Which Screw Should I Use?

Which Screw Should I Use?

Selecting the best fastener for any decking job requires answering just three easy questions:

  1. What decking material will be used?
  2. Will the deck be exposed to a corrosive environment?
  3. Finally, how thick is the decking material?

The choice of fastener material is dictated by both the decking material and the environment. Galvanized screws work well with pressure-treated decking, while Redwood or Western Red Cedar decks are usually built with stainless steel screws to prevent staining around the screw heads. The new man-made decking materials, such as Trex® polymer wood, can be fastened with either galvanizedsteel, ceramic-coated or stainless steel screws. Tropical wood decking, such as Ipe, Pau Lope™ or Teak, is generally fastened with stainless steel screws for virtually a lifetime of maintenance-free service. The corrosive atmosphere of a seaside location dictates a minimum of type 305 stainless steel fasteners, regardless of the decking material used. Docks, because of their more severe service requirements, should be built with type 316 stainless steel screws.

Screw material also dictates the screw gauge required. Our hardened-steel NoCoRode Plus screws are strong enough that #8s are adequate for most applications, while the softer stainless steel normally requires a #10 screw. If you are in an area that experiences extreme weather conditions or if the structure may experience unusual loads, consult a Licensed Professional Engineer for design assistance. Fastener length is easiest to determine, since it is governed by the thickness of the decking itself. Standard 2x4s or 2x6s require a 3 in. L fastener, while 5/4x4s or 5/4x6s only require a 2-1/2 in. L fastener. With rare exceptions, it’s that simple.

Deck Fasteners