he left it on too long, or it was too strong no matter how he claims otherwise.
Exactly that. My guy tried to blame the plaster, too, but it doesn't matter even if the plaster
was defective. There's a proper way to go about acid washing (or any application of acid to stone or plaster).
- First, a discussion should have occurred about the nature and consequences of acid washing. Without giving the consumer a chance to understand the potential risk and the inherent downside(s) of an acid wash, the provider is negligent. And that should have been in writing in addition to a discussion. Acid washing does not magically attack stains (or whatever needed treatment), and leave everything else alone. It dissolves the plaster and takes stains along with the removed plaster. So there is really no way to acid wash a pool and not end up with less pool. It's bad enough with a plaster finish, which will be left etched and feeling rough. But with a pebble finish, it's the plaster holding the pebbles, so if you remove plaster, you're going to weaken the bond of the pebbles!
- Secondly, the provider should ascertain if acid is even appropriate. Less aggressive remedies should be tried first, and acid use as a last resort. And only then with the understanding that it is a quick fix to maybe get an extra year or two out of the finish. It's maybe appropriate if the finish is already on its last legs. Never for a newish finish. Either way, it's going to shave some lifespan off the finish. Skipping that first step, IMO, is also negligent.
- If it is determined that acid is the only remedy, and the consumer has been educated about,
and has agreed to the risk, then the next step is to determine the "strength" of the acid required (paraphrasing, 'cause it's not really "strength"), and duration of application needed, to achieve the result, while at the same time making sure that the process will have no unintended damaging affects (there's going to be "damage" even if an acid wash is done perfectly). That's done by simply trying various applications in a small, out-of-the-way place.
That is acid application 101. Since no two pebble/plaster installs/ages/condition are the same, there can be no "blanket" formula for acid washing. It has to be determined case-by-case, and on the fly. That is probably the single most important skill to possess for someone selling acid washing. And should the plaster be defective in some way, such that it could not withstand an acid wash of
any method, that too would be revealed by this sampling step. Which is why he can't now claim that it was the plaster, because, as the "professional," he was responsible for determining what acid application to use, and if it was safe to use. If he took this step and did it wrong, or if he skipped it (of course he did!), either is equally bad, and equally his fault.
- and finally, the most important step of an acid wash is neutralizing the acid at the precise moment it is finished doing it's thing, so that the process halts and the acid can cause no further action (or damage). Most guys just hose it off into the deep end and pump it out from there, perhaps without doing any neutralizing at all. They think diluting acid with water halts the process. It does not.
So if he skipped even one of those steps (and I'm gonna guess he skipped them all), he was unqualified to do the work, and/or negligent in his performance.
Now where you might have some trouble, is in how long it has taken for the damage to reveal. Will you be able to prove that only the acid wash contributed to the damage you have been seeing? My situation was different, in that incredibly severe damage showed up the same day, and then it got worse each day after that. I had definitive proof that the damage was a direct result of the process.
I'm not a plaster or acid washing expert. But I learned a lot when my pool's plaster was destroyed by an acid wash. I called in experts. I researched. And I got some support from TFP (most of this occurred before I found TFP). I took lots of pictures. I saved chunks of the pool that were removed during the repair (I had it fixed before I "won" anything from the perpetrator). So I was ready for court. But when I presented all that when filing my complaint with the CA Board, that was the end of it. They took a long time, and they first said the contractor was not going to do anything. They suggested court. But then about a month later they called and said the contractor agreed to pay for the repair. I never did get to the bottom of why.
