Indeed that is the question being asked frequently.
Our advice is to always seal it. Even if it is for outside use, it is always necessary to seal specially to avoid staining the stone when grouting. However there is a proper sequence for sealing that should always be observed. After the tiles have been properly washed dried and laid, before grouting, the tiles should be sealed. It is of paramount importance to seal your floor or wall at that stage and not after grouting. By following the correct sequence will avoid staining the tiles from the grouting.
It is worth mentioning that although possible to fix stained floors it will involve quite a bit of work, not to mention the extra cost with the appropriate products.
Obviously the professional tiller will no doubt know this. However, during this climate of credit crunch, more and more customers have a go at it themselves, so our advise is to get as much information as possible to make sure that you will have a floor or wall that will make you proud rather than bring you shame!
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