Help! How to hang cupboard on plaster board where heating pipes run up stud??

[opps]

Long story short Opps, I've just had these fittings fail.

I priced to contractor on new build penthouses, in my terms I put "all stud walls that receive shelving to be ply lined". They didn't, I moaned, they didn't care, I used the fixings mentioned. Customer loaded shelves with plants, the whole lot came crashing down, damaged worktop, damaged floor.

I get the blame, until I refer them back to my T&C's and subsequent conversations. I can't do my job professionally if they don't do their job professionally.

I don't trust them for wall units either.

Did they burst through the plasterboard?

 

[chirpychippy]

Did they burst through the plasterboard?

They did.

 

[opps]

They did.

Out of interest, were they the 4mm or larger.

I have used both the 4mm and 5mm Fischer ones. I am less impressed by the 4mm ones. I have had a few where tightening the screw (after using the setting tool) striped the internal threads.

 

[roxburd]

Job done!

I used Diall M5 x 80mm spring toggles.

I hung the lower one with three toggles along the back and one through the side wall. And when I took the supports away... it didn't fall down! Hooray. So far so good - it could support its own weight of 15Kg.

So then I took the second one and laid it on top of the first one, as that was where I was installing it. And it still didn't fall down! Hooray again!

I was glad to have steel toe-caps and even more glad that they didn't get tested

So now, with both secured to the wall and secured to each other, I know that between them they can take 30Kg in addition to their own weight, at least. That's quite a lot of pots and pans.

How much weight the plasterboard will take before it comes away from the studs, I have no idea. But given that the units are fixed to the back wall and the side wall, the board/stud fixings would have to fail in shear since the forces won't be moving the boards and studs away from each other. At a complete guess, I reckon it's good for 80Kg or so.

Cheers guys, advice and input much appreciated.

 

[chirpychippy]

Out of interest, were they the 4mm or larger.

I have used both the 4mm and 5mm Fischer ones. I am less impressed by the 4mm ones. I have had a few where tightening the screw (after using the setting tool) striped the internal threads.

I'm not sure now.

I think the force applied when using them for shelving is different to the force when using for wall units.

Wall units are a vertical downwards force, whereas shelving is outward force, I think the bracket pushed through the plasterboard weakening it and causing the cavity fixing to rip through the plasterboard.