On 18 July, 00:03, Tim Watts wrote:
David Robinson
* wibbled on Saturday 17 July 2010 22:31

On 16 July, 19:28, Tim Watts wrote:

I grouted the corners using Mapei Keracolor grout powder and Fugolastic
additive - slightly flexible grout with mental adhesion.

BTW - I hand mixed (SS metal bowl + wooden spoon worked well), this grout
spoon mixes very nicely without trouble. But it is *very* sensitive to
ratios. I found an old food container that help 1kg power, then used another
container on the kitchen scales to measure 300g liquid (it's 100:30 ration
in the sheet). It starts off not much stiffer than double cream, but after
the 2 mins rest and restir has thickened up a lot. It then stiffens further
as you work over a 20 minute period which is the most you want to do before
a sponge off and grout finish.

Don't try to mix by eye until you've mixed by measurement - it takes time to
get used to it (probably true of most of the products). You can dash a
couple of tablespoons of extra powder or teaspoons of liquid in to tweak it
if required.

1kg powder gives a nice amount that reasonably swift but not looney working
will use up. New grout (well this stuff) blends to dried grout
beautifully[1] so it's best to deal with what's on the wall after 20 mins
max, get it perfect. Don;t try to clean the tiles of milky haze yet, just
get the lumps off and the grout recessed as you wish. Do another gentle wash
down about 40-60 mins later, ie quick wipe with uber clean water just before
you finish the 2nd batch that you just splatted in.

[1] I used white - might be more problems with the coloured stuff so beware.

An hour or two (max) after you finish the wall, dry buff the lot.

Thank you Tim, and thank you all.

A plan is forming. Annoyingly I can't avoid a silly small cut tile at
either the corner, or the window Never mind.

as long as you've looked, there'll often a few - you just want to minimise
it where possible for your sanity - and final look.

TBH white tiles and white grout obscure most visual weirdnesses. Strong
contrasts in colour will accentuate.

Are you going to use white grout and coloured tiles, or a similar coloured
grout? BTW - Mapei do a range of silicones (Mapeisil IIRC) that match a
subset of the Keracolor grouts which is handy and their silicone handles
very nicely.



Just found out that I've unwittingly bought porcelain tiles for the en
suite walls.

That's score'n'snap out then?

Floor tiles (and wall+floor tiles for bathroom) are
ceramic (despite "matching"!). En suite wall tiles are also big +
heavy (500x330mm).

Right - you want a really good high grab adhesive. I would consider
Green/Bluestar but read the data sheet grab. There are more optimised
products for large tiles. Greenstar will hold them fine once dry but it
would be nice if they behaved whilst you're sticking them on.

Check BAL and Mapei's website - if there is something that's better, I
suggest considering it - and wait for any other advice here.

Get SWMBO and take 2 tiles and try them dry next to each other over the
wall. That will tell you if you can expect any problems lining them up and
whether you can get away with the minimum adhesive thickness or whether you
need more bed to allow adjustment. You'll obviously have to make this
decision in order to decide what slot depth on the trowel to buy. I used a
4mm trowell but my tiles were small and the walls good enough and I wasn't
seeking perfect flatness.

I used a much corser trowel on the floor so I could tweak the tiles and get
them dead flat, especially where it really mattered like under the loo.

I can't remember if you said the walls were newly plastered - if so, BAL
recommend priming any polished new plaster with dilute SBR which I did. I
also scratched the polish with a wire brush first. This would be perhaps
more prudent in the wetroom and showers.

Two more quick questions...

How do people decide what size tile spacers to use?

It's a matter of taste, though erring on smaller is usually better IME than
erring too big. If the tiles have bevelled edges the grout line looks bigger
than the gap - which I didn't appreciate until I'd laid some. 2-3mm of the
wall is a generally safe bet but your design might call for larger, though
this makes grout finishing a little more difficult.

The pro who did my slate floor used surprisingly small gaps - about 2-3mm
which I didn't expect - but they look good so I guess he knew what he was
doing.

Do people make the wall and floor tiles correspond in any way? i.e.
try to make joins match? I can't see that they will (or even can, in
the case where the tiles are different sizes!). Diamonds or squares on
a floor?

I didn't. It will make life harder if you try because you'll have to do it
everywhere which might be difficult one end of the room to another. Safer
IMHO to deliberately make it look like there is no intended alignment.

If all this is purely aesthetic, I'll ask the boss!

This is usuall (IME) where the boss excels. As long as you make any
technical constraints clear and do not give in if it will break the job or
make it 100 times harder, let her come up with the general artistic stuff..

I found it useful to draw marks on the wall to show where tile tops (for
half tiled walls) and patterns would go. Then she can tweak them.

My SWMBO chose the colours and tiles (working to a nice-and-quality-but-at-
a-sensible-price constraint) and came up with the patterns once I'd
specified that she shalt use =15cm tiles (I knew bigger tiles would be
troublesome here for technical reasons - though using 10cm tiles did mean
I've laid nearly 1000 of the buggers in a small room!), must be ceramic for
walls and definitely no bloody travertine (that took some arguing but I
refused to shift - I hate the stuff, too much like swiss cheese and too
pourous) ;-

Once I'd worked out the general constraints, she came and helped pencil up
the walls for where the tops finished, where the patterns went and stuff
like that.

The result was that with a general lack of modesty, I do feel I've done the
walls like a pro (albeit at 1/10th of the speed!) and she agrees. I'm not a
pro so I choose easier materials to work with where possible.

I could have done the floor better, but it was my first floor. The tiles are
perfect but I over rubbed the grout and had perhaps a little too large a gap
too. I *also failed to have sealant at hand so they got grubby fast.

Yesterday I went over with another layer of grout and brought it just under
flush and sealed it it twice, immediately. You're not really supposed to
grout over grout, but I'll probably get away with it as it's a low traffic
area and the Keracolor + fugolastic is very adhesive stuff. It looks cool
now and if it goes tits up down the line, it's not too much to cut out the 3
or so linear metres with the Fein and redo.

HTH

Tim

I'm printing all this out so I can refer to it as I go along!

Another question: in the corners (and floor / wall joint, and tile/
bath joint) I'm intending to use silicone. Do I leave a small gap
between the tiles to fit this in, or butt them up and put silicone on
top?

TIA!

Cheers,
David.