What type of fastener is NOT allowed when working above grade or below grade on wood foundations?

Electrogalvanized steel fasteners are not allowed when working above grade or below grade on wood foundations due to their susceptibility to corrosion. Wood foundations are often subjected to moisture, which can lead to an environment conducive to rust and other forms of deterioration. Electrogalvanized steel fasteners, while coated to resist corrosion, typically do not offer the long-term durability required for applications in wet or damp environments compared to other materials.

In contrast, options like Type 304 stainless steel, silicon bronze, and copper are known for their excellent corrosion resistance. Type 304 stainless steel has a high nickel content, which enhances its ability to resist corrosive elements, making it suitable for wood foundations. Silicon bronze is also highly resistant to corrosion, especially in marine environments, and is often utilized in applications where metals will be exposed to water. Copper is inherently resistant to corrosion and has been used historically in various applications due to its durability and longevity. Therefore, the use of electrogalvanized steel fasteners is contraindicated in these situations, as they do not provide the necessary protection against corrosion to ensure the integrity of wood foundations.