# How can I estimate the maximum load on shelves on a plasterboard wall? [duplicate]

Possible Duplicate:
How much weight can you mount to a wall?

(Apologies for asking here whilst not a serious DIYer, but as a Stack Overflow user it seemed like the obvious place!)

I would like to add some shelves to a wall in my house, but as the wall is only plasterboard, I am aware that the shelves won't be able to take much weight. By knocking I can only detect a wooden baton behind one end, so I suspect the other end of the shelves would just have to screw into the plasterboard with nothing behind it.

Is there a good rule of thumb for estimating how much load the shelf would be able to take (e.g. kilograms per shelf bracket or somesuch), and if so, is there any extra information I need in order to calculate it (e.g. thickness of plasterboard)?

• @Tester101, question is similar, but this one seems to be asking how much weight can the plaster/drywall hold alone, without hitting a stud.
– BMitch
Commented Nov 5, 2011 at 12:06
• @BMitch what is the usual maximum load for drywall was closed as a duplicate of the question I linked to. And this question is a duplicate of that closed question. Commented Nov 5, 2011 at 13:27
• Hmm, now I'm tempted to click the reopen on that question :)
– BMitch
Commented Nov 5, 2011 at 18:34

Your wall probably is not just plasterboard. Its much more likely that your wall has 2x4 studs (vertical boards) behind the plasterboard spaced 16" apart.

Knocking, by the way, is a remarkably unreliable method for finding studs. :)

The load bearing capacity of drywall/plaster/etc should be treated as practically nothing. What you should do is find your studs - buy a stud-finder OR drill holes in a straight line horizontally across your wall spaced 1" apart, until you find one that is harder to drill into than the others. Then measure 16" in both directions horizontally from that hole and drill again - and so forth to find your studs.

Once you know where the studs are, mount your shelving brackets into the studs using 3" wood screws (Pre-drilled holes please!).

Anchoring into the wood properly will ensure that your shelves will stand up to pretty much anything you'd normally see on shelves.

• +1 for drywall having no load bearing capacity. In other words, drywall can bear its own weight, a picture frame, and a towel rack. And with the towel rack, I still try to get one side in a stud.
– BMitch
Commented Nov 5, 2011 at 12:09