Drive screws that don't corrode. Silicon bronze. This material is the standard in marine fasteners because it resists corrosion and doesn't promote rot in the wood around the fastener. Stainless steel. Screws made of this material may cost twice as much as coated steel fasteners. The Golden Rule for outdoor fasteners..
Most rot-resistant pressure–treated lumber sold for homeowner use relies on two copper-based wood preservatives — alkaline copper quaternary and copper .
After 2004, all that changed with the phase out of CCA-treated lumber and the. . fasteners, connectors, or flashings in contact with pressure–treated wood.
Inside the lumberyard, you'd load up on nails, nuts, bolts, screws, and maybe joist. The copper in pressure–treated wood will eat through electroplated zinc .
According to tests designed and approved by the American Wood-Preservers' Association, the new treated lumber is more corrosive to fasteners than the old .