Heavy radiator on to Plasterboard

[cwcw]

I have a 40kg double bank radiator to fit on to a wall that I've now realised is all plasterboard and with no stud for the position it needs to go, underneath a straight section of bay window.
I had bought some of these:

https://www.toolstation.com/fischer-radiator-fixing-set/p88335

On the packet though they state a max weight of 20kg. There will be 8 fittings in total, to fit each of the 4 brackets.

Does the 20kg mean per fitting or the whole weight regardless of number of fittings?

I've since found some Grippit fittings that go up to 113kg but require quite a large hole drilling.

https://www.screwfix.com/p/gripit-plasterboard-fixing-25-x-14mm-8-pack/682gk


I think my options are, easiest to hardest:

1) Go with the fittings I've already got
2) Get the Grippit fittings
3) Attach plywood to the nearest studs spanning the radiator and down to the floor (refitting skirting over it). Being under a bay window it will be relatively seamless
4) Hack out 2 horizontal strips where the brackets will go and fit 2 thick wooden battens spanning the two studs, then replace the board, make good and fit the brackets
5) Remove the entire piece of plaster board, fit battens as required and including floor joist support, fit new sheet of plasterboard or reuse old if possible, make good and fit the brackets

Are there any other options? Which is the best for the weight of radiator involved balanced with the amount of hassle?

Any advice appreciated. Thanks.

 

[denso13]

4 or 5, do it properly now and you won't need to worry about it in the future.

 

[JP_]

Or long screws into the brick. For a wall that I insulated (50mm kingspan+10mmplasterboard) I used screws and plugs about 12cm long. Can't remember what sort, something like this I guess

https://www.toolstation.com/rawlplug-kks-r-high-performance-nylon-frame-fixing/p41903

 

[MJN]

Does the 20kg mean per fitting or the whole weight regardless of number of fittings?

Per fitting, but be careful how much you read into this as it won't (can't) factor in the security of the board itself i.e. it might be held on with just a couple of screws, glued on, being held up by tape etc!

I've seen some quite remarkable loads being held up by plasterboard alone but personally I'd go for the battens if it's not too much grief then not only does it give a solid support for the radiator (and water) but anyone leaning on it too.

 

[Agile]

I am always suspicious of those fancy fittings. Seen too many failed.

My preferred method is to get a sheet of 22mm plywood or better MDF or similar and fix it firmly onto the studs.

Then fit the rad brackets to the sheet after drilling additional holes in the brackets.

 

[cwcw]

In the end, I went for option 5 but discovered some additional studs so only needed to remove 2 smallish sections, fitted in battens to match the bracket position, then refitted the plasterboard and filled the edges to make good. It's a very solid fit, even if it did add a few hours on to the job (and a lot of dust).

 

[Martyn R]

I had the same dilemna. 34 Kg radiator (without water) for a wall which has 50mm insulation then 15mm plasterboard onto an old (1930) plastered brick wall (somebody decide at some point for good reason I think to insulate the whole wall like this) . Radiator needed 6 brackets. 2 screws in each. One easy solution seemed to use Fischer 42793 (7Kg rating so total 12 x 7= 84 KG if can calculate in this way) into the plasterboard but was not keen on this in case radiator comes away with the whole plasteboard section and then floods downstairs including an expensive piano and house insurace not paying out.

Instead having read the above options went for something similar:

Establish where radiator support brackets need to be.
Cut out a section of plasterboard then the insulation down to the solid wall at each bracket position ( with a multitool)
Screwed to wall a vertical wood batten of approprate depth at these cutouts.
Fitted Rad brackets to these battens.
Filled and make good

Hence rad is fixed to the wall not the pasterboard,

 

[Jackrae]

I've used option 3 on several ocassions, on plaster-on-lath walls. I found 18mm MDF suitable. Yes things do end up 18mm further out and sometimes the sheeting extended beyond the radiator but mess in doing the job was minimal