Tech Tip: Which Screw Should I Use?

Selecting the best fastener for any decking job requires answering just three easy questions: What decking material will be used, Will the deck be exposed to a corrosive environment, and 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 galvanized steel, 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 screws are strong enough that #8’s are adequate for most applications, while the softer Stainless Steel normally requires a #10 screw. If you are in an area experiencing extreme weather conditions, or 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 2 by 4’s or 6’s require a 3” long fastener, while 5/4 by 4’s or 6’s only require a 2-1/2” long fastener. With rare exception, it’s that simple.
The following table lists fasteners commonly used for decking applications:
| Pressure Treated (ACQ) or Composite (Trex®) Wood |
| 1023-FP5, 1027-FP5 |
ProMax Stainless Steel Auger Point (Self-Drill) |
| 1024-FA5, 1030-FA5 |
Type 305 Stainless Auger Point (Self-Drill) |
| 0823-FPT, 0827-FPT |
ProMax NoCoRode “Plus” Dekkers (Self-Drill) |
| 0824-FCT, 0830-FCT |
NoCoRode “Plus” Standard Point |
| Trex®, TimberTech®, Fiberon®, Boardwalk®, Composite Lumber |
| 1024-DXT, 1030-DXT |
Stainless Double-DekkerTM Trim Head Composite Lumber Screw |
| 1024-DDS, 1030-DDS |
Stainless Double-DekkerTM Composite Lumber Screw |
| 1024-DDG, 1024-DDT |
Double-DekkerTM Composite Lumber Screw |
| 1030-DDG, 1030-DDT |
Double-DekkerTM Composite Lumber Screw |
| (Double-Dekkers are not designed for use in natural wood products) |
| Western Red Cedar, Redwood, Teak, Ipe, Pau Lope® |
| 1023-FP5, 1027-FP5 |
ProMax Stainless Steel Auger Point (Self-Drill) |
| 1024-FA5, 1030-FA5 |
Type 305 Stainless Auger Point (Self-Drill) |
| 1024-HFB, 1030-HFB |
Type 305 Stainless HeadCote Auger Point Painted Head |
| Seaside Applications |
| 1024-SD6, 1030-SD6 |
Type 316 Stainless for Seaside Docks |
| 1024-FA5, 1030-FA5 |
Type 305 Stainless for Inland Decks |
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| ProMax® is a registered trademark of McFeely’s Square Drive Screws |