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Fixing mortar joints on cultured stone ???

3624 Views 2 Replies 3 Participants Last post by  clasact
My grout/mortar joints did not come out as I would like due to mix-matched shades when it all dried.
I have been told there is a slurry type mixture that you can coat all the joints (like with a paint brush) to blend everything back together.
They thought the mix was mortar and Durabond and something else.
Does anyone know about this or a way to fix this problem I have?

Thanks so much.
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Mortar joints

Typical joint in brick or stone is much deeper than it is wide. In fake stone, the joints is as deep as it is wide, or often, wider than deep. This leads to the mortar drying out very fast, not leaving enough water for the rehydration reaction that the mortar needs to properly set. In addition, the concrete that the fake stone is made of also absorbs water like a sponge.

Typical symptoms of this condition include the mortar hardening up within a couple of hours, instead of a day or two. The surface may be dry, white and powdery so that the color of the mortar never actually develops. Depending on the width of the joint, which varies in a stone application, the color will vary depending on the rapidity of the drying out.

On exterior applications this a serious cause for concern as the mortar will crack over time, it will not be properly adhered to the adjoining fake stone and generally become a poor water barrier. The only real fix is to remove all the mortar and start over. Where I have caught contractors doing a poor application, they have been able to scrape out the offending areas of mortar fairly easily, since they were doing it only several hours after they started.

I have never done the application that you describe as for my projects that would not be acceptable, the improper application of the mortar would cause the work to be rejected. There are concrete color stains available out there, Sherwin Williams comes to mind.
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Woody I had a similar problem when I put up some cultured stone around my windows.I had run out of the original mortar and just ran out and got another but it was a different brand and did not blend well with the tint.When it dried it was much lighter but I had cleaned out my joints to about 1/2 an inch.I talked it over with the supply house and was told to use the same mortar as I started with and mix up a few small batches and let it dry till I got the right shade>I did so and wrote down the amount for each mix or tint.Then filled the joints in a little but not all the way so it all matched.I then coated it all with sealed /restorer as recommended(I highly recommend this part).It came out pretty darn good if I say so myself,so you might want to give this a try.I have never heard of what your talking about and it was never mentioned At the stone supply
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