Do I need to seal unglazed PEI 5 porcelain - TilersForums.com

[Filip]

I think I have decided on my tile for an outdoor but mostly dry space protected on 3 sides but can have rain blown in - see picture. The tiles are PEI rating of 5 this full bodied porcelain and come unglazed. I then start reading about stains and sealing and start to doubt my choice (haven't got them yet ) the fella in the store says I do not need to seal, they are these . I have brought a couple to test and have a range of stuff on them to see if they do stain.
The yellow line marks the extent of the roof coverage

 

[Filip]

Ok I have come back to answer my own question but would still appreciate an experts view.
I have done some tests with grass,coffee,oil(olive) sharpie pen, biro, vinegar, and left it on for 18 hours. And none it has left any mark whatsoever. I am also ding a water absorption test and so far after 18 hours there has been no gain in the 108g starting sample weight

View attachment 98669

 

[Andy Allen]

Your tiles are probably glazed porcelain and do not require sealing.

The only porcelain tiles you need to seal are polished porcelain tiles.

 

[Filip]

These are the ones
The second slideshow picture on the page says

• Porcelain Floor Tiles
  Perfect for areas of increased footfall, these hard wearing unglazed porcelain floor tiles will stand the test of time.
  

 

[Filip]

Just seen that my picture was not there with my test tile, here it is. I put a few drops of water on it and then added instant coffe very strong.

 

[Andy Allen]

I must be missing something, cant see anything that says the tiles are unglazed, just full body porcelain..

 

[Albert]

The tile is Vitra dotti and is unglazed. I thought all full body porcelain
was unglazed

 

[Filip]

The only place I can see it says it is on the second slideshow picture - here is a screenshot

 

[Lithofin BOB]

Good test, haven't heard of any external grade porc that requires impregnating. Maintain only

Check your grout release on install, on a spare tile maybe, with the extra texture. a lot of the external boys are using bal temp sealer if they have problems to aid release.

 

[Filip]

Thanks for the grout heads up. I have some Tilemaster 3000 in charcoal and will do a test with that.

 

[Filip]

Ok thats the end of the water absorption test because after 24 hours I want my pint glass back.
Result - no weight gain.
2nd result - beer for me

 

[Filip]

Ok I have now done a grout test and that is fine, infact nothing seems to stick to this tile, I do actually need something to stick to it - namely adhesive. So I have done a grout test on the back and that is a lot more difficult to get off. Picture attached. The tiles are marked on the back Made in Turkey - is that good ?