Tiling kitchen floor white haze/ do I need to seal!

[Daisy0701]

Help!
DIY isn't my strong point, so after my dog ate the Lino (yes my dog really did eat my Lino) in the kitchen I decided to tile the floor. As if it was that easy.

I chose these tiles: http://www.diy.com/departments/magm...31_BQ&ef_id=VrcwFgAAAX-UAE2K:20160209105449:s

And a charcoal grout.

The end product looks like this:

The grout has dried white near enough, and the tiles have a haze that I have scrubbed to no evail! They are porcelain unglazed tiles... To seal or not to seal. I have read and been told so many conflicting arguments on if they need sealing. Or not.

I am hoping someone will be kind enough to help a young lady in DIY distress and point me in the right direction.

Sealer? Revivor? Rip it up in rage?

Thanks

 

[MrDIY78]

Unfortunately you have fallen for the same trap as I have with my bathroom it seems!!! The trick is to seal on the BACK of the tile as well as the front, it can suck adhesive through the tile. You also need to seal the tile before grouting or else it does what you have and I have.

I've tried acids of different types, and nothing has worked I'm about to rip it all out and get new.

 

[Daisy0701]

Thanks for the reply! Ohh no, I really didn't want to rip it out. But it seems it's the only way... Disappointed!

 

[Paul C.]

Nooooo.......... I don't agree.

These tiles are an unglazed porcelain. This means they have a moisture absorption rate of <0.5%. Therefore putting a sealer on the back of the tile will drastically reduce the bond of the adhesive. The sealer would not be able to sink into the tiles and will therefore giving you a barrier between the tile and the adhesive. Your tiles will lift within months.

There is no need for the tiles to be lifted.

It looks to me that there is no way that grout is charcoal and if it says charcoal on it, the powder inside is incorrect. If it started of as charcoal and dried lighter, there is a mass of salt and sulphates in that you will find impossible to clean off and is an extremely poor quality grout. If you can get a sheet of White A4, tip some of the dry powder on and post a picture, we'll have a look and see. It should be almost jet black. Also if you can post a picture of the bag, that will also help.

That grout will need removing with a grout rake or something similar to a Dremel with a grout Removal attachment. The next step is to get the haze off the face using LTP Grout Stain Remover, to prevent contamination of the new grout. Get yourself a new grout that is efflorescence free, such as the Mapei Ultracolour in either Nero (which is Jet Black) or Anthracita (Very Dark Grey to Charcoal).

Any part or full bags of the old grout you have left, you can then take back to where you got it from, open them up, tip them over their counter and demand your money back.

 

[Daisy0701]

Thanks for your reply! I will give this a try, and take some pictures of the grout packaging. It did start out darker, but dried like the above picture!

0.05% absorption- Does this mean that the tiles do not require sealing at all?

 

[Paul C.]

no they won't. The face will be produced with a nano-seal applied at the factory to close any micro pores that occur during the manufacture. However because of the rough texture, it could be worth you applying a temporary sealer like the BAL Protective Sealer, to make the grout easier to clean off.

Other more permanent surface sealers are available to aid cleaning, but they tend to give the tile a permanent wet "just washed" look. These bond to the surface and don't rely on a porous surface to stick. But bare in mind that these can scuff and will need to be re-applied every 2-4 years depending on the cleaning method and foot traffic, so are more of a personal preference than a necessity.

 

[Paul C.]

One other thing I should point out, is that the biggest cause of grout showing white patches is by adding too much water to the mix. This is what draws the sulphates to the surface as it dries. If the grout you bought was black when it started, this is a possible cause.

Sometimes when mixed as per the instructions, the grout can be stiff and hard to work with. Some people add extra water to make it easier, but my advise would be to persevere with the stiff stuff and don't be tempted to wet it down.

I'm not saying this is a definite cause but its one possibility you can count out if you did it as per the instructions.

 

[MrDIY78]

Interesting about what you said, I've spoken to two tilers and also Tile Giant and all three, along with some searching online said the white hazing is an effect from both coming through the back as well as micro pores absorbing the grout. I don't have them particular tiles but they are a very close match.

I have used acids like mentioned including Phosphoric Acid. We took a new tile and did the sealant and it was spot on, but I'm about to do the bathroom in a different style so pulling it all up doesn't matter luckily for me.

 

[Paul C.]

Interesting about what you said, I've spoken to two tilers and also Tile Giant and all three, along with some searching online said the white hazing is an effect from both coming through the back as well as micro pores absorbing the grout. I don't have them particular tiles but they are a very close match.

I have used acids like mentioned including Phosphoric Acid. We took a new tile and did the sealant and it was spot on, but I'm about to do the bathroom in a different style so pulling it all up doesn't matter luckily for me.

Don't get me wrong it is possible on some tiles but it all depends on the absorption rate. So for example, the tiles daisy has the rate is (or should be) <0.5% (if you have any packaging left for the tiles, it may have the class which should be B1a which is the BSEN14411 classification for a dust pressed ceramic or porcelain with an absorption rate of less than 0.5%). However, for a quarry tile or natural stone it can be as high as 10-30% (sometimes more), which inevitably will be able to take in any moisture from beneath it. so any efflorescence can rise through to the surface. Glazed ceramic tiles can also take in moisture as the "biscuit" is porous. However because the surface is glazed can prevent anything reaching the face which is why it only ever happens on unglazed breathable tiles.

The biggest cause of this on a tile is rising damp which realistically, unless you have an extremely faulty batch of adhesive, is the only thing that these salts and sulphates can be presented from. So anything with a porous back may benefit from a light sealer (I still wouldn't be happy recommending doing this), but it will have no effect on an impervious tile which will cause it to form a barrier. But the efflorescence we are talking about for daisies situation is in the grout and the haze on the face which has probably only got trapped in the rivens and cavities of the textured surface but not fully ingressed in to the tile. Thats why once cleaned, a temporary sealer will be sufficient until after grouting as it will prevent the grout for getting lodged in the undulating face.

So baring in mind that this particular type of porcelain is impervious, the stain has to be from the grout on the surface to which a brick acid or specific grout remover (and a good scrubbing brush) will help clean the tile. But the question remains as to why the black grout has gone white, which I believe is still down to either a faulty batch or excess water in the mix.