What's behind my plasterboard?

Hebrews12

Hi all. I'm trying to nahg up my son's guitar on his wall and found what I assumed was the wooden stud behind the plasterboard. I drilled through and there was no wood but I've now hit something hard that I can't get through. I've downloaded a metal detector app on my phone and it's confirmed that there's metal there. It's on an extension that was built about 8 years ago and the other side of the wall I'm drilling into is an external wall. There's no rads on that wall. Any ideas what it could be and how I should proceed please? Thank you.

WIAWSNB

https://forums.moneysavingexpert.com/discussion/6672594/whats-behind-my-plasterboard

Use the detector to figure out which way the metal(s) run, and how far apart they are spaced. Ie, see if you can work out if it's metal 'stud'. Studwork should be floor-to-ceiling, and evenly spaced, typically 400 or 600mm apart.

Of course, it could be protective metal trunking/capping for cables, in which case good job you didn't drill through 😀 Is this position in-line with any sockets or switches?

In-law's Persimmon home used some form of lightweight metal frame to mount the internal - possibly external too - p'board, which I discovered when I put wall units up for them. I ended up drilling pilot holes, and 'taping' the screws in to the quite thin metal - it held well.

When you say you cannot drill through, what quality bits are you using? (Tho' obvs don't drill until you know what the metal is for…)

And, what type of hanger? And how costly the geetarrrr…?

Hebrews12

https://forums.moneysavingexpert.com/discussion/comment/82035513#Comment_82035513

Thank you for your reply. I've just had another look and there is a socket at the bottom of the wall but it's about 6 inches over. I've run the metal detector again and it's saying there's metal from where I've drilled to about 10 inches below but then nothing after that and nothing above it or to either side which seems strange right?

FreeBear

Could be an RSJ or heavy gauge conduit. Steel capping covering electric cables tends to be pretty thin, and even a masonry bit would go through the stuff without much trouble. Metal framing used with plasterboard, again is relatively thin, but a blunt masonry bit may well complain.

Personally, I'd drill a new hole 150mm or so to one side and slap a bit of filler in the old one. Unless you have first hand knowledge of what is behind the plasterboard, best to play safe.

WIAWSNB

https://forums.moneysavingexpert.com/discussion/comment/82035521#Comment_82035521

Yes, very strange!

Many metal detectors can be quite vague, so something as small as a p'board clout nail or screw can suggest a larger object.

If they are fixings like above, then you should get further readings as you slowly make your way straight down.

FreeBear's thoughts are worth checking. Could we have some pics showing that wall, please, and also a sketched plan to show where that wall is in relation with the rest of the house?

You say it's 'external' - is it one of the new walls of the extension, or part of the original house? Anyhoo, some pics might help.

Does your detector also have an AC voltage function? Any readings from there?

Section62

https://forums.moneysavingexpert.com/discussion/comment/82035521#Comment_82035521

Don't rely on a phone app metal detector. In fact don't rely on any metal/voltage detector when drilling holes.

As FreeBear says, (carefully) try somewhere else in the wall.

TroubledTarts

It sounds like you have enough room behind for these type of plasterboard fixings

More than enough for a guitar and plenty of others things like this just for plasterboard

https://amzn.eu/d/0d3Ytdej

twopenny

Wow those look amazing TT. Have you used them?

I had a nightmare getting multiple plasterboard fixings out of the walls when I moved in here. In fact the metal ones are still there despite the forums advice.

MyRealNameToo

https://forums.moneysavingexpert.com/discussion/comment/82036569#Comment_82036569

I've used them, but for something much heavier than a guitar. Have several guitars and equivalent on out wall using Hercules holders and more modest hollow wall anchors but with two screws in each means they should hold 40kg which is 8x the weight of our heaviest guitar.

For truly heavy things you can also get specialist mounts for dot and dab walls which drill into the brickwork behind the plasterboard and have a metal sheath that bridges the gap between plasterboard and wall rather than rely on the strength of a 4-6mm screw

twopenny

Definitely bookmarked then 🙂 thanks.

WIAWSNB

One of the tips for any of these types of fixings is to make sure the drill bit is sharp, and you drill pressing gently through - you almost have to hold the drill back. Try and ensure it cuts cleanly through the rear paper backing, and not burst or tear through. The paper coverings are what gives the p'board a lot of its strength and prevents it from crumbling.