Great news! For the first time, ICD High Performance Coatings will approve the use of OPACI-COAT-300® silicone spandrel coating, without requiring edge deletion (cutbacks), on qualified four-sided structural glazing (4SSG) applications*.

This development opens new design possibilities for architects, specifiers, and developers who previously had to choose between aesthetic flexibility and structural reliability. With standard tests showing ultimate tensile adhesion values averaging 152.15 psi across all required TA test conditions—over three times the required minimum—OPACI-COAT-300® delivers both performance and design freedom.

Performance Summary (ASTM C1135 – Tensile Adhesion)

Testing performed by two independent laboratories using UltraGlaze™ SSG4600 over both OPACI-COAT-300® #1-818 Black and #0-1060 Primary White – adhesion values are averages:

Combined ASTM C1135 Tensile Adhesion Results

Test Condition	Average Performance	Standard Requirement	Performance Margin
Standard Conditions (21-day cure)	132.05 psi	50 psi	164% above minimum
High Temperature (190°F)	151.35 psi	50 psi	203% above minimum
Low Temperature (-29°C)	175.35 psi	50 psi	251% above minimum
Water Immersion (7 days)	122.38 psi	50 psi	145% above minimum
5000 Hours QUV	179.6 psi	50 psi	259% above minimum

Additional observations and key takeaways from the performance data:

• Peak tensile stress values reached 235 psi
• Consistent 100% cohesive failure modes with most specimens
• 100% adhesion of OPACI-COAT-300® to the glass substrate with every specimen
• Exceptional performance retention across temperature extremes
• Impressive adhesion under extended water immersion

Why This Matters

Before now, due to insufficient adhesion performance data, four-sided structural glazing designs with OPACI-COAT-300® required edge deletion of the spandrel coating so the structural silicone was adhered directly to the glass. That requirement added more costly fabrication processes and may also have been aesthetically undesirable in the design.

That restriction is now lifted. With the remarkable test record outlined above, design teams now have verifiable tensile adhesion performance data to support specification of OPACI-COAT-300® for review and approval on their qualified projects*.

Design Freedom With OPACI-COAT-300® Delivered

Commercial Curtain Wall Systems

• Full four-sided structural glazing over opaque spandrel areas
• Seamless transitions between vision and spandrel areas for cleaner aesthetics

• Enhanced weather performance and thermal efficiency

High-Rise Façades

• Protected spandrel glass strength and improved resistance to breakage
• Improved structural load transfer across the building envelope
• Greater design consistency from ground to roofline

Standout Architectural Projects

• Construction initiatives promoting maximum ESG stewardship
• Complex geometries requiring structural glazing performance
• Projects where traditional mechanical fastening creates design conflicts

Approvals & Responsibilities (Who Approves What?)

Step 1. Design Team / Project Engineers: Responsible for total system engineering, design requirements, and code compliance.

Step 2. Structural Sealant Manufacturer: Must validate required mock-ups and project submittals, then issue final approval for sealant selection and use in the design.

Step 3. ICD High Performance Coatings: Will provide SSG-specific fabrication quality education and guidance. ICD will also validate the compatibility and adhesion performance of OPACI-COAT-300® on the substrate and issue a project-specific warranty on the coating when all approvals are verified.

Implementation Support

ICD offers a comprehensive technical services program, including project evaluation, custom compatibility and adhesion testing, fabrication guidance, and ongoing technical assistance for OPACI-COAT-300®. Written warranties apply only to OPACI-COAT-300® performance on the coated substrate, when fabricated per ICD requirements.

* Approval note: “Approved” or “qualified” applications or projects in this communication refers to ICD’s acceptance of OPACI-COAT-300® for consideration in 4SSG designs, contingent on approval of the complete structural glazing system by all contributing parties. Without exception, the structural sealant manufacturer must provide documented approval of the project. ICD does not approve, certify, or warrant the total system or the structural sealant.

Conclusion

The release of OPACI-COAT-300® for four-sided structural glazing applications represents more than a technical achievement—it's a design revolution. With performance margins well above industry standards and comprehensive support systems in place, this advancement opens new possibilities for architectural excellence.

Contact ICD High Performance Coatings today to discuss how this accomplishment can transform your next project. Our technical services team is ready to provide project support that gives you confidence to push design boundaries while maintaining structural integrity. For technical specifications, application guidelines, and project consultation, contact our technical services department at technicalservices@icdcoatings.com or call +1-360-546-2286.