Large Porcelain: 1200 by 600 vs. 600 by 600

[Ripmaster]

All,

per the excellent advice i have received in other threads I thought I would canvas some opinions.

120 Sq M of "common areas" of the house (Entrance lobby 5*5.5m , corridor (1.25m * 13m), lounge (5.4 * 12M) and and utility room.



The current favourite tile choice is a 1200*600 rectified porcelain (see pic). It is also available in 600*600 which I am sure from what I have discussed with various tilers would be "easier" to install. However even with a 1mm grout line I am still not 100% convinced it will look "as good" (all subjective I know) with a square tile running along a rectangular hall through to lounge. Substrate is a (pretty level and flat to be fair) anhydrite screed with UFH (pipes set at 100mm centres).

Any comments/advice feedback welcome on the pros and cons of either size. Before I make final decision I'd like to know if there are any issues (aside from asthetic) which might come into play.

Thanks in advance.

rm.

PS: I won't say that larger ones will be quiker, I already know better than that

[doug boardley]

tile size is a personal preference imo, but the anhydrite screed needs to be prepared properly. The laitence (white residue) needs removing and then at least two coats of acrylic primer need applying in opposite directions to stop sulphate fro the gypsum causing ettringite failure that would lead to your tiles de-bondng.

[david campbell]

not keen on the idea of using 1mm grout lines especially over ufh,the 1200 x 600mm will give a lot of wastage on the hallway if it's 1250 wide as these will probably need to be centred giving you 2 cuts of about 623/624mm,therefore losing almost half a tile each time. personally i would opt for the 600 x600mm

[Ripmaster]

not keen on the idea of using 1mm grout lines especially over ufh,the 1200 x 600mm will give a lot of wastage on the hallway if it's 1250 wide as these will probably need to be centred giving you 2 cuts of about 623/624mm,therefore losing almost half a tile each time. personally i would opt for the 600 x600mm

Idea would be to place side by side in the corridor as it runs perpendicular to the entrance lobby/hall. So 2*600 side by side running lengthways. Re-masured and hallway is actually 1.22 so that should work well with 8mm or so either side for expansion.

If 1mm grout lines are an issue with UFH (I presume for expansion issues) then I'd probably stick with the 1200*600s.

Cheers.

[Phil Hobson]

I agree with above but would stress the minimum joint is 3mm, when fixing large format floor tiles. I would go for the 600x600 personally

[grumpygrouter]

I agree entirely with Phil on this too. 1mm with UFH - suicide in my opinion.

[TheWrightTiler]

agree there with grout size 3mm is min id go for, 1mm is mad with ufh, just my thoughts and others may disagree

andy

[Terry Cottar]

I don't so much disagree with the 1mm grout joint because of the UFH but what you will find is those tiles that size will have planimetric tolerances (In laymans terms the tiles will Probably have some bends in them) this in turn makes it difficult to fit them brickbond or 1/4/1/3 bond. Moreover if youre rooms are not perfect which they won't be you will have no room for error/correction with a 1mm grout joint and finally it is outside BS. BS state that the minimum grout joint should be 3mm on a floor. Finally if it is a monolithic look you are trying to achieve my advice would be to choose another material.

tel

[365drills]

It seems the gen public want to see less grout so opt for bigger and bigger tiles with less and less grout lines.

The problem seems to be that on holidays to spain etc many people see those lovely tiles with zero grout line not realising that these have been fixed with CEMENT to concrete shells which is the spanish way of home building and hotel building.

In the UK its a different (and flexible) story with half timber houses which breath and move.

I see you are between a rock and hard place. If you go for a min joint and 6mnths later it cracks then you have to go back. The only other way is to super strengthen the room, floor, wall so that movement is impossible.


In order to ensure the floors and walls for a 1mm grout line
would work the room had to be strengthened first....

[jamie B]

It seems the gen public want to see less grout so opt for bigger and bigger tiles with less and less grout lines.

The problem seems to be that on holidays to spain etc many people see those lovely tiles with zero grout line not realising that these have been fixed with CEMENT to concrete shells which is the spanish way of home building and hotel building.

In the UK its a different (and flexible) story with half timber houses which breath and move.

I see you are between a rock and hard place. If you go for a min joint and 6mnths later it cracks then you have to go back. The only other way is to super strengthen the room, floor, wall so that movement is impossible.


In order to ensure the floors and walls for a 1mm grout line
would work the room had to be strengthened first....

Spot on. I get asked more and more often for 1mm or no expansion. Just another 'phase' in tile fashions I hope!
Lets not forget either the problems with tile size variance when fixing very small expansions...gives you no tolerance over large areas..if you're unlucky with 'sizey' tiles it can throw the whole job down the pan!

[Ripmaster]

In the UK its a different (and flexible) story with half timber houses which breath and move.

I see you are between a rock and hard place. If you go for a min joint and 6mnths later it cracks then you have to go back. The only other way is to super strengthen the room, floor, wall so that movement is impossible.

[/COLOR][/B]

i'm not sure what you mean by Superstrengthen?. The property is, lets say a little more substantial than run of the mill UK cardboard boxes:

• Steel frame
• Solid Block in fill (although this is minimal as many walls are glazed) - we used a mix of 9'' and 6'' as I thought 4'' were flimsy! LOL
• Block & beam floors with 50-55mm screed on top of UFH.
• The foundations are mostly built on very hard shale, we did not have to dig down too deeping before we started hitting rock.
• Over 100 Cube of Concrete in the foundations supporting the Steel uprights in 2 to 3 meter square pillars all 2 to 3 meters deep.

Other than using Titanium for the frame, I'm not sure what else we could have done to make it stronger ;-)

I'd put money that it is stronger than that Guantanamo cubicle :-)

Strength of the structure aside, I still take on board the expansion issue and minimum grout mm. With UFH is is going to move a little without a doubt. I'm not after "no expansion' either.as can be seen in the pic, there is already a 8 to 10mm expansion joint all around the slab. This would be replicated with the tiles and covered with large skirting boards. It is just the grout line that we are considering how small we can get away with, as they do look better than larger lines, especially on large format tiles.


Anyone know a good Spanish Tiler? LOL

PS: I thought porcelain tiles needed a cement based adhesive, anyway, (due to the lack of porosity or so I was told) so not sure what is so Spanish about that.

[365drills]

I'd put money that it is stronger than that Guantanamo cubicle :-)

Maybe they will turn it into a tourist spot like Alcatraz.... If so then that's what your shower block will look like!

NB: If anyone is wondering about the use of the image - its not been ripped.
Its free-licence on a website called WikiMedia this site is for free use of images
If anyone wants free pictures its a limited resource. But you can use them for £0

[365drills]

Also meant to add that you MIGHT be alright. In my own home I strengthened everything to include the floor joists, ceiling, walls.

Even then the top of the shower cracked.



Cant see it?

Closeup.

Point is if there is any flex or give then it could affect your finish.
Lucky for me this flaw is at the top of the shower (not the bottom) so not in contact
with water. And behind the tile is a Bal tanking system which waterproofs the cubical.

But it does sound like you have solid foundations so you are off to a great start.

Yes porcelain tile addy is cement based (has additives like polymer to stop it going off so quick and give it more flex)
In other countries they just use the basic sand and cement render and work a bit quicker !

[beanz]

As the others have said, size is down to personal preference. For me, i'd like the 1200x600 laid in a brick bond with 2mm lines.

edit* I should've finished reading your post... Didn't realise they were porcelain; that might make a difference if thinking about brick bond. Worth checking them for flatness.

[Ripmaster]

They will be straight lines rather than brick in any case. Thanks.

[Rich]

Would like to agree with most of the guys above, size of tile is really down to preference but the joint size is important. BS state that the min grout width is 3mm. 2mm looks better but imo you should follow the standards so that if anything goes wrong in the future, your covered.

[beanz]

Would like to agree with most of the guys above, size of tile is really down to preference but the joint size is important. BS state that the min grout width is 3mm. 2mm looks better but imo you should follow the standards so that if anything goes wrong in the future, your covered.

Does NOT following BS void your insurance? I've often wondered about this, as the standards are just guidelines and not actually rules/law, and in most cases complete overkill imho. I recently did a floor with 3mm lines because the tiles were cheap, and coming out at different sizes. Hated the finished look. 3mm lines are just too big, and look hideous!

[Rich]

Agree that a lot of it is over kill. 2mm looks a hell of a lot better but I dont think you can always go on how it looks, there is a lot more to consider. If hes going to be using ufh id want to open the joint to 3mm for expansion (BS min for any floor). Dont understand why following BS would void your insurance??

[beanz]

Dont understand why following BS would void your insurance??

NOT following BS.

[Rich]

Ahh... I see. Sorry, My mistake.

[TheWrightTiler]

just remember that if customer doesnt like final look and trys to sue etc, you will lose as your the pro not them you should know better

theres prev threads via waivers etc and they dont mean jack, id go with the 3 to keep myself right

[Rich]

Good point, just ask sir ramic about waivers!!. Whatever you decide to do, make sure you run it by the customer BEFORE you start to lay. If they dont want a 3mm joint, mention that it is in the BS and that the tiler would be legally responsible for the floor even if they sign a waiver. If they insist, then its down to you to decide.

[beanz]

Good point, just ask sir ramic about waivers!!. Whatever you decide to do, make sure you run it by the customer BEFORE you start to lay. If they dont want a 3mm joint, mention that it is in the BS and that the tiler would be legally responsible for the floor even if they sign a waiver. If they insist, then its down to you to decide.

Let's not over-educate the customer. Most would not know this, and wouldn't even think to go down that road, as you were working to their instruction. They would assume the waiver was enough to cover the tiler.

[Ajax123]

All,

per the excellent advice i have received in other threads I thought I would canvas some opinions.

120 Sq M of "common areas" of the house (Entrance lobby 5*5.5m , corridor (1.25m * 13m), lounge (5.4 * 12M) and and utility room.



The current favourite tile choice is a 1200*600 rectified porcelain (see pic). It is also available in 600*600 which I am sure from what I have discussed with various tilers would be "easier" to install. However even with a 1mm grout line I am still not 100% convinced it will look "as good" (all subjective I know) with a square tile running along a rectangular hall through to lounge. Substrate is a (pretty level and flat to be fair) anhydrite screed with UFH (pipes set at 100mm centres).

Any comments/advice feedback welcome on the pros and cons of either size. Before I make final decision I'd like to know if there are any issues (aside from asthetic) which might come into play.

Thanks in advance.

rm.

PS: I won't say that larger ones will be quiker, I already know better than that

Looking at the surface I would say that the screed needs a sander over it before you tile. I would prefer a water dispersible epoxy primer rather than acrylic or unless you are going to use a gypsum compatible adhesive (one which won't react). PM me if you need some product details.

Underflor heating needs to be comissioned as well - these links might be useful to you.

http://www.gyvlon.co.uk/Drying%20Gyvlon%20Screeds.pdf

http://www.gyvlon.co.uk/Floor%20Cove...Guidelines.pdf

[Ajax123]

Does NOT following BS void your insurance? I've often wondered about this, as the standards are just guidelines and not actually rules/law, and in most cases complete overkill imho. I recently did a floor with 3mm lines because the tiles were cheap, and coming out at different sizes. Hated the finished look. 3mm lines are just too big, and look hideous!

No failing to follow BS would not void your insurance. Negligence however may well do so. It would certainly make void any warranty from the manufacturers. British standards are (In the UK anyway) simply codes of practice based on the industry consideration of what should be done. They are usually written by the relevent trade associations which they represent. There are many anomalies in these standards which if they were followed to the letter might result in issues. There are also many standards which talk about the same topic from differing points of view and which conflict with each other. BS5385, BS8204 and BS1264 all have conflicting advice about screeds for example. There are many new and innovative materials used in construction nowadays which are considered proprietary materials as they are not covered in any current standards. In Europe it is different as most of the standards in Germany and France are considered legislative.