Drywall Anchors Explained: How They Work & When to Use Them

Screws are the go‑to fasteners for hanging shelves, coats, mirrors, pictures, and more. However, when the backing material is drywall, a screw alone may not hold up under weight or stress. That’s where drywall anchors—also called drywall plugs—come into play. They’re hollow, self‑expanding inserts that create a robust interface between the screw and the wall.

What Exactly Are Drywall Anchors?

Drywall anchors are engineered to grip drywall panels securely. Constructed from durable plastic or engineered polymers, each anchor has a hollow core designed to accept a screw. When the screw is driven in, the anchor expands against the inside of the drywall, distributing load and preventing the screw from pulling out.

How Do Drywall Anchors Work?

Unlike a standard screw that goes straight into the wall, a drywall anchor first needs a pilot hole. After drilling the hole, you push the anchor into place. When you thread a screw into the anchor, the anchor’s back expands like a tiny clamp around the drywall’s backside, creating a solid anchor point. This expansion allows the screw to support heavier loads than it could in drywall alone.

When Should You Use Drywall Anchors?

Drywall anchors aren’t necessary if you’re attaching something to a stud. In North America, studs are typically spaced 16 to 24 inches apart, so you can usually find a stud within that range. When a stud isn’t available—or if you need to hang an item that exceeds the screw’s weight rating—a drywall anchor is essential. Common scenarios include:

• Hanging medium‑to‑heavy pictures or frames
• Installing shelves or brackets that support weight
• Securing coat racks, mirrors, or other wall décor
• Attaching fixtures in rooms with limited stud placement

Choosing the right type of anchor (e.g., plastic expansion, toggle, or molly) depends on the load and wall condition. For most residential projects, a standard plastic anchor will suffice, but for heavier items, a toggle or molly anchor provides superior holding power.