Drywall screws have become the standard fastener for securing full or partial sheets of drywall to wall studs or ceiling joists. Drywall screws’ lengths and gauges, thread types, heads, points, and composition at first might seem incomprehensible. But within the area of do-it-yourself home improvement, this vast range of choices narrows down to just a few well-defined picks that work within the limited types of uses encountered by most homeowners. Even having a good handle on just the three main features of drywall screws will help: drywall screw length, gauge, and thread.

• Drywall Screw Lengths
  1/4-inch drywall: Use 1-inch to 1 1/4-inch drywall screws
  • 1/2-inch drywall: Use 1 1/4-inch or 1 5/8-inch drywall screws
  • 5/8-inch drywall: Use 1 5/8-inch or 2-inch drywall screws
• Screws intended for construction generally range from 1 inch to 8 inches long. The reason is that building materials can have a wide range of thicknesses: from sheet metal to four-by-four posts and even thicker. Not so with drywall.
  Most drywall installed in homes is 1/2-inch thick. Thickness can sometimes increase or decrease, but only by very little and not very often. About the only time that do-it-yourselfers will need to install thicker drywall is with fire code or type-x drywall. At 5/8-inch, type-x drywall is slightly thicker to retard the spread of flames and is used in garages and walls adjacent to furnace rooms.
  Drywall that is 1/4-inch thick is sometimes used as facing for walls and ceilings. Because it is flexible, it can be used to form curves. Still, the majority of drywall installed by do-it-yourselfers in kitchens, bathrooms, and general areas will be 1/2-inch thick.