porcelain floor without grout gap????

[mingualez]

Hi I gather there is a recomended 3mm bs gap. However I have these polished floor tiles I wish to lay without a grout gap,is this recomended or are there implications with expansion etc. Thanks for reading hope you can help????

[wetdec]

Not recomended really and situations where nothing is ever spilt (so cant get underneath) or dirt cant accumilate are rare. Also if porcelain the edges are more likely to chip

..

[michel]

you CAN buy 1mm spacers in some tile shops, However most grouts only support a minimum joint of 2mm.

buttjoining tiles is not reccomended due to expansion!

[doug boardley]

whatever the situation (is there any under floor heating, plywood or concrete etc substrate?) I wouldn't recommend anything less than 3mm grout joints. My own personal preference is 4-5 mm joints. What size are your tiles, really need more info for the guys to give an informed opinion. imo
Doug

[Jo Kelly]

Are the tiles rectified (machine-cut straight edge)? If they are, they are designed to be fit with a minimal joint (i.e. 1mm) but I would take into account the chances of movement through flexing or temperature changes to be on the safe side.

Mapei's Keracolour FF is suitable for joints from 0 to 6mm and particularly good with polished surfaces. If you decide to use a minimal joint, I would allow your adhesive extra time to set before grouting.

Jo

[deanotile]

Are the tiles rectified (machine-cut straight edge)? If they are, they are designed to be fit with a minimal joint (i.e. 1mm) but I would take into account the chances of movement through flexing or temperature changes to be on the safe side.

Mapei's Keracolour FF is suitable for joints from 0 to 6mm and particularly good with polished surfaces. If you decide to use a minimal joint, I would allow your adhesive extra time to set before grouting.

Jo

This is good sound advise and the only thing I will add to it is if you go for a 1mm joint then leave an expansion joint around the perimeter of the room.

[mingualez]

Hi thanks for your reply's
The tiles are polished porcelain, machine straight edge cut. 300mm x 300mm. approx 8mm thick.
I would rather of butted them up for design reasons but as the floor is chipboard with pipes underneath, I guess it is subject to movement and I think I will be better off with a 3mm gap. I wonder, is there a dye or grout that comes in black or cream as the floor will be black and cream check and I dont think grey or white will be complimentary!!
I read in another thread that pva is no good for sealing if using porcelain, just wondering why that is.Also when grouting a polished floor, what are the scratch implications on the surface and should there be an alternative application method.
Please excuse my questions but i have limited tiling experience and with ceramic only!!! Thanks in advance>>>>>

[Jo Kelly]

Mapei range of grouts come in 26 different colours so take your pick over what you want - you could use either black (120 Nero) or cream (130 Jasmin). PVA would be too thick to seal the tiles as the pores in the tile aren't big enough so you need something like HG Stain Protector. If you are doing a chequerboard effect I would recommend 2 coats, 1 prior to fixing, 1 prior to grouting. The biggest problem normally with polished porcelain is grout bleeding into tiles when using a different colour so ensure you seal the edges which is easiest done when tiles aren't fixed and then seal again before grouting.

You shouldn't find the tiles scratch if they're polished porcelain - its normally glazed tiles that will have problems with scratching.

Jo

[mingualez]

Thanks for the reply. I was refering to the sub floor in regards to the pva sealent/key ie chipboard,sorry didn't make myself clear there!!!To be honest porcelain seems a royal pain in the butt. think i'll be taking the tiles back and sticking with the ceramics..lol

[grumpygrouter]

There is nothing wrong with using porcelain tiles, just the fact that you may have wanted to lay without/minmal grout joint. Even if the tiles are rectified, they will still not be EXACTLY the same size, don't be fooled into thinking they would be.

PVA has no place in a tiling installation. Tiling straight onto chipboard can be done with appropriate adhesives, but it is much better to prepare the floor by over boarding first. Depending on the adhesive you choose to fix the tiles with would depend on wheather the floor would need priming or not. BAL for instance stipulate sealing the back and edges of ply before laying with BAL Bond SBR and NO primer on the tiling surface. Ardex on the other hand, say to seal back and sided with polyuerthane varnish and prime tiling surface with P51 primer.

What ever you choose, check the manufacturers recommndations carefully.

1 last thing, if you go for a 1mm grout joint, it is very easy to lose it because of variances in tiles sizes as stated before.

[mingualez]

thanks GG. the fact is I didn't realise that the pocelain tiles needed to be seeled. Nor did I realise the edges would be prior to laying should I use a colour grout to prevent bleeding of colour into the tile. Maybe I was naive , but I thought that the tile (wicks polished porcelain) would be a straight forward job ie prep surface lay tiles grout ,job done, but it appears not to be the case. As I have just one wc/bathroom time is a big issue unfortunately . Thanks for your help...

[grumpygrouter]

Hi Minguelez, you should not have a problem with grout colour "bleeding" into the edges of porcelain tiles. They are virtually impervious to moisture, so bleed should not be a problem. I am happy to be corrected though should I be wrong....

The top surface should be sealed as there will be microscopic pores, that would have been opened up by the polishing process, that can grab onto the grout, making it difficult to clean off. This is why they need sealing.

Pilkington recommend sealing their polished porcelain before fixing, and really this may be a good idea if you are not sure how your particular tiles will react.

[Jo Kelly]

thanks GG. the fact is I didn't realise that the pocelain tiles needed to be seeled. Nor did I realise the edges would be prior to laying should I use a colour grout to prevent bleeding of colour into the tile. Maybe I was naive , but I thought that the tile (wicks polished porcelain) would be a straight forward job ie prep surface lay tiles grout ,job done, but it appears not to be the case. As I have just one wc/bathroom time is a big issue unfortunately . Thanks for your help...

I hope I haven't put you off using porcelain - it is a very good product and laid right, a polished porcelain will look stunning. Most GOOD QUALITY porcelain doesn't require sealing but the polishing process opens the pores of porcelain and the manufacturers will normally recommend sealing if you are using a different coloured grout to the tile. I have used HG Stain Protector before and it doesn't take long to brush over the tiles (you only need a thin coat) and it is quick to dry (1-2 hours). There are other products, such as Lithofin Stain Stop, that are also very good but I've never used.

[mingualez]

So basically if I seal the tiles before grouting it should be ok. Do I have to use an edge sealer or will the same product i use on the face do the job?? Also, I take it that any adhesive that gets on the face whilst laying will stain also???Perhaps as I only have
10m to lay it might be worth sealing the tiles before laying, a pain but maybe worthit for a messy novice???
Jo K, I would rather your opinion than have no feed back at all, it is well appreciated!!!

[Jo Kelly]

Thanks! Just remember it is only an opinion!

You can use the same product to seal the edges. Polished surfaces tend to wipe off easily but I tend to work on "better safe than sorry!"

[mingualez]

where is the best places to buy sealer and I understand the cheeper tiles such as mine require a wax layer to be removed???is that product easily available too and are they both resonably priced products ie in-expensive???

[Jo Kelly]

Most tile stores will have either Lithofin or HG in stock so I would try there first - HG Stain Protector normally comes in 1 litre bottles which should be plenty to cover what you want. I am unsure about the wax layer - I haven't come across a tile with it yet - only those with wax strips to protect the surface and the manufacturer just recommends wiping the tile with a clean cloth to remove the strips and then using HG Stain Protector before grouting to stop anything affecting the areas where the wax has been.

I have sent you a PM about the HG.

Jo

[grumpygrouter]

Thanks! Just remember it is only an opinion!

You can use the same product to seal the edges. Polished surfaces tend to wipe off easily but I tend to work on "better safe than sorry!"

If you seal the edges of porcelain tiles, do you not have problems with the grout getting a "grip"?

[Jo Kelly]

I never have done - I've sealed it the same way I've sealed natural stones around the edges. I've always used Mapei Ultracolor Grout and never found it to be a problem.

When polished porcelain started to get bigger in the market about 6 years ago, I dealt with a few chequerboard floors that had been grouted in black and the black had bled into the white tiles. It looked awful and considering the tiles were about £45 a sqm then, the customer was extremely unhappy. It was before much was really known about porcelain and some requirements to seal it. So now, when using a chequerboard effect, I personally would seal edges and surfaces.

[TilingLogistics]

posted on wrong thread

[deanotile]

Well! What a shock!!! Do we have a definitive answer? I have spent close on £9,000 on training spread between the UK, USA, Germany and Italy

Kev

And you still know nothing

[TilingLogistics]

And you still know nothing

Dean your right!!! Lots to learn!!! I aspire to be like you eventually when I gain the experience you have. Massive company, VAT registered, Limited Company, employing all those people, flash house & car. I might get there though one day in the future.

Kev

[deanotile]

Dean your right!!! Lots to learn!!! I aspire to be like you eventually when I gain the experience you have. What you

Kev

want to be an argumentative ******?

[Dave]

want to be an argumentative ******?

DEAN!!!!!!!....chill

[groucho]

Lithofin do a special sealer just for polished porcelain called FZ which you put on after you grouted. I use a hand held buffer brings the tiles up great

[Researcher]

In China, the majority of residential properties use porcelain tiles and almost exclusively large format tiles 800mm x 800mm to 1000mm x 1000mm, although some older properties have 600mm x 600mm. What I have noticed is that the joint widths are always between 1mm to 2mm! Although I have not seen a 0mm joint yet.
I would have thought porcelain was quite a stable material, in that it offers little expansion, can anyone clarify this?
Over here manufacturers tend to recommend 3mm to 5mm, I often wonder why, perhaps it's cautionary or just inexperience? I guess in China, they've had decades of experience, in a market where porcelain is the primary tiling material.
Just came back from a sourcing trip, popped into a few of the local tiling stores (the whole street is populated with tiling stores: small and large! - certainly different from the UK! - another street is full of lighting stores!) Anyway, a very good quality branded tile (medium traffic, polished porcelain) at 800mm x 800mm is going for approximately 70 pence per tile! The mind boggles!

[365drills]

I've also seen a lot of stone laid with zero to 1mm abroad.

But the key difference between property abroad and your standard UK house is that 99% of property abroad is a concrete structure reinforced with rebar.


Most properties abroad are built in the same way as commercial building:
Concrete and Rebar!

Most UK houses have a mix of wood (joists) and floorboards. (planks or chipboard).

The tendency for the substructure to flex in the UK is high.


Most UK houses have rather a lot of wood! - And that moves..

Abroad they are laying tiles using a sand and cement mix onto a reinforced concrete floor / wall. So movement is unlikely. Unless you count earthquake and Volcano...

Even your standard Spanish Villas tend to butt-up the tiles without a grout joint and it seems they follow the same logic that they are tiling onto solid concrete.



But I do sometimes wonder why we space tiles in the UK if tiling onto a a solid structure. (habit maybe?)

[whitebeam]

British standards tend to sway tilers views