# Need help, mortar bleeding through on cultured stone



## Tommysupra13 (Aug 21, 2017)

Hello and thanks in advanced for any replies. I paid a contractor to build a porch for me with pavers on top, blue stone trim/steps, and cultured stone in front. It all looked beautiful when it was first done but it has been about a month and it looks awful now. It seems the mortar has sort of melted through the cracks of the cultured stone and has left a white streaking residue all over the stone. My contractor says to try and clean it with windex and a scrub brush. I tried that, Also tried dishwashing detergent, magic eraser, shot it with the hose for an hour, no luck!! Any idea how to get rid of it or is the stone ruined? ALSO, the pavers are developing small black dots on the surface that look similar to mold. When I tried to clean it with a scrub brush and a hose it made the surface turn more of a black color. I don't understand why all of this is happening, he used name brand material that should all be sealed. Any ideas on what to do?! Thanks for any advice


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## Tommysupra13 (Aug 21, 2017)

See attached pictures


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## Tommysupra13 (Aug 21, 2017)

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## concretemasonry (Oct 10, 2006)

What kind of "pavers" are those and what are they made of (clay, concrete, ceramic, etc.)?

What kind of mortar/grout were they set in? 

Dick


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## Tommysupra13 (Aug 21, 2017)

The pavers were Cambridge with armor tech, the cultured stone was D stone Dutch quality flats. I have no idea about the mortar that he used for the cultured stone. The pavers were set on a concrete slab of and then floated with sand


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## Tommysupra13 (Aug 21, 2017)

Any idea?


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## ZTMAN (Feb 19, 2015)

Looks like your contractor used polymeric sand for the joints, not mortar. That will stain certain hard surfaces if applied when damp or wet.

First step is to find out what he used for the joints and then go from there. 

It appears your contractor has not idea how to clean the stone based on his recommendation of windex. I would contact the stone supplier and see what they recommend.

For the mold spots, I have used a product called "wet n forget" for mold stains on a brick walkway, and it worked great.


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## stadry (Jun 20, 2009)

*concrodium or smart touch, too ! the former's easy to find at the apron/vest stores*


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## Tommysupra13 (Aug 21, 2017)

Ok thanks a lot, not sure what he used I will have to ask. Is there any type of sealer that I should use to seal the pavers that you guys would recommend? Yesterday was a hot day and almost all the black spots on the pavers disappeared so I'm guessing it was just holding moisture for some reason. But still weird bc only some of the pavers had the spots. I will have to contact the manufacturer like you said and see what they say. Thanks for the help


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## Tommysupra13 (Aug 21, 2017)

So I found out for the cultured stone the contractor used thin set. Could that be the problem? He is claiming that it possibly might be from effervescence coming through the stone and that and effervescence cleaner might get it off. That doesn't sound right to me because I'm under the impression that brand new cultured stone from the factory should be sealed with something to prevent that from happening. Also the pattern of how the streaks are showing up on the stone looks like it is all coming from the joints. What do you think? Will an effervescence cleaner do damage to the stone? I still have to write to the manufacturer and find out what they recommend to do. That's my next step, but wanted to run it by you guys first. Thanks for your help


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## XSleeper (Sep 23, 2007)

Tommysupra13 said:


> effervescence cleaner


Never thought of trying denture cleaners... reminds me of the old Efferdent commercials... now with more effervescence! Lol

I think you mean efflorescence.


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## Tommysupra13 (Aug 21, 2017)

Sorry speech to text on this phone is awful yea that's what I meant lol


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## Tommysupra13 (Aug 21, 2017)

Here's some better pics


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## Tommysupra13 (Aug 21, 2017)

..............


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## Tommysupra13 (Aug 21, 2017)

This picture is the part of the stone that still looks ok


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## Tommysupra13 (Aug 21, 2017)

Any idea what the black spots on the top of the pavers could be? I'm not convinced that it's mold because it comes and goes. It seems to be moisture that is being held in and then dries out on a hot day. I thought these stones were supposed to be sealed? I've never encountered this problem especially with brand new pavers. As for the cultured stone problem I wrote to the manufacturer to see what they recommend and they still haven't answered me. Not sure what to do. This stoop is brand new and looks awful very disappointed


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## ZTMAN (Feb 19, 2015)

Put some bleach on a q tip. Touch it to the black spot. If it changes colors, its probably mold


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## splion (Oct 8, 2016)

I've got a similar project - I already placed the pavers and now I am looking for a means to cover the vertical faces of the patio, which rises ~20 inches. Can I simply place use stone veneer mortar and slap on some natural stones? The mfg says that I can't have mulch or any other material up against a cultured stone...


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## stadry (Jun 20, 2009)

*sealer for pavers avail @ apron/vest stores*


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## bob22 (May 28, 2008)

splion said:


> I've got a similar project - I already placed the pavers and now I am looking for a means to cover the vertical faces of the patio, which rises ~20 inches. Can I simply place use stone veneer mortar and slap on some natural stones? The mfg says that I can't have mulch or any other material up against a cultured stone...


Start your own thread; too confusing with two people and problems involved.


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## stadry (Jun 20, 2009)

*as bob sez, probably best to start your own thread,,, better yet, do a search - this has been addressed previously*


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## Tommysupra13 (Aug 21, 2017)

Is it safe to use muriatic acid on cultured stone ? Or will it strip the coloring off ? Any idea? Thanks


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## Canarywood1 (May 5, 2012)

Tommysupra13 said:


> Is it safe to use muriatic acid on cultured stone ? Or will it strip the coloring off ? Any idea? Thanks




Yes it will alter the color, cultured stone needs to be cleaned asap after setting, with trisodium phosphate and plenty of water.


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## Tommysupra13 (Aug 21, 2017)

My contractor used the trisodium phosphate like you suggested and he said it bleached the stone. Not good


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## Canarywood1 (May 5, 2012)

Tommysupra13 said:


> My contractor used the trisodium
> 
> phosphate like you suggested and he said it bleached the stone. Not good




That's a new one on me, unless he used Chlorinated Trisodium Phosphate, it looks like something is bleeding from those joints, causing the staining.


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## Tommysupra13 (Aug 21, 2017)

I'm not sure what he used first he used an efflorescence cleaner which was working ok with a scrub brush but only faded it, then he tried that with a power washer and nothing then he tried the trisodium phosphate and he told me that it bleached the stone. I haven't seen it yet so I'm not so sure how bad it is. And I still have no idea why the mortar is bleeding or why this is happening What would cause this? The first couple of days maybe even up to a week the stone was fine. Then out of no where the stone started developing these white streaks bleeding through. I've never seen this before and either has my contractor. He is probably going to have to redo the stone but now I'm scared if he goes that far what if it happens again !? What a nightmare !


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## Tommysupra13 (Aug 21, 2017)

This is what happened with the trisodium phosphate, it looks even worse in person all the color came off Not sure what to do at this point I think it needs to be completely redone, my contractor thinks he might be able to put some kind of a sealer over it that might give it a little bit of a wet look and maybe bring back some of the color or kind of make it so it's not so obvious This sucks!


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## ClarenceBauer (Mar 4, 2005)

After reading all the threads on this it is my opinion that the wrong pigment was used in the mortar joints / stone.
If the pigment is not a lime compatible the color will migrate with water causing a color change when wet.
Check this catalog out Kremer Pigments 
Another problem could be that a dry pigment was used and did not mix correctly with the other binders.
I can't under why the WHITE joints at the edge stone did not darken?


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## Tommysupra13 (Aug 21, 2017)

Hey not sure about the joints not darkening. That was my suscpicion from the beginning that it has something to do with the mortar not drying right or it wasn't mixed correctly. Not really sure where to go from here it seems like he is going to have to rip off the stone and start over at this point. You are probably right about the color/lime issue


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## Tommysupra13 (Aug 21, 2017)

Every time it rains the day after this happens Any idea why ? The contractor mixed sand with dry cement under the pavers and the pavers are not totally sealed with sand all around. Any chance the rain is carrying out the dry cement and pouring through the joints ? I need to figure this out before I re do the stone. If it gets re done and happens again it is going to be really bad. Trying to avoid that at all costs. This job was done about 5 months ago and the problem still exists. Any ideas please help thanks


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## Nealtw (Jun 22, 2017)

Have you read about efflorescence
http://www.delawarequarries.com/cleaners/efflorescence.html


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## Tommysupra13 (Aug 21, 2017)

Yes I tried efflorescence cleaner and it worked about 70% of the way but couldn?t get it all out. Then my contractor used tri sodium phosphate which was recommended by someone on here and it completely ruined the stone bleached it bad. So I have to re do all of the cultured stone BUT still haven?t figured out where this problem is stemming from. If it is efflorescence then where is it coming from and how do I stop it ?


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## Nealtw (Jun 22, 2017)

This sounds like a great pile of money heading for the trash. I would be mocking up a test wall to try a few products. Is this all covering a concrete deck and how old was that?


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## Tommysupra13 (Aug 21, 2017)

It?s a front porch. All brand new. If you look back in the thread you will see pictures of it. Cement slab was poured over insulation board/ rebar grills then on top of slab I have an electric snow melt system embedded in a sand/dry pack cement mixture. Then Cambridge pavers on top of the sand


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## Tommysupra13 (Aug 21, 2017)

.........


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## Nealtw (Jun 22, 2017)

Tommysupra13 said:


> It?s a front porch. All brand new. If you look back in the thread you will see pictures of it. Cement slab was poured over insulation board/ rebar grills then on top of slab I have an electric snow melt system embedded in a sand/dry pack cement mixture. Then Cambridge pavers on top of the sand


So you have pavers on the deck that allow water to get to the slab. was the slab sealed or is it absorbing water. Was the stone applied with a drainage path.


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## Nealtw (Jun 22, 2017)

Found this.
IMPORTANT TIP: Do NOT try to wash off the powder deposits with water or an acid-water solution.
Each time you try to wash the chimney and wall surfaces to remove the salts, you actually compound the problem. The water you use dissolves the salts again and carries them back into the mortar or the masonry.
The surfaces typically look fantastic when wet and you think you've solved your problem, but the white powder appears again when the surfaces dry within hours or days.
How To Stop It
To stop the efflorescence now, you must stop all water from entering the masonry surfaces. This is somewhat easy to do at the chimney and any exterior masonry walls, but far more difficult to do with the retaining wall.
If you stop the water, there is no transport medium to carry the soluble salts to the surface where you'll see them.
https://www.askthebuilder.com/efflorescence-on-masonry/


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## ClarenceBauer (Mar 4, 2005)

You stated that the pavers were placed on a dry bed of sand & cement depending on the type of cement used the problem is the Lime content.
Being the bedding mix was dry the Lime did not Slake and is know as free lime.
This free lime will migrate with water causing the white areas. The Lime being the smallest partial size will migrate and remain in the smallest crack, or crevasse. The use of TSP would make it worse. Also if a cement containing Aluminate was used in the setting bed or the making of the pavers you may get a reaction with the Lime? Take some of the White powder to a soil consultant and have it tested my guess is Calcium. A simple test is to use swimming pool PH test strips using pure water wet the white area and see what color the strips turn the darker the higher the PH which would indicate LIME.


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## Tommysupra13 (Aug 21, 2017)

This is what I suspected and makes the most sense. If this is true what are my options ? ... take the pavers off and try to carefully remove the dry sand without damaging the snow melt system, clean out and re do with just plain sand ? OR should I try to seal the pavers joints properly with sand and see if that stops the water from getting in? And what about that ?grout? type of sand sealer that they sell for the pavers is that worth trying or do you think no matter what water will still make its way in and the dry sand needs to be replaced? Thanks for the help


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## ClarenceBauer (Mar 4, 2005)

Was this a designed project or a build as you go type project? Your build was Concrete Slab, Sand, Melt system plus pavers & stone with joints grouted. If there are any Pyrites in the sand mix this could cause the dark spots. The Cement , sand , Lime & salts will cause the other problems. The design should have had a water management system to control the egress of the water. As it is the water appears to drain to the entry elevation. ( Front )
The only permanent fix is to seal the top so water can NOT enter all water must run off the top edge. A water proofer or Sealed will not keep all water out.
Keep in mine what is required for efflorescence. water - a path for water to travel & Calcium & salts if you eliminate any of the three you will stop the process.
Question in the photo page # 2 the mortar joint in this photo is that sand along the joint or is it hard mortar? Looks like sand is washing out of the stone joint above.


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## Tommysupra13 (Aug 21, 2017)

At this point I?m not sure what you are seeing in the picture could be send could be a mixture of both I have no idea, this job was done months ago and the contractor was supposed to come back and fix it but he keeps postponing it, he said he used regular thin set behind the cultured stone The project was planned, the electric snow melted wire was supposed to sit in the sand that way it would be closer to the pavers surface, but for some reason last minute the contract I thought it would be a good idea to mix in dry cement to help embed the wire and give the pavers a stronger base. There was no plan for a drainage system, the top level is pitched away from the house for the water to run off, the problem is when it was first done the cracks between the pavers were never 100% filled with sand, he was supposed to come back and fill it all but never did, so as it rained water got into the cracks I?m assuming and I?m also assuming this is what caused the white streaking on the cultured stone, my contractor doesn?t agree with me that?s why I figured I would ask on here for a more Knowledgeable opinion, which you have graciously provided. Knowledgeable opinion, which you have graciously provided What would you do next? Do you think I should try to fill up the cracks with sand and see if that stops the white streaking? Or should I tell him he needs to remove all of the pavers and attempt to remove the sand base without damaging the snow melted wires?


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## ClarenceBauer (Mar 4, 2005)

The following is my opinion:
Clean a small area using Vinegar and wash with water than see if the amount of efflorescence decreases in that area if it does let the natural occurrence take place. From the photos it is my guess that there is about 8 to 10 inches of a calcium product making up the patio surface. with this thickness you could estimate that all the Calcium will vacate the area in about 18 / 24 months.
The free lime that has migrated to the face of the pavers will mostly remain as it is locked in the pores of the pavers.


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## Tommysupra13 (Aug 21, 2017)

So I started this post about a year and a half ago about a new porch I had installed with cultured stone and the mortar was bleeding white residue onto the face of the stone. About late November the contractor finally came back and ripped off the stone and replaced it. Now it’s 4 months later and it is slowly happening again!!! I can’t believe it. At first we all had the suspicion that it was because he used a dry pack and sand mix under the pavers on top and it was leaking through. But when they ripped off the cultured stone it all looked sealed up and there were no drip marks. Why the hell is this happening !? Does anyone have any idea becaus I give up. Should I try and seal the stone before it keeps getting worse ? Any help will do. Thanks.


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## Tommysupra13 (Aug 21, 2017)

This is the new leak stain.....


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