Tiling question

IM

As ever, the good old t'internet is giving me confusing and conflicting information - so I'm coming to you guys for clarity...
About to use these tiles to tile my bathroom floor - https://www.toppstiles.co.uk/victorian-mosaics/victorian-black-white-chequer-tile - and I am trying to establish the size of trowel to use.
(They are a c2" mosaic tile on a mat of 6 x 6)
The place I got them from (considerably cheaper than from Topps...) suggested a 10mm trowel, whereas there are folks online saying mosaic tiles should be done with a 3mm trowel.
On the one hand, I want to have a sufficient adhesive bed to keep the tiles fixed, and accommodate any slight deviation on the substrate - on the other, I don't want a quagmire that splurges through the gaps in the tiles, when I give them a push to bed them in.
I suspect common sense says I should go for something in the middle - say 6mm - but is there any reason not to?

neilmcl

I think the general rule is 1mm per inch of tile (plus 2 inches) but as these are mosaic tiles then you want something much smaller. Topps Tiles themselves recommend a 3-4.5mm trowel.

Are you going to use mosaic tile backing board sheets?

IM

neilmcl said:

I think the general rule is 1mm per inch of tile (plus 2 inches) but as these are mosaic tiles then you want something much smaller. Topps Tiles themselves recommend a 3-4.5mm trowel.

Are you going to use mosaic tile backing board sheets?

Hadn't spotted the Knowledge Base at the Topps website - thanks for that.

However, again, there's contradiction  - https://www.toppstiles.co.uk/knowledge-base/fixing/trowels/trowel

The same page states:

As a general rule for which size trowel to use, follow this generic banding:

• Mosaics/ small format tiles (10x10cm or smaller) – 3-4.5mm

And then lower down...

Floors

Starting at the furthest point away from your exit, use a bucket trowel to apply a suitable amount of adhesive onto your notched trowel and spread the adhesive across the floor. A larger notched trowel (8mm+) is needed for floors to ensure the tile has 100% coverage and no hollow spots are formed.

neilmcl

I would suspect that latter part is more for the larger floor tiles rather than mosaic sheets.

FreeBear

neilmcl said: I would suspect that latter part is more for the larger floor tiles rather than mosaic sheets.

And if you are doing large format floor tiles, it is well worth back buttering them - Basically, putting a thinish coat of adhesive on the back of the tile before laying it. Almost guaranteed 100% coverage without any voids. Use one of the tile leveling systems, and you will get a perfectly level floor without any lippage.

But with mosaic tiles, all of the above is irrelevant. If you do get any adhesive oozing through the gaps between the tiles, wipe it down with a damp sponge before the stuff has set. You may need to wipe the surface down several times. Using an adhesive that is the same colour as the grout is also a good idea.