From left, stainless steel, hotdipped galvanized mechanically galvanized and electroplated galvanized. fasteners. There are newer types of fastener coatings on the market, but we haven't extensively evaluated their longevity. It's important to remember that aluminum fasteners can be used for fastening untreated wood but that aluminum can rapidly corrode in wood treated with preservatives containing copper. Make sure your galvanized fasteners wear a heavy coat�CGalvanized coatings protect the steel underneath, so when the coating is gone. the underlying steel corrodes. That makes the thickness of this protective coating critical. wood plastic composite price in indiaTo galvanize fasteners. manufacturers apply coatings of zinc. cadmium or zinc/cadmium by electroplating, mechanical plating, chemically treating or hot dipping (dunking the fastener in molten zinc).

The thickness of these coatings varies significantly: hot-dipped coatings are typically the thickest and in our experience give the best corrosion resistance. Unfortunately, many builders use electroplated nails for outdoor construction because they are available for use in nail guns. Our research found that electroplated nails don't last as long as hot-dipped galvanized nails (top photo). In addition to nails, there are lots of hangers, post supports, hidden deck-board fasteners and other metal hardware available for use in deck construction. Just as with nails, screws and bolts, metal deck hardware should have a thick. durable, protective coating. Despite the cost, stainless steel is a bargain�CStainiess-steel nails, bolts and screws can cost many times what conventional fasteners cost. but considering the overall investment of lumber and time put into a deck. they're worth the price. especially in wet or salty environments. Our research shows that even after years of severe exposure, stainless steel holds up well. The problem with stainless steel is tithe metal is softer and more difficult to drive than carbon steel, which may result in more waste from bent nails or damaged screw heads. Avoid smooth-shank nails, and avoid nail pop-up�CAfter years of getting wet and drymg out, smooth-shank box and common nails can lose their withdrawal resistance. pop up and loosen connections.wood plastic composite market especially if they're used to secure deck boards (bottom photo). So for deckboards, we recommend deformed-shank nails, such as spiral-groove and ring-shank nails, or screws. These deformed-shank nails resist withdrawal effects from cupping and from wetting-and-drying cycles. Pop-up can also occur when nails are too short.

We recommend the use of at least 3-in. long nails (10d) to secure 1-in. thick deck Drawing this page: Dan Thornton 6 3 Lag screws need to be long enough so that at least half of their length penetrates the thicker member. A fiat washer should be used under the head. but not tightened so much that it crushes the wood. Bolts are more rigid and typically stronger than lag screws. Just remember to drill the pilot hole Use lag screws where bolts can't go�CFor fastening a 2x to a thicker member where a through bolt won't work, lag screws work well. Just remember that pilot holes should be 60% to 70% of the diameter of the threaded portion of the screw. Therefore, a 3 /8 -in. dia. lag screw would get a 1 /4 -in. pilot hole for the threaded portion. followed by a 3 /8 -in. pilot hole for the unthreaded portion. boards and 31 /2 -in. used vinyl fence for sale long nails (16d) for thicker deckboards. Screws�Cespecially drywall-type or bugle-head "multipurpose" screws-seem to have found a niche in deck building, too. Like other metal fasteners. screws used outside must be able to withstand the wetting-and-drying cycles that can cause weakening of metal and loosening of connections.