Some large tile questions .....

[picbits]

Hi

I've done a fair amount of DIY tiling in the past without any problems but the wife has now decided she wants the ensuite decked out in 600mm x 300mm ceramic tiles (10mm thickness).

I've done most of the structural work for an enclosed shower - 1200mm x 900 tray in a recess that has been built from 4x2 studwork with 12mm Aquapanel. Area isn't huge - around 7m2. Walls are less than 1.5mm out of flatness measured from any two points.

I've also been informed by the better half that I have to fix the tiles in a vertical staggered pattern (which also seems to highlight any issues with tiles / wall flatness etc).

From reading up, I should use an adhesive from Wickes in a tub ......

Actually - I was planning on using BAL single part flexible with a 10mm round notched trowel, 3mm tile spacers (I think 2mm might be a bit tight with the tolerances of the cheaper tiles she's after) and a lot of luck.

There is also around 3m2 of tiling to do around the sink / toilet (before fitting) onto skimmed plasterboard which has been dot and dabbed to the - the tiles work out at just under 19kg / m2 so including adhesive is more than the 20kg/m2 recommended for skimmed walls. I've explained this to the other half but been told "it will be ok - the toilet and sink will hold the tiles on" so that will be her problem if they all fall off lol.

Have I got the above reasonably correct ?

Cheers

 

[Richard C]

I've done a fair amount of DIY tiling in the past without any problems but the wife has now decided she wants the ensuite decked out in 600mm x 300mm ceramic tiles (10mm thickness). I've done most of the structural work for an enclosed shower - 1200mm x 900 tray in a recess that has been built from 4x2 studwork with 12mm Aquapanel. Area isn't huge - around 7m2. Walls are less than 1.5mm out of flatness measured from any two points.

Do you know the actual weight sq/m? No problem for Aquapanel which will take 50 kg/sqm but it could be marginal on plasterboard (32 kg/sqm) & forget it on conventional plaster which will only take 20 kg/sqm (excluding addy/grout)

I've also been informed by the better half that I have to fix the tiles in a vertical staggered pattern (which also seems to highlight any issues with tiles / wall flatness etc).

Large format tiles need a flat surface & a problem with staggering is that any bowing on the tiles will cause noticeable lippage so I would carefully check the manufacturing tolerance on the tiles before going down that route.

From reading up, I should use an adhesive from Wickes in a tub ...... Actually - I was planning on using BAL single part flexible

For gods sake don’t do that; tub ready mix is of no use whatever on tiles that size & cheap own brand & DIY products are mostly crap.

You must use a powder cement addy; go with your original choice BAL SPF or Rapidset flexible; I prefer it but it only has a pot life of 40 minutes.

with a 10mm round notched trowel, 3mm tile spacers (I think 2mm might be a bit tight with the tolerances of the cheaper tiles she's after) and a lot of luck.

Use a thick solid bed trowel - 20mm round notches, 10mm deep, at 28mm centres; this will help you even out any small discrepancy with wall flatness but obviously won't help with tile bowing tollerance if you stagger.

I would use BAL Microflex grout but don't use grout in the corners where adjacent walls meet; run a bead of silicone down there as with the (2mm gap) between the tray & the tiles.

There is also around 3m2 of tiling to do around the sink / toilet (before fitting) onto skimmed plasterboard which has been dot and dabbed to the - the tiles work out at just under 19kg / m2 so including adhesive is more than the 20kg/m2 recommended for skimmed walls. I've explained this to the other half but been told "it will be ok - the toilet and sink will hold the tiles on" so that will be her problem if they all fall off lol.

As long as she doesn’t blame you if they fall off the wall; why do women always want to interfere in things they generally will know nothing about

Are you sure about that tile weight? Adhesive manufacturers do not recommended fixing tiles over 8mm thick to plaster &, depending on what they are, 10mm thick tiles usually weigh in around 25-30 kg/sqm + 4 kg/sqm for adhesive/grout which is far too much for plaster; it’s always best not to skim PB that’s being tiled. Moisture Resistant PB should also be used in a bath/shower room not ordinary wallboard.

I would imagine there is a safety margin in the published maximum weights & my guess is it would be around 10% but I’ve no real idea. If your tiles & addy come in at much more than 22 kg/sqm (& I’m pretty sure 10mm thick tiles will), I think you’re pushing it. When tiling onto D&D, you should also stick some mechanical fixings through into the wall or the whole lot could end up on the floor. Plaster must be acrylic primed when using cement powder addy to prevent a reaction with the gypsum in the plaster.

Your not tiling onto a suspended timber floor by any chance are you?

 

[picbits]

I was joking about the Wickes adhesive by the way

I've talked her out of tiling the floor - going to slap down some decent vinyl.

I calculated a tile at almost exactly 0.2m2 (they are slightly over 600 x 300) and weighed one on the scales - worked out at just under 19kg/sqm tiles seem reasonably true but if she insists on staggered then I'll make sure I check every single tile before they go up.