Introduction: Hanging Heavy Mirror on Plaster Walls

About: DIY Montreal is all about woodworking & DIY projects. I post how-to videos on my YouTube channel, as well as step-by-step tutorials on my website Builds include mainly woodshop project…

In this short tutorial, I'll show you how to hang a heavy mirror on plaster walls. Hanging heavy objects on the wall can be tricky, and with all the options available out there, downright confusing. Even more so if you live in an old house with plaster and lath walls.

If you can hang your heavy object in line with a stud and screw a long screw directly into the stud, that's always the best option.

Step 1: Use a Molly Bolt

One foolproof method to hang heavy mirrors or picture frames is to use a molly bolt. This hollow wall anchor will allow you to hang your frame anywhere, without having to find a stud.

Using Molly bolts is really simple. Here are the basic tool you'll need:

Step 2: Draw Horizontal Line

I like to start by placing a piece of painter’s tape on the wall, close to where my hanging screws will need to go. Next, I use a level to draw a horizontal line on the tape.

Step 3: Measure & Mark

The mirror I’m hanging has 2 keyhole slots, so I started by measuring the distance from center to center.

I then transferred that measurement onto my line, making 2 marks.

Tip: It’s best to use a hard ruler rather than a tape measure for greater accuracy.

Step 4: Drill the Holes

You’ll want to use a drill bit that’s slightly smaller than the size of the molly bolt you have. You want to be able to easily tap it in with a hammer, but not have it floating around in the hole.

Remove the tape, then lightly tap in the molly bolt, all the way in, so the “hooks” bite into the wall.

Step 5: Expand the Anchor Wings

Using a screwdriver, turn the screw clockwise several times until you feel moderate to strong resistance. This will expand the anchor wings behind the wall and anchor the fastener into place.

To see how a molly bolt works and see what happens behind the wall, check out this short video.

Next, back out the screw a few turns so it sticks out of the wall slightly.

Step 6: Hang Mirror

Now all that’s left is to hang the mirror on the screws. Easier said than done, but eventually you line up the holes just right and it slides into place.


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