Oh-Oh Got Troubles!

[NS'Creter]

Heeeere we go. I just got a phone call from someone telling me that a job we did last year is peeling like paint. I haven't seen it, haven't even heard from the customer...the caller was givin' me a "heads up" kinda call. Obviously, I didn't do any of the physical work but I was there for every second of the project. Nothing was done wrong and it has to be product failure. We used H&C. My wife just placed a call and left a message on the customer's voicemail. We want to deal with this and make it right. I intend to inspect it myself and also have our Sherwin Williams rep inspect it. Not hearing from the customer makes me nervous. They are aware of my condition...maybe they wanted to take the court route? They can't do that unless I refuse to fix it though...wierd huh? I wonder what caused this and I'm very nervous about the other projects that we used the same product on. I'll hafta go check them all personally.

[Lindy]

Since H C is topical, in lieu of reactive colorant, I would be willing to bet it is a case of excessive vapor pressure (more than 3 lbs per 1000 sq.ft.). Is this an indoor slab (with a moisture barrier under it) or an exterior slab (where moisture barriers are not typically used)?

The amount of air entrainment in the slab can make the situation worse (in relation to pathway for excessive vapor pressure), if exceeding acceptable limits ... could have been even due to long/extended periods of rain, complicated by perhaps number of freeze/thaw if it is an exterior surface.

Strongly suggest that you preform a rising moisture test at the time you do your detective/inspection work. Best would entail using a moisture meter (probe type), but there are other types of moisture meters, along with calcium chloride test kits ... if you need to learn more about how excessive vapor pressure/rising moisture can and does effect longevity/performance/bonding go to www.vaportest.com Keep in mind though even if the excessive vapor pressure does not exceed 3 lbs per 1000 sq.ft. when tested, doesn't mean that it didn't exceed it for a period of time long enough to have caused the problem (such as can easily be the case when there have been long periods of continuous rain that saturates the ground and wicks back under the cement or in from the sides/vertical edge of the slab ... after all concrete is nothing more than a hard/porous sponge).

Excessive rising vapor/moisture can also bring with it a high/aggressive PH factor that can also be a death sentence for coatings since it eats away at the the bond away (especially when it comes to any acrylic stains/dyes and/or acrylic based sealers which are much more susceptible to damage/delamination if surface the are applied over/bonded to have high/aggressive PH factor). Typically, in cases such as these, the acrylic stain/dye and sealer will come up/delaminate together.

I know this sounds dump, but touch you tongue to the back side of a piece that pealed up; does it have a salty taste; if so this would be another clue as to an excessive rising vapor/moisture problem (extreme efflorescence/mineral deposit build up being driven to the surface; thus, becoming a a bond breaker).

Could have been some sort of invisible penetrating sealer or impregnature used on the slab at some time; that due to pressure was driven to the surface, bringing about this delamination issue ... only the property owner or contractor that poured the slab would have any insight into this (no way for you to have known).

Guess you will have to go play Dick Tracey ... if I can help out in sort of a Nancy Drew sort of way, shedding more light on the subject after you get a chance to inspect it, let me know.

Lindy A.

[Lindy]

Forgot to tell you along with touching you tongue to the bottom of piece that is pealing up to see if there is a salty taste ...also, dampen the concrete, not to the point of water standing, testing the concrete substrate beneath the pealing/delaminating material for its PH factor; again I refer you to www.vaportest.com to acquire if you don't already have one either a PH pencil for testing or PH testing strips ... there will be a color scale with both of these (PH testing pencil/instrument is best) with a corresponding number under each color ... anything reading 8 or higher is deemed excessive, the higher the number the worse the case is. If there was a excessive, more than 3 lbs per 1000 sq.ft. of vapor pressure at any time since you initially applied the materials used this will provide evidence of this due to minerals/salts being propelled to the surface bringing about the degradation/loss of bond (as stated about, if there were prolonged periods of rain, extreme ground saturation, that wicked under/into slab, in which case the path to evaporation would be up through the slab, coming in contact with your decorative coating/sealer, blasting it off, leaving the surface with a high PH factor).

Concrete also has a very high alkali content that remains within the slab upon cure out; in cases of high vapor pressure, again which could have come into play at any time after you applied the decorative surface (be it 1 month or 1 year down the road), this pressure will drive more aggressive alkali to the surface, which brings about alkali degrading/loss of bond issues.

Lindy A.

[NS'Creter]

Well there's lotsa stuff to work with! Thanx!
This 'crete is actually stuff that we placed and then did the pretty a year later. Even when I place outdoors I use a vapor barrier, but last year was a very, very wet year. Perhaps we have found our culprit? We will test for all possible factors which may have caused the failure and I have asked our Sherwin Williams rep to participate.
This was a very color specific project (of significant size) and that's why we used the H&C. It is the most readily available product for that purpose here. It will be interesting to get the suggested remedy from SW.

[aynet]

Wow, Trev - sorry to hear that. It is such a sick feeling when you've done a job and it has problems. I hate that!
This explanation of rising water vapor, however, doesn't make sense to me. I know you're the expert, Lindy, but if water vapor was the culprit, nothing I ever do would stick. Let's face it, if I do a vapor test, I'd never decorate a piece of concrete anywhere in south Louisiana. No exterior slabs have vapor barriers unless the client insists on it and the ground is so wet that vapor seeps in from the sides any way.
I've used acid stains, water-based stains and H&C. All have done well. It's the interiors that cause us problems. That's why the rising water vapor just doesn't seem like enough to do this. Could the difference be climate - as in temperatures (freeze/thaw) etc.? Or, could it be something used on the surface for de-icing or snow removal?
Since we have LOTS of water in the ground and we've had really good success with H&C here, I'm looking for another factor that could cause the problem. You could be spot-on for this, Lindy - just wondering if there might be another culprit for the sealer/stain letting loose.

[Lindy]

I didn't catch it was an exterior ... I thought it was interior, whereas there would (or should be) a vapor barrier (if not, it the problem could be a excessive vapor transmission problem in random areas if/where the moisture barrier was compromised). If there is an exterior slab, moisture barriers are definitely not the norm.

Do ya'll have ASR (Alkali Silica Reaction) issues with your concrete slabs in Canada? You might want to google and read about this.

There is a difference between moisture contained in all concrete (more so in some parts of the country than others) and excessive Vapor Transmission issues ... coating bond failures are frequently cased by excessive vapor transmission (again, not simply moisture that has wicked into the slab from below). Anyone (such as our friend Aynet) in parts of the country like Louisiana (high water tables) have had to work through a wide range of moisture content in slab issues, compounded by random cases where excessive Vapor Transition has taken place that not only creates a pressure valve but can also drives bond breaking elements to the surface.

If it was an exterior surface, contaminates left from deicing materials could have caused concrete at the surface of slab to become weak. What do the back side of the pealing/delaminated pieces (stain & sealer) that are lifting off look like (residues on the back/under side of them) ... are do they have a whitish cast, taste salty, does the concrete have a darker than normal/damp appearance under them, etc.?

Lindy A.

[aynet]

I want to understand what you're saying, Lindy.
Do you mean that a constancy of moisture isn't the problem, but certain pockets of water pressure that cause the problem. Is this why we can do decorative surfaces, even outside somewhere like south Louisiana and not have failures?
I'm just trying to gain an understanding as to why we make it work when I hear all this stuff about moisture levels and vapor transmission and etc. etc. that don't work here. The only issues we ever have is surface issues like exterior force damage or poor concrete finishes that slough off.
Can you explain further so I can GET this? Cause I'm kinda dense about this issue I guess.

[NS'Creter]

I still haven't gotten to actually see this one yet. The customer's schedule didn't allow for it, I'm not very mobile, my Dad is getting remarried today and I want the SW rep with me as well. The type of people that the homeowners are I have no doubt that they've had every concrete contractor who would come take a look at it. They would do that before calling me and have probably also spoken with their lawyer too...all before speaking with me. I don't like that. I have heard of one contractor being contacted but he refused to go. I should add that no other person does what we do...the guy would refused does drilling and coring. Anyway, we'll go to investigate and hopefully determine what happened and why...then repair the problem.

Most contractors here don't utilize vapor barriers for exterior placements either, but I do. I also do overkill with the gravel substrate and reinforcements and actual slab thickness. I want my work to last a long, long time. And when something goes wrong such as this I fix it. Can't be any other way. ;D

[Lindy]

I'll try to explain a little further...

Non-breathable resins/coating/sealers are all susceptible to bond failures if/when there is a Moisture Vapor Emission Rate (MVER) greater than 3 lbs per 100 sq.ft. The higher the MVER, the higher the level of alkali being transported to the surface mils of the concrete substrate; thus, the term alkali degradation (bringing about the breakdown of interface bond).

All concrete, old or new, contains water necessary for batching, along with "free water" that is left in the slab (not consumed in process of cement hydration; therefore, "free water" is left in the concrete as non chemically bonded water. Time and drying conditions will reduce the amount of "free water" but will not eliminate it.

An "open slab" has no below slab vapor retarder; therefore, not only will "free water" be a concern, but also water vapor rising from below that will cause moisture levels in concrete to rise if/when impervious sealer/coatings are applied.

Excess MVER also creates a pathway for aggressive soluble alkali (having a high PH factor) that can bring about loss of bond at concrete and coating/sealer interface.

If you get a chance you might want to read the following article...
http://itwresintech/pdf/library/mea_rem.pdf which is a very well written/informative article by industry professional.

Lindy A.

[Lindy]

Oops "typo" above ... MVER rate should read no more than 3 lbs per 1000 sq.ft. (not as per my typo 100 sq.ft).

Lindy A.

[aynet]

That does help, Lindy. Thanks.

[Lindy]

You know what really get me, is that everyone slings around the term "Act of God" so freely (not just in our industry, but in other non-related ones as well). It is sort of a catch all reason/excuse used to cover any/all issues that may have been beyond foresight to predict. This "Act of God" phrase has become a "legal term" over the years ... which equates to "it's no one's fault" (contractor, materials applied, concrete substrate itself, etc.), but in reality everyone looses (1) property owner invested in something that started out a beautiful/creative work of concrete art; however, some sort of unforeseeable problem comes to life over time due to "Acts of God," unless contractor has a crystal ball to see into the future; (2) contractor gets blamed for the issue, which can damage his/her reputation and land him/her in court trying to defend themselves against some unpredictable "Act of God" predicament; (3) material supplier gets brought into the concern/problem, claiming "Act of God" if/when there is no other explanation for the issue (such as excess/random MVER, loss of bond, cracks in overlayments due to stress on substrate, etc.).

I don't know what else unforeseeable, undetectable an/or invisible (lurking in the slab), problems brought about by non-typical/randomly occurring reasons could be referred to other than "Act of God" but I simply don't like that term since I don't believe that God should be blamed for any of these issues either. Maybe a good legal term to replace it would be "Act of Murphy," since everyone is quite familuar with the term "Murphy's Law" (what can go wrong will go wrong) ... I don't know who this fabled "Murphy" person ws, but I am glad I have never walked in his shoes long enough over time to have a common phrase named after me!

Lindy

[NS'Creter]

;D Excellent point of view! Good idea on the renaming too, I like it. ;D

[Lindy]

Guess we have solved 2 "renaming" issues ...
(1) you have CRaPS; not CRPS
(2) unforseeable/non-predictible problems are from this time forward to be referred to as "Act of Murphy" instead of "Act of God."
There are some other odd phrases as well like... I'll be "out of pocket for a while"... what is that supposed to mean, sounds like a phrase that only a politian would use.
The term the "grass is always greener on the other side of the fence" makes sense ... you always see cows and horses sticking their head through a fence to eat, no matter how much grass there is on the inside of the fence.
A common term in the southern part of the States (my neck of the woods) is "that dog don't hunt," meaning that whatever is being said will not take place (is b.s); I kind of like this phrase.

Lindy

[NS'Creter]

Finally have an update for this topic as well. The SW rep and I went and inspected both of the call-back jobs. Definately a moisture issue...no question about it. Looks like the seal got penetrated somehow, water got under and did it's thing. On one of the jobs it's very evident where some scraping was done and that's what most likely caused the failure there. It just so happens that they have been the "pain" type of client all along. The other is a "gem" of a client. It doesn't matter, I want all of them to be happy with their experience and although the future of my biz is uncertain my reputation means a lot to me. SW is going to supply the product and I'll see that the repairs get done. I'll hafta reeducate them on the maintenance and care of their 'crete. I think that I'll put an extra coat of clear on both as well. I always do 2 of color and 2 of clear as a minimum but a third should help huh?