How to put up something heavy on plasterboard

I purchased a large, heavy shelf and was planning to put it up on an interior, hollow wall. Realising that I really needed to make sure it wouldn’t come down because, if it did, it would land on my bed and cause serious damage to my partner and I if it happened at night. I also didn’t want to have to pay a tradesman to come and put up my shelf for me. That would be expensive- potentially costing more than the shelf! So I did a little research on how to put up something heavy on plasterboard.

When fixing something heavy like a shelf or a mirror to plasterboard, the key is to use the right type of wall plug / fixing. That is a specialised wall plug for hollow walls that can bear heavy loads. Standard wall plugs are designed for walls where they can embed into masonry and hence they aren’t suitable for most interior walls which are made with just plasterboard and timber. There exists a range of specialised fixings designed for plasterboard available from DIY stores.

The hollow wall anchor, aka the “Molly” wall fixing or expansion wall plug

My favourite wall plug to use when fixing items to plasterboard is the hollow wall anchor, also known as the “Molly” wall fixing or expansion wall plug. I have used these wall plugs many times over and they have never let me down. The way they work is they expand inside the wall cavity. They come in a variety of sizes, depending on the weight of whatever you’re putting up, and can bear weights up to 50kg. I would recommend purchasing a set that comes with a setting tool.

Tools you will need:

  • Hollow wall anchors
  • Hollow wall anchor setting tool
  • Drill
  • Screwdriver
  • Wire detector

Step 1

Position whatever you are putting up on the wall and mark with a pencil the points where you will drill holes, using a spirit level if required, for example when putting up shelf brackets.

Important: use a wire detector to ensure you won’t be drilling into live electrical wires!

Step 2

Look carefully at the wall plugs you are going to be using (the larger ones can bear more weight) and select the drill bit that is the appropriate size. The packaging of the wall plugs might even tell you what size drill bit to use. If in doubt, select a drill bit that is slightly too small rather than too large because you can always move the drill around slightly to create a bigger hole. However, you really don’t want a hole that is too big for your wall plug. Drill your holes ensuring your drill is set to the drill mode, rather than hammer-drill mode (since the latter is for drilling into masonry).

Be safe: wear eye goggles and a mask because plasterboard dust is very fine and should not be inhaled.

Step 3

The hollow wall anchors come with the screw inside, do not remove it. Push your hollow wall anchors into the holes you have drilled. You can give them a gentle tap with a hammer if they are not going in easily but if it’s not going in at all you will probably need to drill a larger hole by gently moving the drill around in the existing hole. The lip of the hollow wall plugs has small teeth that should bed a little into the wall. Next, take a screwdriver and unscrew the screw a little way (enough so you can get purchase on it with the level tool).

Next, place the screw head in the specialist setting tool that comes with the wall plugs. Press down on the lever which will begin to pull the screw out from the wall plug, expanding the wall plug within the wall at the same time. Usually, it’s not possible to continue to press down on the lever more than three times. You should be able to feel that the wall plug has expanding and is now firmly secured inside the wall.

Step 4

Use your screwdriver to remove the screw fully from the wall plug and place your shelf bracket into position. Screw the wall bracket into the hollow wall anchor tightly. If handing a mirror or artwork, don’t put your screw all the way in- you will need to leave a few millimetres of the screw unscrewed for your hanging wire.

Not feeling confident enough yet to try the above? Or perhaps never used a drill before? No problem! Find yourself a local DIY class- you’re never too old to start learning DIY skills and it could save you hundreds of pounds over the years. The Goodlife Centre runs a range of DIY classes in London. I’ve been on a couple and would highly recommend them!