A Technical Note by ECOIN INSULATION
Overview
Aluminum jacketing is valued for its durability and corrosion resistance; however, surface discoloration may occur due to oxidation when exposed to moisture during transportation, handling, or storage.
Cause of Surface Oxidation
Surface discoloration/oxidation is a superficial condition caused by prolonged contact between moisture and the aluminum surface, often resulting from condensation or trapped humidity. This condition typically occurs prior to installation and is influenced by temperature fluctuations, high humidity, and limited airflow.
Material Analysis and Test Results
We conducted material analysis on affected areas in a Canada lab, Element-Cambridge.The relevant excerpt from the laboratory report is provided below. The full report is available upon request.
- Compositional analysis of the affected regions revealed elevated oxygen content, confirming that the surface condition is primarily associated with the formation of aluminum oxide. The oxidized areas exhibited particulate features, in some cases
with a cracked, “dry mud” appearance, indicating prior contact with water that subsequently dried.
- The oxidation was found to be very superficial in nature and did not affect the integrity of the aluminum rolls.
- Cross-sectional examination showed no metallurgical discontinuities or internal flaws in the aluminum material.
Impact on Performance
While surface oxidation may affect appearance, it does not compromise the physical strength, structural integrity, or protective performance of the aluminum jacketing. The condition is cosmetic in nature and does not indicate a defect in material quality.
Storage and Handling Recommendations
- Store aluminum jacketing indoors, under cover, in dry and well-ventilated areas
- Minimize exposure to moisture and temperature cycling during storage and transport
- Allow aluminum to acclimate gradually when moving between different temperature environments
- Inspect material prior to installation
Conclusion
Surface oxidation and discoloration are known and well-understood characteristics of aluminum when exposed to moisture under certain conditions. Based on industry knowledge and our laboratory testing, this condition is cosmetic only and does not affect the overall composition, structure, or performance of the aluminum jacketing.