When selecting deck hardware, corrosion resistance from the exterior environment is required. Hot-dipped galvanized fasteners are quite popular, as they provide corrosion resistance at a reasonable price. However, be cautious in using galvanized products with lumber, such as cedar or redwood, as a chemical reaction with the resins in the wood causes black streaking. Stainless steel or proprietary coatings over steel are options for avoiding this condition.
Another consideration is to avoid contact of dissimilar metals. When differing metals are in contact in a wet environment, electrons are transferred between the metals resulting in corrosion. Copper content in most mainstream preservative treatments can create corrosion in hardware and fasteners if not carefully selected. Hot-dipped galvanized stainless steel or tested, proprietary-coated products must be used when adjacent to this lumber. Beyond this, it is also important for the hardware and fasteners that work together to be of the same material or otherwise not in contact.