Yes, aluminum strips can be used for outdoor decking or railings. They are known for their corrosion resistance, low maintenance, and durability, making them suitable for outdoor applications. Aluminum is lightweight, strong, and can withstand various weather conditions without rusting. However, it's essential to ensure that the aluminum is of high quality and properly treated to maintain its performance over time. Additionally, it's crucial to follow proper installation practices to ensure safety and longevity.