Tiling a diagonal wall?

24 Nov 2008
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United Kingdom
I'm going to tile the en suite of a new loft extension. One side of the shower area is under the roof rafters. It is currently finished in plasterboard and skim.

I know that max tile and adhesive weight for this background is 20kg / m2 if it is vertical.

Any idea what max weight would be at 45 degreess?

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I would guess that it is the same. The max weight is about how much the substrate can support. Whether this is vertically or sloped the force acting and the weight is the same.
yep i agree. the manufacturers are non specific, there has been a lot of speculation around the fact that the max weights are based on something being fixed to the underside (as if you tiled a ceiling) but i've never seen confirmation\denial of this.

This is the reason a lot of people question the max weights in the first place (stating that when vertical the weight is less)
Thanks for that.

Or is it more of a case of how good is the substrate that the tiles are fixed to? For instance, if one was to tile a sheet of plasterboard that was leaning against a wall, then I can see that not much would happen. However if same sheet was fixed to a ceiling without adequate quantitly of screws then I can see how the weight of the tiles could compromise things...
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no, the weight calcs published are really telling you what a plaster skim will stand before the weight causes it to seperate, same for pb - how much weight before the board itself splits.
What's the thickness off the trusses..and these will be centred at 600mm
This is what your plasterboard is fixed to.....!!

So IMO look into braces and strengthening these and fixing a backer board..

What type size off tiles you fixing...

Again mate it's the trusses/spacing between these and thickness I would be worried about..this is the weight loading area...
Thanks for that. I can see that tiling it could be a bit of a faff for something that may not look so great. I am now leaning towards putting up upvc panelling instead...

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