Have I ruined my slate floor?

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tom.ha...@gmail.com

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Aug 25, 2007, 7:30:18 AM8/25/07
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I hope I haven't ruined my slate floor! I've just laid about 25m2 of
slate floor. I followed all the instructions on all the packets, and
am now left with a floor with quite a lot of grout smeared around,
particularly in the riven bits. Trying to clean the (flexible) grout
off is turning out to be more work than laying the slabs!

I was probably a bit of a prat trying to grout the floor a couple of
days after knee surgery. Due to my lack of mobility, I don't think I
cleaned the grout off soon enough, or particularly well. I did however
seal the slate before grouting.

Any tips on how to clean th grout off would be much appreciated!

T

The Natural Philosopher

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Aug 25, 2007, 8:48:05 AM8/25/07
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Been there, done that.

Brick (patio) acid and a sponge. Use old jeans, rubber gloves and knee
pads. The acid should not attack the sealer, and doesn't attack the
slate at all. It will of course start to dissolve grout in the grooves,
but that can always be carefully put back if needs be.

In the end you will have loads of calcium chloride and sand everywere,
but that is washable off.

Its murder doing the grouting: If you had posted earlier I would have
told you how I evolved a system...that works.

Just be ultra happy it was slate, not limestone. That etches faster with
the acid than the grout does...

> T
>

Jeff

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Aug 25, 2007, 2:29:22 PM8/25/07
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On Sat, 25 Aug 2007 13:48:05 +0100, The Natural Philosopher <a@b.c>
wrote:
<removal of grout from slate tiles>

>
>Its murder doing the grouting: If you had posted earlier I would have
>told you how I evolved a system...that works.
>
>Just be ultra happy it was slate, not limestone. That etches faster with
>the acid than the grout does...
>
>> T
>>
Any chance you can enlighten us?

We are just about ready to lay a limestone tile floor in the kitchen
and we've never done this before. Any advice will be most welcome TNP.

Clive George

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Aug 25, 2007, 3:48:35 PM8/25/07
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"Jeff" <je...@bliayach-farm.co.uk> wrote in message
news:t3t0d3pkk3tv4o0a1...@4ax.com...

>>Just be ultra happy it was slate, not limestone. That etches faster with
>>the acid than the grout does...
>

> Any chance you can enlighten us?
>
> We are just about ready to lay a limestone tile floor in the kitchen
> and we've never done this before. Any advice will be most welcome TNP.

Anybody who's ever known the delights of caving, or even that of a karstic
landscape, will have experienced what happens to limestone when acid as weak
as C02 dissolved in water is allowed to attack it over a long enough period
:-)

Put acid on calcium carbonate, ie limestone, and it'll happily bubble away
and dissolve. Not manic miner disappearing floor fast, so you'll be able to
wash it off, but if you're trying to shift other stuff with acid, you'll
probably lose.

cheers,
clive

The Natural Philosopher

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Aug 25, 2007, 4:12:18 PM8/25/07
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TNP's advice to someone about to lay limestone in a kitchen?

DON'T.


On account of just about any acid will attacke it, its porous and it
stains..

HOWEVER if you must...

PEPARATION

1/. Take your time. PLENTY of time, and don't move on till one bit is
finished properly.

2/. I'd probably, with limestone, seal the tops before even starting to
lay, with at least two coats of the expensive Lithofin muckite.

3/. If laying over concrete slabs, use Ardex rapid set tile cement. Its
rubbery in an hour, andd rock hard overnight.

4/ Mix it WELL AWAY from your limestone. Mixing is a mucky job. I use
about a bucket full for a couple of large tiles.

5/. Measure the room carefully and run a string down the longest length
to check for flatness, slope and finished floor height. Take your time.
Yu beed at least 5-6mm of cement to give a good bed for the slabs. I
admit to using up to 30mm on my floor: My excuse was that it wasn;'t a
very good screed job. Use BIG level.

6/. Dry lay any critical bits - sometime you have to adjust your line to
get the tiles parallel to the most obvious features..and try noy to end
up with 10mm wide tile fragments at the edges...

7/. If the floor is very dry and dusty, slop a 50-50 PVA mixture on it a
day or two before laying.

Right thats the prep work. Time to lay the first line.

You need a bucket of cement, a bucket of fresh water, constantly
refreshed by a willing partner, a few packets of tile spacers and about
30 disposables sponges. You also need a spirit level - a smaller one-
and a pointing trowel and a flat blade scraper and a comb type cement
applicator thingie. A rubber mallet is good too.

Putting the tiles down is two parts. Getting them down, and cleaing up
the mess you will inevitably make.

PUTTING DOWN.

I generally on big slabs go one at a time. On smaller tile you can
indeed lay a part row. You should have a string to work to at least till
you get better. Unless your room is dead square do NOT start at one end.
Start somewhere in the middle, and gob a big pat of muckite down where
the tile will go. Try and get it level and correct, them comb it up with
the comb thingie, and splat the tile down.

One of four things will happen.

(a) you got the cement dead right, and a tiny tap gets the tile seated
perfectly with no extra squidging out of the sides, and no slop or rock
and the top[ surface is dead clean. In your dreams. That's what you pay
a pro £200 a day to be able to do. YOU are an amateur, and so am I...

(b) Its proud, and you tap away at it to get it down, and muckite
squidges all out the edges and up between it and the last tile. Don't
panic. On untiled floor areas remove surplus with a square ended
scrapery putty thingie, and use the pointing trowel to run down between
tiles to clear the surplus and leave room for teh grout. You will be
aghast, your wife will be screaming at you as her expensive tiles are
now smeared with cement, and she has visions of this being just another
DIY disaster. Reassure her that this is perfectly normal, and get her t
make a cup of tea or coffee.

(c) its too low, and there is no recourse but to lever the thing up,
getting it filthy, wash the top a bit add more muckite and go for a type
(b) scenario.

(d) its uneven. Ther are bits too hogh, and bits too low..sometimes you
can recover from this by elevering it up a bit and using the flat ended
scrapery thing to force more muckite under one edge. or a ruler to push
stuff sideways under to fill a hollow in the middle.

By the way do NOT use the '5 cowpat' method Maybe pros can get that
right and end up squashing the pats till they JUST touch. Every time
I've used it I've ended up with a 'rocking tile' he on;ly vis you shuld
have are what the scrapery comb thing leaves, ad not a lot of those either.

CLEANING UP.

Right. You have a couple of tiles - maybe three down, your bucket of
cement is empty, and what's in it is starting to go off. And te tiles
are COVRED in nerly as much filthy muckite as your jeans and arms and
legs. I don't to worry you, but you have about 10 minutes to clean up
those tiles or the goo will never come off.

First of all, park all the tools in the bucket and put it out of harms
ways. If assistant present order make tea/coffee, and more cement. You
have work to do.

First wash your hands and scrape the worst off your knees hopefully you
have 'borrowed' some really naff trainers from a teeneage offspring, so
you won't wreck any imporant shoes. Let's face it., Nike and Reebok are
only FIT to lay floors in.

Fill the water bucket with fresh clean water. Put in three or for
sponges and soak

Go via the unlaid floor to where you need to clean. Take a sponge and
squeeze it out and starting at one edge wipe it across the tile ONCE.

Then rinse it thoroughly and repeat. If the cement has gone a little
hard, use the scourer side (white scourers: NOT green) to rub away at
the cement. Use the sponge to remove cement between tiles - or a bit of
stick or trowel so that none will be visible after grouting.

Repeat this endlessly. Use fresh water often. You HAVE to get it all up
with limestone. Cement and limestone are virtually identical chemically:
Anything that takes cement (or grout) off.......:-(

DO NOT be despondent if it takes you twice as long to clean as it did to
lay. Just think how good a shag you will get when its all down. As you
get practiced, you will make less mess..

OK, thats it.

Seal that lot again before grouting.

Grouting is the same nightmare again, only worse, because half the time
you will wipe the grout out of the tile gaps. or get it watery and it
will crack and slump.

You will know every square centimeter of your floor better than you know
your wife, when you have done.

It took me the whole of the memorable last televised test series to lay
my kitchen with slate. I'd do about two square meters, and take a break.
I had 50m^2 to do...

But SWMBO thinks its great and people ask who I got in to do it...so it
can't be that bad...;-)


Jeff

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Aug 26, 2007, 8:21:16 AM8/26/07
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On Sat, 25 Aug 2007 21:12:18 +0100, The Natural Philosopher <a@b.c>
wrote:

>Jeff wrote:
>> On Sat, 25 Aug 2007 13:48:05 +0100, The Natural Philosopher <a@b.c>
>> wrote:
>> <removal of grout from slate tiles>
>>> Its murder doing the grouting: If you had posted earlier I would have
>>> told you how I evolved a system...that works.
>>>
>>> Just be ultra happy it was slate, not limestone. That etches faster with
>>> the acid than the grout does...
>>>
>>>> T
>>>>
>> Any chance you can enlighten us?
>>
>> We are just about ready to lay a limestone tile floor in the kitchen
>> and we've never done this before. Any advice will be most welcome TNP.
>>
>TNP's advice to someone about to lay limestone in a kitchen?
>
>DON'T.
>

Feck, am I glad I asked you :-)

I'd been cruising the tiling sites and they make it look a doddle. At
least I have some idea of the misery to come. Thank you very, very
much TNP, advice, converted to PDF for later use and to compare
experiences :-)

Andy Hall

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Aug 26, 2007, 8:55:45 AM8/26/07
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I'd completely echo what he says.

On the issue of suitability of materials, a few years ago I looked at
different stones for floors in hallway, kitchen cloakroom and
conservatory - e.g. whether to go for different ones or the same
throughout. The conclusion from everyone asked was not to go for
marble, limestone etc. for areas such a kitchens and near to outside
doors where there is a dirt issue. They might have been suitable for
the cloakroom but it wasn't worth it for one small area. Slate is
far more maintainable because virtually any cleaner can be used.
Limestone may be suitable for bathroom floors but that's about it
unless one has an area well isolated from sources of dirt.

These soft materials are suitable for wall tiling in most areas, so for
example, I've used marble in the kitchen and limestone in the
cloakroom. Again one has to be careful with cleaners but with
suitable impregnation with Lithofin MN Stainstop no issue.

The other thought with floor tiling is that it can be very hard work in
stone. I went for 600x400 slates and these are veryheavy to start
with. When held at arms length for tiling they become very heavy
indeed. I had a professional tiler do the job because frankly it
would have been back breaking for me and would have taken far too long.
As it was, this amounted to well over a week's work for two tilers.


The Natural Philosopher

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Aug 26, 2007, 4:23:13 PM8/26/07
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Its not misery, its just very very time consuming if you are a
perfectionist, unless you are a total pro.

The Natural Philosopher

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Aug 26, 2007, 4:29:47 PM8/26/07
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Slate is a very good material, so is sandstone though beware of 'too
much riven' stuff (dirt in cracks needs a scrubbing brush). Quarry or
terracotta tiles are good but have to be well sealed.


Steer clear of marble and limestone - they are too prone to acid attack
and staining.

Get quality tiles that LOOK like limestone etc...but can be acid washed
to remove grout splashes.

I'd only consider one of those materials in a bathroom floor, where
bare clean(isH) feet and no wine, vinegar or citric fruits are likely to
end up. Or maybe if you adopt Scandinavian or Muslim style living, with
shes off at the front door. and are exceptionally houseproud, careful
and have no kids and definitely NO PETS.
.

Mike Barnes

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Aug 27, 2007, 8:40:58 AM8/27/07
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In uk.d-i-y, The Natural Philosopher wrote:
>Get quality tiles that LOOK like limestone etc...but can be acid washed
>to remove grout splashes.
>
>I'd only consider one of those materials in a bathroom floor, where
>bare clean(isH) feet and no wine, vinegar or citric fruits are likely
>to end up. Or maybe if you adopt Scandinavian or Muslim style living,
>with shes off at the front door. and are exceptionally houseproud,
>careful and have no kids and definitely NO PETS.
>.

We had limestone put down professionally on our kitchen floor about
eight years ago. They did a fantastic job: 600x400 tiles, with 5mm gaps,
perfectly even and level. We take no special care of it other than a
good scrub and one coat of sealer a few years ago. Looks great.

So a couple of years ago when we wanted the bathroom re-done we went for
limestone again. Same grey tiles on the floor. The walls (well, one full
wall and three bottom halves of walls and the sides of the bath) were
done in creamy 400x400 tiles, plus matching windowsills and ogee
architraves and dado rails. Quite a complicated job done by a different
contractor and again it looks fantastic. The only problem stain-wise is
white soap stains in the shower, but to be honest we don't care. I've
seen lots of ceramic tiles that are supposed to look like limestone, but
they have nothing like the class of the real thing.

Going back to the subject, our hall floor is done in riven slate and is
also good-looking with low maintenance. It's important to leave wide
gaps between uneven tiles: the tilers had already laid half the floor
with 5mm gaps before I saw what they were doing, but after I had a quick
word with the boss they took them all up again and re-did them with 10mm
gaps. Much better.

Maintenance-wise the slate is very good except for a white stain caused
by a dripping TRV. One of these days I'll get round to finding out how
to get rid of the stains, but not before I've replaced the TRV :-).

--
Mike Barnes

Andy Hall

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Aug 27, 2007, 8:54:22 AM8/27/07
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On 2007-08-27 13:40:58 +0100, Mike Barnes <mikeb...@bluebottle.com> said:
> I've
> seen lots of ceramic tiles that are supposed to look like limestone, but
> they have nothing like the class of the real thing.

For me the point of irritation is being able to see the screen printing
on the fake tiles.

>
> Maintenance-wise the slate is very good except for a white stain caused
> by a dripping TRV. One of these days I'll get round to finding out how
> to get rid of the stains, but not before I've replaced the TRV :-).

Try this in order....

A wipe with a solution of Lithofin Wexa - about 20:1. It's a good
cleaner and you don't need to mix up very much - maybe a litre of
solution for quite a large area.

If that doesn't work then go for a scrub with some brick acid. Not
near the limestone of course.
That should move it. Then rinse thoroughly and go for the Wexa.
Rinse again and lightly polish.


Mike Barnes

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Aug 27, 2007, 12:36:30 PM8/27/07
to
In uk.d-i-y, Andy Hall wrote:
>>Maintenance-wise the slate is very good except for a white stain
>>caused by a dripping TRV. One of these days I'll get round to finding
>>out how to get rid of the stains, but not before I've replaced the
>>TRV :-).
>
>Try this in order....
>
>A wipe with a solution of Lithofin Wexa - about 20:1. It's a good
>cleaner and you don't need to mix up very much - maybe a litre of
>solution for quite a large area.
>
>If that doesn't work then go for a scrub with some brick acid. Not
>near the limestone of course.
>That should move it. Then rinse thoroughly and go for the Wexa.
>Rinse again and lightly polish.

Thanks I'll file that advice away for when the time comes. I've used
Lithofin products and generally they're very good.

--
Mike Barnes

Andy Hall

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Aug 27, 2007, 2:01:03 PM8/27/07
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I had the same situation and I think the deposit was just limescale
from the water. hence the brick acid dealt with it.

tom.ha...@gmail.com

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Aug 28, 2007, 5:33:54 AM8/28/07
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On 25 Aug, 13:48, The Natural Philosopher <a...@b.c> wrote:

The tiling shop where I bought the adhesive/grout/tools etc. told me
that under no circumstances was I to use brick cleaning acid on my
slate floor as it would totally ruin it. I popped round to Wickes,
which don't sell it. That's 2 fairly common items you might need when
building a wall they don't sell - lime and cleaning acid!

B+Q thankfully sell Feb acid based cleaner (I think it's got detergent
in it too), which my wife has been applying neat to the floor. (I
still would have to scuttle around on my backside after my knee op.).

The floor is cleaning up very well - thanks for the tip!

T.

The Natural Philosopher

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Aug 28, 2007, 7:32:19 AM8/28/07
to

Oh dear. I must have totally ruined mine then ;-)

Utter bollocks. Slate is acid proof.

I popped round to Wickes,
> which don't sell it. That's 2 fairly common items you might need when
> building a wall they don't sell - lime and cleaning acid!
>
> B+Q thankfully sell Feb acid based cleaner (I think it's got detergent
> in it too), which my wife has been applying neat to the floor. (I
> still would have to scuttle around on my backside after my knee op.).
>
> The floor is cleaning up very well - thanks for the tip!
>

Thats brick acid anyway, is feb..check the details.. bet you its
actually HCl. Or it MIGHT be sulphamic or formic acid...

> T.
>

Aidan Karley

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Aug 28, 2007, 5:44:52 PM8/28/07
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In article <46d3...@nt1.hall.gl>, Andy Hall wrote:
> I had the same situation and I think the deposit was just limescale
> from the water. hence the brick acid dealt with it.
>
Depends where you are : limescale is generally
(calcium,magnesium) carbonate, so your "brick acid" (sulphuric, IIRC)
should get it into solution so you can take it away. But in some areas
there is a significant amount of calcium sulphate in the limescale, and
*that's* not going to shift with any over-the-counter acids. On the
other hand, it's soft (2 on Moh's scale, couple of dozen on the
engineer's hardness scale whose name I've forgotten), so a mild
abrasive might be adequate. Table salt should do the job, and wash off
with water afterwards.
When I grew up in a hard water area, we didn't have central
heating. Now my teeth hurt whenever I go to hard water areas, unless I
drink beer only. Now there's an excuse!

--
Aidan
Aberdeen, Scotland
Written at Tue, 28 Aug 2007 16:04 +0100, but posted later.

FKruger

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Aug 29, 2007, 12:22:04 PM8/29/07
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