Importance of sealing stone

[Qwerty]

I was contacted by a previous customer in the week who was not happy with how his fireplace had been sealed. He was concerned with the quality of the sealer they had applied and wanted me to reseal it. I tested it and after a few minutes it had soaked up some water. I told him that I would seal it with LTP Colour Intensifier but use an off cut to test first.

Here are the results of one half sealed and other not with a tablespoon of water after just 5 minutes........

After 2 hours the unsealed part had absorbed all of the water but the sealed half was totally unchanged. A quality sealer is essential with stone (along with correct application technique).

 

[Mr Tiler]

What was the reason for unhappiness with original sealer? Was there an issue or just simply the tin didn't look a good sealer? Cheers

 

[jonnyc]

not sure if this is the right test to make.
what you have is your sealer creating surface tension which is wanting to reject water even after only 5 mins as you say.
but that surface tension could be eradiacted with a brief scrub with a nylon pad.
i am not an expert on this but i am very experienced with many sealers over last 25 years.
i believe that the key is seeing how the stone is sealed after at least 24 hours .
even then the surface tension will be taken away when grouting but hopefully one can see difference between sealers at this point in time only.

 

[Qwerty]

not sure if this is the right test to make.
what you have is your sealer creating surface tension which is wanting to reject water even after only 5 mins as you say.
but that surface tension could be eradiacted with a brief scrub with a nylon pad.
i am not an expert on this but i am very experienced with many sealers over last 25 years.
i believe that the key is seeing how the stone is sealed after at least 24 hours .
even then the surface tension will be taken away when grouting but hopefully one can see difference between sealers at this point in time only.

I fully appreciate that jonny, it was a quick test to demonstrate to my client the importance of sealing as he is worried cup ring marks will be left on the stone. Just shows how well the sealers work and how important they really are