Sealants That Meet Both ASTM and ISO Standards

In regulated construction markets, product compliance isn’t just about local building codes—it’s about international performance verification. Sealants used in joints, gaps, penetrations, or weatherproofing applications must often meet both ASTM (American Society for Testing and Materials) and ISO (International Organization for Standardization) standards to be approved for use in healthcare, education, transportation, and global corporate facilities.

For architects, contractors, and procurement managers, specifying sealants that meet both ASTM and ISO standards helps ensure long-term durability, code acceptance, and liability protection. At Buldix BuildMaterialsDistribution.ai, we offer a full range of elastomeric, hybrid, and silicone sealants with dual-certification and full traceability for demanding project environments.

Why Dual-Certified Sealants Matter

Global project compliance: Multinational developers and architects often require ISO-certified products to meet overseas standards, while AHJs in the US and Canada still require ASTM testing.

Improved quality assurance: Products tested to both standards undergo broader scrutiny, including mechanical performance, aging resistance, and substrate compatibility.

Specification flexibility: When specs cite both ASTM C920 and ISO 11600 or ISO 9046, dual-compliant sealants help streamline submittals and avoid substitution delays.

Liability mitigation: Dual-tested products reduce the risk of failure claims, warranty disputes, or insurance complications tied to non-compliant material use.

Key ASTM Standards for Sealants

ASTM C920: Standard specification for elastomeric joint sealants. Defines sealant types, uses, and performance categories (Class 25, 50, 100/50).

ASTM C719: Measures adhesion and cohesion under cyclic movement—used to define movement class (e.g., ±25%, ±50%).

ASTM C1246: Assesses visual contamination of sealant on adjacent substrates.

ASTM C1382 / C794: Bond strength, adhesion-in-peel, and pull-off testing for sealant performance over time.

Key ISO Standards for Sealants

ISO 11600: Defines movement capability, hardness, and adhesion of building construction sealants. Split into F (facade) and G (glazing) types, with subcategories based on modulus and movement class.

ISO 9046: Water tightness performance of sealant systems.

ISO 10563: Measures sealant volume loss during cure.

ISO 8340: Evaluates sealant performance under movement stress.

Types of Sealants Commonly Dual-Certified

Silicone Sealants (Neutral Cure and Acetoxy)

Ideal for curtain walls, glazing, and exterior expansion joints.

Excellent UV, ozone, and moisture resistance; low modulus versions often rated Class 50+ in both ASTM and ISO.

Polyurethane Sealants

Strong adhesion to concrete, masonry, and metal—used in horizontal joints, control joints, and parapets.

Typically meets ASTM C920 Class 25 and ISO 11600-F-25HM or F-25LM.

Silyl-Terminated Polyether / Hybrid Sealants

Combine silicone elasticity with polyurethane adhesion.

Common in green buildings due to low VOC and high movement capacity; often ISO 11600 F-25LM compliant and ASTM C920 Class 25/50 rated.

Acrylic Sealants (Water-Based)

Used for interior trim, drywall, or low-movement joints.

Limited to Class 12.5 or less—usually ISO-only or ASTM C834 rated for residential or cosmetic applications.

Ideal Use Cases for ASTM + ISO Sealants

Healthcare and Lab Facilities

Sealants in these settings must resist cleaning agents and provide clean joints—ISO 11600 testing ensures compatibility with disinfection protocols, while ASTM C920 validates movement capacity in large panel assemblies.

Curtain Wall and Façade Glazing

Requires Class 50/100 sealants with UV resistance, adhesion, and joint flexibility. Look for ASTM C920 Class 50/100 and ISO 11600 G-25LM/G-50HM certification.

Transportation Infrastructure

Joint sealants in airports, transit hubs, and bridges require resistance to vibration, moisture, and movement—products meeting both standards provide peace of mind in demanding conditions.

Data Centers and Tech Campuses

Mission-critical environments require reliable air and water seals—dual-certified sealants meet LEED, WELL, and performance documentation for global tenant buildouts.

Submittal and Compliance Tips

Always include current TDS and SDS: Many dual-certified products are updated regularly—ensure you have the latest version.

Request test certificates by batch: For government or institutional projects, documentation often requires batch-specific test results.

Check movement class equivalency: ASTM C920 ±50% may align with ISO 11600 F-25LM or G-25LM depending on modulus.

Watch VOC content: Ensure sealant complies with South Coast AQMD Rule 1168 and is compatible with indoor air quality certifications.

Why Buldix for Dual-Certified Sealants

Buldix BuildMaterialsDistribution.ai supplies a full spectrum of joint sealants tested to both ASTM and ISO benchmarks. Whether you need silicone for curtain wall glazing, hybrid sealants for precast concrete, or fire-rated perimeter sealants for code-sensitive buildings, we’ve got the documentation, batch traceability, and inventory to support complex specs.

We assist contractors, architects, and facility owners in matching sealant systems to climate, movement, and compatibility requirements. Our technical team helps review UL assemblies, mock-up protocols, and third-party certifications to keep your job on schedule and inspection-ready.