How to Screw into Drywall: Suitable Wall Plugs and Maximum Loads
An ordinary wall plug in a plasterboard sheet always ends up tearing out. To fix a cabinet or a screen to drywall, you need special hollow-wall anchors, capable of spreading the load behind the sheet.
How drywall works
A standard plasterboard sheet (13 mm) has little tensile strength: a screw driven into it tears out under load. The special anchors open up behind the sheet (expanding anchors or Molly bolts) to press against a large surface and support far greater loads.
The types of drywall anchors
- Expanding anchor (butterfly): opens up behind the sheet, load up to 30 kg
- Molly bolt: screw-in, opens up behind the sheet, load up to 40 kg
- Spring toggle anchor: ideal for very thin sheets, presses flat behind
- Direct screw-in anchor: low load (up to 5-8 kg), for light picture frames
How many kg on a sheet
- Less than 8 kg: a screw-in anchor is enough
- 8 to 15 kg: an expanding anchor or a Molly bolt
- 15 to 30 kg: two Molly bolts or expanding anchors spaced apart
- More than 30 kg: screw directly into the metal studs behind the sheet
Tip: For heavy loads (TV cabinet, radiator), locate the metal studs with a stud finder and screw into them: a screw in the stud supports well over 50 kg.
The installation step by step
- Locate the area: avoid the studs if you are using an expanding anchor
- Drill with a drywall bit (no hammer action, or at a very low speed)
- Insert the anchor and open it up (screwing or pulling depending on the model)
- Screw the screw into the centre of the anchor
- Test the strength before putting the object under load
With the right anchors and careful locating, you can safely hang shelves, mirrors and even TV brackets on drywall partitions.
Looking for something else?
Browse all our DIY guides to find the solution for your project.