4 Tips for Using Galvanized Nails with Pressure Treated Wood

It is important for any construction project to have a good understanding of the materials you are working with. When using galvanized nails with pressure-treated wood, it is also important to know how they will work with each other, as well as to choose the correct materials for the project at hand.

Tip 1 — Read Up on CCA, ACQ, CA Chemicals 

When wood is pressure-treated, a chemical preservative is forced into it, making it less prone to rot, as well as unappealing to insects and vermin. Until 2003, the most commonly used chemical to treat lumber was CCA (chromated copper arsenate). However, it was extremely toxic, and the industry has since voluntarily eliminated it for residential use. Other, less hazardous chemicals have replaced CCA and are commonly used to treat the lumber you will find at your local lumberyard. ACQ (amine copper quat) and CA (copper azone) are most readily found in pressure-treated wood to be used in most residential projects.

Tip 2 - EPA Recommendation

Existing decks and other projects constructed with CCA-treated wood pose no danger. But the EPA has recommended applying a penetrating oil finish to the wood, which will lessen, or even eliminate, the exposure to humans and pets. In any case, safety measures should be taken when handling pressure-treated wood, including the use of protective gloves, glasses, and masks. Pressure-treated wood is for outdoor projects only, so be sure to only work with it outdoors.

Tip 3 — Know Your Hardware

Everyday nails, screws, and fasteners are made of iron or steel, which are apt to rust due to time and exposure. The process of galvanization coats the hardware in a layer of zinc oxide. This protects the metal from rust and corrosion, while not diminishing its integrity. One particular galvanization process — electroplating, or electro-galvanization — puts a thin layer or zinc on the nail, leaving it with a smooth, shiny finish. However, hot-dipped galvanized nails have a much thicker zinc coating, which prevents corrosion better for a longer time.

Tip 4 — Match Your Materials to Your Project

Because of the thinner coating of zinc oxide on electro-galvanized nails, they are the better choice for indoor projects, where they will have little or no exposure to corrosive materials such as acids and chemicals, saltwater, or, for that matter, pressure-treated wood. For projects and constructions that will be outdoors or exposed to such conditions, hot-dipped galvanized nails should be used instead.

The acids and chemical preservatives used to treat lumber will eat away at the zinc coating on galvanized nails. Therefore, it is a general rule that the greater the exposure to corrosives, the thicker layer of zinc required on the hardware. Always keep this in mind when shopping for construction materials. When a project requires the use of pressure-treated wood, be sure to look for hot-dipped galvanized nails; look for “G185” on the hardware packaging, which will indicate the proper thickness of zinc oxide on the nails for use with pressure-treated wood.