How Do Drywall Anchors Work and How to Install Them

Whenever you engage in a home improvement project, it almost always involves hanging new wall decorations. However, you can’t just drill them directly onto the wall, especially if your home is made of drywall — you’ll need a drywall anchor.

How do drywall anchors work? Simply put, a drywall anchor is an insert that will secure the screw against the drywall between the wall studs. They are typically made of plastic, steel, or zinc, each with different weight capacities.

Each type of drywall anchor has different holding powers and installation methods. For example, the size of the pilot hole (drilled hole), how much weight they can support, and so on. Knowing the differences is crucial because the incorrect installation method may cause your wall decorations to fall, leading to costly repairs and worse, harming someone.

Don’t worry, because this article will teach you everything you need to know about drywall anchors, including:

  • How do drywall anchors work
  • Types of drywall anchors
  • How to install wall anchors

How do drywall anchors work?

Drywalls (the wall panels in most homes) are made of gypsum and are only ½ inch thick. So, screws will fall off easily if installed without drywall anchors. This is because screws and drywall anchors on their own have weak holding power, making them unable to support paintings, bookshelves, mirrors, and other decorations. 

That’s where a drywall anchor comes in! Drywall anchors are metal or plastic inserts that serve as sleeves for screws. These wall anchors provide a secure insert and also increase the holding strength of a screw.

Generally, wall anchors work by first drilling a pilot hole into drywall. Then, you’ll insert the screws together with the anchors into the drywall.

Wall anchors are made of either plastic or metal, with each type differing in price and holding power. Regardless of their materials, different drywall anchors have distinct mechanisms to fasten the screws in place. For example, spring-loaded expands two metal flaps that secure the screw against the wall and prevent it from falling.

Do you need to use anchors in drywall?

Yes, you do need anchors when hanging fixtures on drywall. The main reason being drywalls are brittle and too weak to support fixtures on their own. However, you don’t need a drywall anchor when drilling a decoration against wall studs.

Wall studs are wooden frames that make up the skeleton of your home and are strong enough on their own to support wall fixtures. In fact, inserting wall anchors into wall studs will weaken its holding power. As a result, your photo frame (or whatever it is you’re hanging) may fall and cause a huge mess. 

Drywalls are made of gypsum and are only ½ inch thick. So, screws will fall off easily if installed without drywall anchors. A drywall anchor not only provides a secure insert but also increases the holding strength of a screw. 

Types of drywall anchors

 MaterialWeight ratingSuitable decorationsEasy to install?
Expansion drywall anchorsPlasticUp to 20 lbs.Small photo frames, clipboardsVery easy
Self-drilling drywall anchorsPlasticUp to 50 lbs.Small mirrors, photo framesEasy
Molly boltsMetalUp to 100 lbs.Medium-sized bookshelves, towel racks,Intermediate
Toggle boltsMetalUp to 200 lbs. Large mirrors, TVs, bookshelvesSlightly difficult

There are four common types of drywall anchors: expansion drywall anchors, self-drilling drywall anchors, molly bolts, and toggle bolts. Generally, expansion and self-drilling drywall anchors are more suitable for hanging lighter objects, whereas molly and toggle bolts are meant for heavy-duty applications. 

Expansion and self-drilling drywall anchors are also usually made of plastic, although some sellers do provide metal variations. On the other hand, molly and toggle bolts are made of metal and slightly more costly than plastic anchors.

Expansion drywall anchors

How do drywall anchors work? Expansion wall anchors work by extending its flaps to fasten the screw.

When you drive an expansion anchor into the drywall, they expand and push itself into the drywall. These are the most common drywall anchors that you’ll find packed together with photo frames. 

Expansion drywall anchors are affordable and easy to install. However, they’re designed to only hold lightweight objects between 5 to 20 pounds, depending on their size. This is because expansion anchors are made of plastic, which is less sturdy than metal drywall anchors. 

That said, some manufacturers do sell metal expansion wall anchors. Naturally, these metal anchors can have stronger holding power and can support heavier wall fixtures.

Weight rating: Expansion drywall anchors can hold up to 20 pounds, depending on their size. As their sizes can vary greatly, you should contact the seller for its specifications and weight capacity.

Best for: Picture frames, clipboards, and other light-duty applications. 

Self-drilling drywall anchors (threaded drywall anchors)

How do self-drilling drywall anchors work? They can be installed directly to drywall.

As its name suggests, self-drilling drywall anchors do not require pre-drilled pilot holes in drywall for installation. These anchors are threaded like screws that allow you to drive them into the drywall with a screwdriver. This makes them easy to use and less hassle to install than other wall anchors. 

Moreover, self-drilling anchors can hold more weight than expansion anchors. However, like expansion drywall anchors, these plastic anchors only have intermediate holding power are only meant for hanging lightweight objects

Weight rating: Generally, Self-drilling drywall anchors can hold up to 50 pounds. Some are made of metal and can hold more weight. Nonetheless, you should always check the brand’s specifications. 

Best for: Light to medium-duty applications such as small mirrors, photo frames, and small shelves. 

Molly bolts

Several metal molly bolts.

Also known as steel hollow-wall anchors, these metal anchors expand and create an anchor once inside the drywall. The molly bolt wraps the screw with a metal sleeve to secure it to the wall. Some brands of molly bolts even allow you to remove the screw from the sleeve.

Furthermore, molly bolts are one of the two types of drywall anchors that you can use in plaster walls. The reason is that molly bolts are made of metal rather than plastic, and thus have stronger holding power.

We recommend using either molly bolts or toggle bolts if you’re new to DIY home improvement projects. While they are slightly more expensive than plastic wall anchors, those few additional dollars spent will prevent broken decorations and costly injuries.

Weight rating: Can hold up to 100 pounds depending on brand and size. 

Best for: Medium to heavy-duty applications such as towel racks, bookshelves, and mirrors. 

Toggle bolts

Metal toggle bolts.

Toggle bolts are the strongest drywall anchors available. These metal anchors are designed to hang the heaviest of wall fixtures. However, they are the most difficult drywall anchor to install and also the most expensive out of the four wall anchors in this article.

A toggle bolt works by expanding its spring-loaded collapsible wings behind the drywall. The expanded anchors will fasten the toggle bolt to the entire sheet of drywall rather than one small area. This allows the toggle bolt to secure the screw and ensure that it doesn’t drop behind the drywall. 

Once secured into the drywall, you can’t remove the screw from the bolt. Like molly bolts, you can also install toggle bolts in plaster walls.

Despite being not as easy to install, toggle bolts have the highest holding power out of all wall anchors. This makes them suitable for supporting extremely heavy items such as television sets, large bookshelves, and mirrors. Some people also use toggle bolts for lighter objects to give them that extra reassurance. 

Weight rating: Can hold up to 300 pounds depending on brand and size.

Best for: Heavy-duty applications such as televisions and large shelves. 

How to install drywall anchors

Now that you’ve learned how do wall anchors work, it’s time to actually install them. Regardless of which drywall anchor you use for your home improvement project, ensure to follow the manufacturer’s specific instructions. Different wall anchors have varying specifications such as their pilot hole size, holding power, and so on.

Moreover, the same type of drywall anchors can differ in size, which will also affect their installation method. With that being said, drywall anchors are generally easy to install, even for home improvement greenhorns!

Read on to learn a general step-by-step guide on how to install the 4 different types of wall anchors. Again, always follow the manufacturer’s specific instructions, and don’t be shy to give them a call if you need help.

Expansion drywall anchors

You’ll need: Electric drill, screwdriver, hammer, screw. 

  1. Drill a pilot hole the same size as the expansion drywall anchor.
  2. With a hammer, tap the anchor into the drywall until it is flush against the wall.
  3. Using a screwdriver, insert the screw into the anchor.

Note: The screw head should be flush against the wall. 

Self-drilling drywall anchors

You’ll need: Screwdriver, screw. 

  1. With a screwdriver, insert the anchor by turning it clockwise against the wall. 
  2. Insert the screw into the anchor until it feels snug and flush against the wall.

Note: Sometimes, the tip of the drywall anchor will break off. This is completely normal and will not affect the performance of the anchor.

Video guide

Molly bolts

You’ll need: Electric drill, scr ewdriver drill bit.

  1. Insert the screw into the molly bolt’s sleeve. 
  2. Drill a pilot hole the same size as the molly bolt. 
  3. Insert the anchor into the drywall with your hand.
  4. Switch to a screwdriver bit and turn the screw clockwise for the anchor to expand behind the drywall. 
  5. Before installing other hardware or mounts, remove the screw by drilling it counter-clockwise. 
  6. Once done, drill in the screw back together with the mount. 

Video guide

Toggle bolts

You’ll need: Electric drill, screw washer.

  1. Drill a hole large enough for the anchor to fit through the drywall. 
  2. Insert the screw and washer into the toggle bolt with its flat side facing the screw head. 
  3. Press the toggle and insert through the hole. You should hear a ‘click’ sound as the anchor expands. 
  4. Drill the screw until its head is flush against the wall. At the same time, gently pull the bolt toward you to prevent the toggle from spinning.

Video guide

When NOT to use drywall anchors

When hanging fixtures directly against the wall studs

Drywall studs are wooden frames that support the structure of your home. You only need drywall anchors if you are drilling between wall studs, which are usually spaced 16 or 24 inches from each other. 

The reason is that wall studs provide more support than drywall anchors would. This is also why you should always try to mount heavy things against wall studs rather than drywall anchors. 

Against plaster or masonry walls

Drywall anchors are not designed to be installed in masonry (brick or concrete) walls. When hanging anything on brick or concrete walls, you should use masonry anchors rather than drywall anchors. Masonry anchors are thicker so that they don’t crumble in the wall. 

On the other hand, you should only use molly bolts and toggle bolts in plaster walls. Expansion and self-drilling drywall anchors will pull out easily from plaster walls. 

To hang fixtures that get touched often

Plastic drywall anchors will get loose when used to hang fixtures that get touched often. The primary example would be toiler paper holders. Instead, you should use toggle bolts or other metal anchors for fixtures that are frequently used.  

Without mounts for heavier fixtures

You should only use toggle bolts for hanging heavy fixtures between wall studs. TVs, large mirrors, floating cabinets, you know the drill. Moreover, always try to use mounting plates or mount brackets to bridge the studs. 

These mounting plates and brackets will provide much more support than any drywall anchor would by itself. You can also paint wooden mounting plates to match the color of the wall. 

Key takeaways

There are four common types of drywall anchors: expansion drywall anchors, self-drilling drywall anchors, toggle bolts, and molly bolts. Toggle and molly bolts are suitable for heavy-duty applications whereas expansion and self-drilling drywall anchors are more suited for light-duty applications. Moreover, you can’t use drywall anchors in concrete or brick walls. 

We hope you’ve gained a better understanding of how do wall anchors work. Which drywall anchor have you used before in your home improvement project? Let us know in the comments below!

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