What are galvanized self-tapping screws and how to fix them?

Self-tapping screw is an abbreviation for "self-tapping screw". The main difference from other fasteners is that there is no need for a pre-drilled hole.

The key advantage of galvanized self-tapping screws is moisture resistance. This type of fastening is practically resistant to rust. Zinc prevents corrosion by taking the full blow. The strength of the self-tapping screw depends on the thickness of the zinc layer. Galvanized self-tapping screws are used in the fastening process. In appearance, they are no different from ordinary metal rods. They provide a strong grip due to the triangular thread.

There are several types of self-tapping screws, each of which has its own purpose.

• Universal - self-tapping screws suitable for any occasion. They can be used on metal, wood and plastic. The key difference is the variety of shades.
• With a press washer. Mainly used for metal profiles. A characteristic detail is a wide head, with the help of which sheets of metal and thin strips of wood are reliably pressed.
• For a tree. They differ from others with threads with turns at a great distance from each other.
• For metal. They have a tip in the form of a drill and a cap in the form of a cone. When working, they do not require separate surface drilling. Due to the cone-shaped head, the most reliable fastening is obtained.
• For the roof. In addition to the cone-shaped tip and the hexagonal cap, there is a rubber layer that not only serves as an additional seal, but also prevents moisture from leaking under the roof. They are also available in a variety of colors.
• For furniture. Distinctive features are a sawn-off tip and a hat with a recess.
• Hexagons. Self-tapping screws resembling standard bolts, but with special threads and a pointed tip. Their main task is to hold large elements. They are suitable for working with wood as well as concrete using dowels.
• Anti-vandal. This is a universal type of self-tapping screws used for various materials, depending on the thread. Their feature is a uniquely shaped slotted hat that cannot be unscrewed with a regular screwdriver.

The size of self-tapping screws is determined by two parameters: length and diameter.

The length of the product is selected depending on the thickness of the fastened elements. For example, to fasten one sheet of drywall with a thickness of 12 millimeters, use a self-tapping screw with a diameter of 3.5 mm and a length of 25 mm, and if necessary through-mounting, self-tapping screws with a length of 180 mm are used. In practice, builders do not purchase one screw at a time, but in packages. For example, a 5x45 package in the amount of 5000 pieces weighs 3.42 kg.

When installing the roof, the fasteners are screwed into the lower wave for a secure fit of the metal. Only a high ridge is attached through the "wave crest" with the appropriate self-tapping screw. Experienced builders recommend using 6 to 8 bindings per square meter.