Types of Screws

Find the best type of screw for your project

Types of Screws Image

While they may all look similar, different screws are designed for different uses. This guide will help you identify which screw is best to complete your project.

Anatomy of a Screw

A screw is simply a cylinder surrounded by ridges called threads. The top, the part that is visible after the screw is installed, is the head. Directly below the head lies the shank, a smooth area of the screw with no threading; not all screws have one. The rest of the cylinder is called the shaft. Screw height is measured from the end point of the screw shaft to the head.

Screws come in a number of different materials, including stainless steel, brass and aluminum, and can be covered with coatings such as zinc or black oxide that promote durability and ease of use with various materials.


Types Of Screw Heads

The screw head is where the force is applied. The various screw head types are designed to accept different driving instruments to distribute the force effectively.
 
The standard slotted head is best used with a flat screwdriver, while the cross-shaped indention is best suited to a Phillips screwdriver. A Robertson screw has a square-shaped indention and requires a matching driver head.

There are two types of hex screws: An Allen screw has a hexagonal indent in the head, requiring an Allen wrench, and the other type has no indent in the hexagonal head and must be applied or removed with a socket wrench.

While screw heads have evolved to include expanded and combined head designs, most drill bit sets come with multiple bits and bit guides to show you the head design that will suit the bit. Match the drill bit to the screw head size and design and you’ll have a much easier time attaching the fastener without stripping the head.


Common DIY Screw Types

There are five types of screws that the average DIY enthusiast will work with on a regular basis.

Screw Types Description Common Uses

Wood Screws

Coarse threads, smooth shank, tapered head 

Available in interior and exterior styles

Use for basic wood construction 

Choose a length that will penetrate the lowest board by 2/3 of its thickness 

Need a pilot hole drilled unless screw is self-tapping

Deck Screws

Similar to wood screws
 
Self-tapping 

Resists corrosion 

Head is designed to countersink

Use to attach decking to the deck frame 

Composite decking needs decking-rated screws

Drywall Screws

Self-tapping 

Head designed to countersink without damage to drywall 

Requires drywall dimple bit – not usually included in a standard drill set

Use for drywall installation only 

Standard screws for wood studs; metal studs need metal-rated screws

Masonry Screws

Tip is flat 

Most are hex-head design, some have Phillips head 

Also called an anchor

Must pre-drill holes prior to installation – requires hammer drill and masonry bit 

Anchor can be installed with a standard drill

MDF Screws

Self-tapping 

Star-drive heads

Require matching driver bits 

Designed to pierce without splitting material

Use with MDF material 

Avoids having to drill pilot holes


Other Types of Screws

Screw Types Description Common Uses

Torx/TORX Plus Screws

6-point star indention 

Requires TORX driver bits 

Design prevents screwdriver from slipping

Often used on electronics

Binding Screws

Two parts – male and female end 

Slightly domed head

Primarily used in bookbinding and leatherworking

Tamper-Resistant Screws

Variations on standard screws 

Special bits required to install and remove

Mainly used in public works to prevent vandalism and theft

Sheet metal screws

Sharp points, flat or hex washer heads 

Available in a range of sizes

Primarily used for metal – can be used to secure multiple materials together

Machine screws

Much stronger than standard screws 

Coated to resist rust 

Finer threads made more precisely

Used for joining machine parts

Lag bolt

Hex head 

Must drill a pilot hole to install 

Requires a ratchet

Used for joining metal to wood