Use Stainless Steel Nails When Building a Deck

I also used the same technique on the rim joists to dress up the deck skirt. Basically I wrapped Mahogany deck lumber over the deck skirt’s 2×8 lumber to dress up the sides of the deck, and again I tacked the Mahogany deck boards to the rim joists using my nail gun and galvanized finish nails. Afterwards, I went back and used stainless steel nails to hold the boards permanently in place.

The deck looked great for about 3 months. Then I began to notice dark stain patterns forming on the deck surface and dark streak stains along the deck skirt. After a close inspection I determined that the dark stains were occurring from the galvanized finish nails that I had used. They were oxidizing and corroding and in the process producing a dark stain on the deck surface. I sanded the deck surface and then applied a coat of water sealer to help retard the oxidation and corrosion of the finished nails. This helped for awhile, but within a year the stains were back.

I still have the deck, along with all its warts, however I plan to finally replace the Mahogany deck boards soon. This time, however, I am going to go with composite decking boards and forgo the use of galvanized nails or fasteners of any type. In my opinion and experience, always use stainless steel nails when building a deck.

If you want to prevent this type of deck construction mistake, and many others, see my Deck Installation Bid Sheet. It captures all of the “watch out fors” when either building your own deck or hiring a deck building contractor.