What are sheet metal or “roofing” screws?

Material

Sheet metal screws are usually made from coated steel.

Application

These types of screws are designed to join timber or sheet metal to steel and are commonly used in roofing applications.

Characteristics

Head shape

Sheet metal screws have several different head shapes but the most common is the hexagonal washer head. 

Drive type

Sheet metal screws have different types of drives but the most common is the slotted drive. 

They can be inserted with a flat blade screwdriver bit, however, because of their hexagonal head, they can also be inserted using a socket. 

Body shape and tip

Sheet metal screws typically have a tapered body.

Some have a self-drilling tip which drills its own pilot hole before the thread starts to cut. Screws with self-drilling tips are often referred to as “Tek” screws. However, Tek is a brand name and should not be used as a generic term for these types of screws.

Threads

Sheet metal screws are usually fully-threaded but can have either fine or coarse threads.

How are they inserted?

When using sheet metal screws, you may need to drill a clearance hole or pilot hole first.