Calibrated tiles

[Gazzer]

Another thing to consider is joint width, I would recommend 20mm minimum. Any bad lips can be dressed with a chisel, prior to sealing.

I have some pics somwhere, I will try to dig them out

My client wanted 3mm joints....or less :yikes:

 

[jay]

My client wanted 3mm joints....or less :yikes:

Has he been told today

 

[Perry]

In over 30 years of fixing this natural material I've only ever sent back slate once and that was due to the poor quality and uneven layers in the riven surface.
It's a fantastic product with a unique rustic appearance so if you want perfection rather than aesthetics perhaps go for an alternative lookalike.
In my humble opinion the calibration of the tile is the surface area measurements and due to the nature of the riven surface some variation in the thickness is to be expected.

john in thirty years i have never sent any slate back :lol:

 

[One Day]

Calibrated refers to uniform thickness. Rectified refers to machine-cut edges with uniform dimensions to tight tolerances.
Riven means riven. You can't have calibrated riven. That's like having a cold cup of hot tea!

You can normally see the marks on the back of the stone where it has been through the machine to calibrate the thickness.
As it's a riven face you can expect variation but it shouldn't be massive. 1-2mm most.

I recently refused to fix some slate from Topps. The brazilian stuff they used to sell was cheap and OKish but now it's coming from India and it is complete and utter cack.

 

[PHG Dave]

In the case of natural split slate tiles (or sandstone & limestone ) Calibrated is a term used to describe when the tile or paving has had some form of processing carried out to its back face to reduce the variation in thickness caused by it being naturally split, as opposed to sawn/machined.

It cannot give you totally uniform thickness due to the fact that you still have a natural split top surface (otherwise referred to as a riven top surface).

The 'calibration' of the tile could be as little as the use of a sanding disk to take of the worst of the peaks as in typical Indian or Chinese slates (+/-3mm or more!) or a proper machined flat back surface as in a good Brazilian slate (+/- 1mm).

As far as i am aware there is not a controlled standard of what the thickness tolerance should be on these types of material, always check with your supplier before buying and ideally see the variation yourself to avoid nasty suprises.

 

[advancetiling]

mrs stone website do a nice brazilian slate,recently did a large job with them,pretty uniform size and brilliant quality for the price

 

[DHTiling]

In the case of natural split slate tiles (or sandstone & limestone ) Calibrated is a term used to describe when the tile or paving has had some form of processing carried out to its back face to reduce the variation in thickness caused by it being naturally split, as opposed to sawn/machined.

It cannot give you totally uniform thickness due to the fact that you still have a natural split top surface (otherwise referred to as a riven top surface).

The 'calibration' of the tile could be as little as the use of a sanding disk to take of the worst of the peaks as in typical Indian or Chinese slates (+/-3mm or more!) or a proper machined flat back surface as in a good Brazilian slate (+/- 1mm).

As far as i am aware there is not a controlled standard of what the thickness tolerance should be on these types of material, always check with your supplier before buying and ideally see the variation yourself to avoid nasty suprises.

Not only our Wetroom guy but a stone importer, so knows his stones..

I would have just laid the slate no probs as quite a few good tilers on here would.. Some calibration can differ quite a bit as stated.. +/- calibration can vary quite a bit depending on material/suppliers and quality.

I think your tiler is being fussy or cannot lay slate..

 

[choffer74]

Hi,

I've just been looking at these brazilian state from Mrs Stone - would you recommend them for a diy'er? this will be the first lot of floor tiles i've laid. Done wall tiles before. We got a sample from mrs stone yesterday and they look fantastic. Would love to lay them but getting a bit worried about all the things that might go wrong!

 

[Del W]

Welcome to TF. Slate can be very difficult unless youve got a lot of diy tiling under youre belt.If you want to have a go ,theres plenty of advice here.

 

[Time's Ran Out]

Hi,

I've just been looking at these brazilian state from Mrs Stone - would you recommend them for a diy'er? this will be the first lot of floor tiles i've laid. Done wall tiles before. We got a sample from mrs stone yesterday and they look fantastic. Would love to lay them but getting a bit worried about all the things that might go wrong!

1st of all :welcome:.

I don't know the supplier of your sample slate (ie not dealt with them before) but if I was sending out a test piece it would be of the highest quality.
Then again it's what they have in stock and will send on receipt of your money that counts.
We are at present on a 75sq mt Chinese Slate job the customer purchased off the internet and cost was the ONLY factor. The inside room was tiled with 35sq mts of material chosen for the quality and colour and the remaining 40sq mts to be used outside on a patio (possibly by others!)
IMHO Slate is not a product I would recommend for your first floor tiling experience and a question I often ask is 'will your attempt add value to your property?'
However if you are a competent DIY enthusiast then start a new thread with your questions and you will receive good advice from the Best Tilers Forum.
Good Luck.

 

[widler]

if you lay these,i would take my time,make sure your floor is bob on,mine were laid on a floor which god knows who concreted years ago before i bought it,in a house which was built in 1860ish,i had no choice to lay over this 'concrete' due to heights mostly and money.these are the mrs stone calibrated riven slate tiles which i laid,600 x 600,to be fair they ranged from about 7 to 15mm,but cost me £12.50m2,bargin,and were a challange to lay,but looked then and still look now great(they are in my album,my extreamly lucky daughters house,to have such a wonderful dad)
:smilewinkgrin:

 

[The Legend; Phil Hobson RIP]

Hi Widler, is that a closer in the floor?

 

[DHTiling]

Ooow looks like a closer to me.. wonder why..?

 

[doug boardley]

...deffo a closer...

 

[Del W]

Dave, can you check your pms please.

 

[Tabby Cranks]

Hi Widler, is that a closer in the floor?

I'm going for two different substrates and a movement joint.

 

[Ian]

A ply cover over a channel that contains pipes, that's my guess!

 

[widler]

ha ha,well,right,erm,i hoped no one would spot that,you see,what i did,was,erm,right,i also bought some 600 x 300 for the bathroom floor and had a few left over,so being a clever dick as i am,i thought,"well,considering this is going to be the dining room area i think i will split it so its like a differant area":rolleyes5:

the day after i thought,what the blinking hell did i do that for,oh well,the women won't notice,tich,as if the women will notice. well the gob full i got off em all,even the 5year old noticed

im acually sat here waiting for the verbal abuse,im all embarressed:smilewinkgrin:

 

[The Legend; Phil Hobson RIP]

No need mate, I thought there must be a reason as long as everyone is happy:smilewinkgrin: some very keen eyes on here.

 

[choffer74]

i will certainly be taking my time!
Good thing is the kitchen floor seems pretty flat, and its only about 5 sqm with very few awkward spots.
I spoke with someone and mrs stones floors and they said the calibrated brazilian slate should be 10mm with little variation - should i be taking this with a pinch of salt? as you mention 7 - 15 mm

love your floor. Is that white grouting? we were going to go for a grey grout but not sure now.

 

[widler]

i will certainly be taking my time!
Good thing is the kitchen floor seems pretty flat, and its only about 5 sqm with very few awkward spots.
I spoke with someone and mrs stones floors and they said the calibrated brazilian slate should be 10mm with little variation - should i be taking this with a pinch of salt? as you mention 7 - 15 mm

love your floor. Is that white grouting? we were going to go for a grey grout but not sure now.

hi mate,not white,it was mapei,gray i think,it is quite light though,some bleach i think by the daughter mopping up aint helped

also i laid the left over tiles today from that floor last year in a little gite,and they defo differ in thickness,more than a few mill.
also,when you lay,you will get lipping if the tiles are riven,sometimes with these tiles it can't be helped,but if it looks to much in places,you can spelch it off a bit with a small thin chisel,after its set solid of course. hope all goe's well with it

 

[choffer74]

well all tiles ordered today - went for the granfix grey. Will let you know how i get on - although i expect i wont start on the floor for a few weeks yet. Got the wall tiles to do first!!

 

[BWTiling]

Calibrated Slate should relate to all Dimensions including Thickness! If got from a decent supplier you can pick up Honed, Polished, Calibrated Brazilian Black Slate for around £32-£33 per m2, which are around 10-12mm Thick throughout and 600 x 400 if I remember correctly? Have used them on many occasions and they come up perfect every time!

As already mentioned, a Good Tiler would still be able to work with Riven Slate through grading, starting with the Thicker Tiles in the centre of the area being tiled and working outwards to the thinnest ones around the edges as this way makes the Slate easier to Cut and saves your Diamond Blades!!!...

Good Luck with it all anyway, but if you've asked for calibrated then there's no way on this earth that you should have a variation in thickness of around 10mm, that's just madness....

 

[choffer74]

well the slate tiles arrived a couple of weeks ago and they seem pretty much perfect to me! I've got no previous experience of slate tiles but for £18pm i'm well impressed

The old tile has some un-eveness. Started doing the wall tiles first but cant wait to start putting them down