
This standard does not cover structural glazing sealants (see ASTM C1184) or fire-rated sealants (see ASTM C919). It also does not guarantee compatibility with all substrates or primers. Architects and specifiers rely on ASTM C920 to
Scope: ASTM C920 establishes the minimum performance requirements for cold-applied, elastomeric joint sealants used in building and civil engineering applications (e.g., curtain walls, pavement joints, window perimeters). adhere to common substrates (concrete