Issues with not sealing Marble before grouting.

[charlie101]

Hi Guys

I have a stone tiler fixing some carrara bianco in my bathroom.
He says it's not necessary to seal the tiles before grouting and that he's done it many times without problems (He has 25 yrs experience in stone work)

However you have previously recommended to me that the tiles be sealed prior to grouting and I have read that recommendation several times in other posts and on other forums.

Can you please tell me what the issues or risks are with not sealing before grouting so I can make the call. (He will be using a light grey flexable grout)

I have already purchase the Dry Treat Meta Creme but I could pre-seal with OLE-REPELLA.

Thanks in advance

 

[DHTiling]

Your tiler is right.. Not all stone needs sealing first.. we advise the DIY to seal first to prevent mishaps but a tradesman knows what he can and can't do with stone ...

So yes, it is ok to seal afterwards with certain stones.

 

[diamondtiling]

All natural stone should be sealed prior to and after grouting, you may end up with grout haze or staining to the surface of your tiles, your fixer should already know the potential problems.

 

[diamondtiling]

Your tiler is right.. Not all stone needs sealing first.. we advise the DIY to seal first to prevent mishaps but a tradesman knows what he can and can't do with stone ...

So yes, it is ok to seal afterwards with certain stones.

Well that just put me in my place Dave, I was under the impression that its best to seal all stone mate?

 

[DHTiling]

All natural stone should be sealed prior to and after grouting, you may end up with grout haze or staining to the surface of your tiles, your fixer should already know the potential problems.

Surprises me you saying that..

 

[DHTiling]

Well that just put me in my place Dave, I was under the impression that its best to seal all stone mate?

We do advise members who are new to stone work to seal first.. but travertines and some marbles are fine.. BUT this also depends upon grout colour.. but yes you can seal afterwards.

 

[diamondtiling]

We do advise members who are new to stone work to seal first.. but travertines and some marbles are fine.. BUT this also depends upon grout colour.. but yes you can seal afterwards.

My reason for advising to seal all stone came from a problem I had some 8 years back, it was a light veined marble and the rep said it was ok to seal after grouting and this is what I did only to have a finish that was far from perfect. When the company sent another rep he advised that the marble should have been sealed first so that is what I do all the time now just to be sure. It saves me having to spend hours trying to rectify a problem that I should have avoided in the first place.
Would it not make better sense to seal first Dave?

 

[DHTiling]

Anyone who is unfamiliar with certain stones then always seal first.. but the OP said it is wrong for his tiler and if his tiler is competent in stone tiling then let him do his job..

Apart from slates and certain limestones.. i don't seal till after.. although around 90% of my work is stone.. so as a stone fixer i know what works for me as they say..

Just to add if this was a members of the public then yes seal first..


Dom.. do you seal unfilled trav etc first..?

 

[diamondtiling]

Seal unfilled Trav first............you trying to catch me out there Mr Howe?

I dont seal unfilled trav prior to grouting because it would cause problems with the grout filling the holes.



:smilewinkgrin:


I have only fitted unfilled a handle of times and my first question to the rep was regarding sealing.

 

[charlie101]

Thanks for your replies.

I'm confident my Tiler wouldn't do anything to substantially degrade the finish.
However it's not uncommon for someone to go with a solution which is easier for them rather than what best for the finish.

For example he already tried to avoid polishing the external corners (there are a lot of them).

My issue is that we have chosen heavily veined Carrara CD and I don't what anying to decrease the contrast between the grey veining and the off-white background.

Could the grey grout leave a residue or light staining in the marble which could reduce the contrast?

 

[DHTiling]

If using a light grey grout and if the veins are broken in anyway.. then yes seal..as this will help clean down... but it is common to seal afterwards is all i am saying..









Dom.. Sealing unfilled as you say stops grout grab.. but in theory you grouted before sealing and no probs.. so you see what i mean.. lol lol.. Take each stone at face value..

 

[Dan]

Bump

 

[jonnyc]

Before all these sealers came out, wo years ago plus when I did a lot of marble never sealed tiles before or after grouting . You have to know your stones/ marbles though