Total weight on a plasterboard wall

[rick1632]

I'm planning on putting floor to ceiling shelves up in my old airing cupboard.

80cm wide, 50cm deep - secured on 3 sides to batons screwed to the 15mm plasterboard which is supported on a metal frame.

My understanding is that regular plasterboard rawplugs can take 6kg load safely, so 10 of these per shelf divided among the 3 batons SHOULD give me a safe load per shelf of 60kg.

My next concern though was total weight on the wall itself as if I had 5 of these shelves, that's 300kg total and when I read about heavy loads, it always says fix to the studs/frame.... but then I figured that since the board is screwed to the frame I only need concern myself with the strength of the individual fixings I use as the overall load of each shelf will be transmitted to the frame right?

i.e. I need to concern that each shelf is supported adequately, but if it is, the weight of that shelf is supported by the frame, NOT the board itself regardless of how it is fastened.

Is my thinking right here?

 

[foxhole]

What are you storing? Dead bodies?

 

[rick1632]

Tools - I keep the bodies in my freezer mate, doesn't everyone?


It's been my tool cupboard for years, but it's a total mess in there - the existing shelving is only 4'6 high and not that deep.

Hmm - 60kg for every shelf is probably unlikely - just weighed my router box and it's 5kg and 13cm wide - so I'd expect to get 6 of them on one shelf at the back - 30kg + weight of shelf, plus maybe another 5kg for stuff along the front - say 45kg total.
On another shelf though, my plaster tools probably only weigh about 20kg total.
But there's other heavy things...

I've realised though that the limiting factor is likely to be the screws mounting the board on the metal frame - particularly as the verticals appear to be every 80cm..

 

[Deleted member 174758]

Personally the only fixings I trust in stud walls are ones like the Rawl or Fisher plasterboard fixings - the all metal type which require a setting tool. We often refer to these as "umbrella" fixings because of what they look like when used. But if you are going to load a stud wall the way you want to you'll need to get as many fixings as you can into the metal laths in order to transfer as much of the load as you can into a structural element, and then add "umbrellas" where there is only PB. The other thing you'll msybe need to consider is the shelving type - a wall rail mounted system such as Spur (or one of the many copycat systems on the market) is possibly a better way to go because the rails spread the load potentially over the full wall height. The trick is to use more uprights than you need (possibly every 200mm) and get a screw and fastening in every hole

 

[rick1632]

a wall rail mounted system such as Spur (or one of the many copycat systems on the market) is possibly a better way to go because the rails spread the load potentially over the full wall height. The trick is to use more uprights than you need (possibly every 200mm) and get a screw and fastening in every hole

If my only option was a flat wall, then I'd agree, but having the two side walls to use it would be crazy to attempt to put all the support on the rear one.

I'm currently leaning towards a floor standing, but wall supported system instead then I won't ever worry about how much weight I put on the shelves - just trying to get my head around the easiest way to build it - not helped by the rear wall having quite a curve in it - the centre is about 8mm deeper than the corners, or the presence of boxing on the RHS, 19cm out from the corner, 13cm wide and sticks out 4.5cm, and (difficult to tell currently with the curves and the boxing) I suspect that the RHS is a few degrees out of a right angle.

I've also got skirting to deal with if I wanted to set my "feet" into the corners.

Update- I decided to rip the front off the boxing - the sides are wood about 34mm deep which is perfect - I can simply extend the boxing to the depth of the shelf - two 34mm square posts in front and and back corners and cover with something like 9mm mdf - it means I've boxed out more than i need to for the pipe, but makes cutting the ply a whole lot easier! Batons can screw direct into the CLS posts so that's the RH sorted.

On the LHS I can do the same - although considering using 2x1 instead which is 18mm thick so I don't box out as much - I can run 3 lengths rather than two - one in the middle for extra strength.

The rear piece I'll fasten to the wall - I could add little right angle support brackets at each side but I don't think necessary, and finally a 2x1 across the front, secured to each side with angle brackets and glued to the edge of the shelf to hide the plywood.

I think I have a plan!

 

[Eccles]

I have seen too many disasters with folk trying to put relatively heavy items on stud walls without going into the timber. It's not difficult to find the timber with an electronic detector. On one occasion I stripped off a section of plaster board and replaced it with some 20mm ply so that I could hang a heavy item on it.

 

[rick1632]

I have seen too many disasters with folk trying to put relatively heavy items on stud walls without going into the timber. It's not difficult to find the timber with an electronic detector. On one occasion I stripped off a section of plaster board and replaced it with some 20mm ply so that I could hang a heavy item on it.

If you'd read the thread properly you'd see my concern was not about attaching the stuff to the walls, but the underyling strength of the walls themselves which I decided wasn't going to be anything like sufficient - so how I attached the shelving is immaterial. A structure is only as strong as the weakest link.

In the end I built a floorstanding structure using pocket screws to attach crosspieces to four 3x2 corner posts. The weakest link is now the rafters underneath which as they originally supported a HW tank in this location shoudl be good enough for my collection of tools