I hired a “reputable” tile setter to install tile, in tub- shower surround. I never asked the question: What do you use to set tile?
He showed up Last Monday AM and I then left the house for an hour. When I got back he had already set most of the tile on the long side wall up to the ceiling. I noticed his setting material was white and appeared to be premixed. So I had to ask the question: What is that stuff you are using? Answer: mastic
Oh no, you’ve got to be kidding me! Response: I’ve been using this stuff for 10 years, never had a problem. My response: Good for you, but your not using that stuff on my shower, take it all down!
Now I have a CBU wall with a light skim coat of Acrlaypro mastic. This has been on there for the past 7 days. Question: How clean does that CBU need to be for proper adhesion using a Versabond type thinset? I just tried using some hot water and soap to see if its easy to remove and so far it looks like it could be a bear of a project to get this wall back to its original form. Please help before I waste time I don’t have. Thanks.
Replies
Please help before I waste time I don't have. Thanks.
If you are truly interested in saving time, and in getting that mastic out of the house, then take down those two sheets of backerboard. Just hang some new backer, and then start over.
That would be a LOT faster that any method of trying to disolve/remove the stuff. And it would assure a smooth intact surface.
Unless you're the lead dog, the view just never changes.
YesMaam you are correct, taking down two sheets of CBU would be easy. However in my case I will need to take down every CBU sheet. The CBU sheets in question (long wall) where put up first. The two short walls followed thereby locking the long wall sheets in at both corners.
If I have to take everything down I will, but I'm really wondering if the CBU as is OK or need to be cleaned for proper thinset adhesion.
Thanks everyone for your comments.
"taking down two sheets of CBU would be easy. However in my case I will need to take down every CBU sheet. The CBU sheets in question (long wall) where put up first. The two short walls followed thereby locking the long wall sheets in at both corners."
Cut them down the middle and slip the two pieces out, then replace the same way with the joint on a stud.
Breathe deep...relax.....this problem too shall pass......
Bob
If I have to take everything down I will, but I'm really wondering if the CBU as is OK or need to be cleaned for proper thinset adhesion.
If it is your opinion that the mastic is a bad thing, then it should be your opinion that it is bad both to hold tile, and as a substrate for mortar. I mean, either the stuff is bad, or it isn't.
And if it is, then the only way to get rid of it is to excise the backer board that has the stuff on it.
As another poster mentioned, cut the pieces down the middle to remove them. And cut the replacements so that the joint falls on the center of a stud. Presto-chango, the job's done.
And for what it's worth, I could have done that four or five times between when I wrote my first reply, and now. Including the trip to the yard for more backer. And a second trip to get some new sawzall blades. And another trip to get an extra piece of backer since I might mess up the cut.
Like the sneaker salesman said, just do it.
Unless you're the lead dog, the view just never changes.
I agree, just take the backer board down, and start fresh.
BTW, mastic on wall tile is not the end of the world.
"mastic on wall tile is not the end of the world."Yes, but the wall in question is the long wall of a tub/shower surround...see the first sentence of the thread.Rich BeckmanAnother day, another tool.
Missed it.
"Missed it."I'm missed plenty myself. It's easy to do!Rich BeckmanAnother day, another tool.
turn the backer board over?
I've used plenty mastic to put up tile without a problem.
If this was a real issue for you, why didn't you tell the installer in advance?
Try paint remover/spirits as a cleaner. Chances are it's easier to split the sheet and reinstall.
Don K.
I don't know how to say this without it sounding sarcastic and I really don't mean it sarcastically. But, anyway, here goes...
If mastic is so hard to remove with water, why is it such a terrible choice for a shower area? I recognize that there's a difference between keeping it wet for a few days versus staying wet for months, but how wet could it really get when it's protected by tiles and (presumeably) grout sealer.
I installed my own shower with mastic. I sealed the grout soon after it was installed, but not since. We've been taking at least 2 showers per day for the last 12 years. So far, so good.
I hope this isn't like the "Tyvek deteriorates under cedar shakes" discussion.
-Don
He knows he doesn't want to use mastic. Thinset doesn't cost much more and it's the right way to do it.
Billy
edited to remove my initial sarcastic comments...
Edited 9/26/2005 7:46 pm ET by Billy
Lets not turn this thread sour---
Mastic is definately not recommended in showers (or any wet walls) Mostly because water does get through tiles and grout (even when sealed) and over time, mastic typically degrades and lets go. I'm not saying it hasn't worked ever, but the point is longevity.
A good thinset tile job should last at least 40-50 years if well taken care of-----possibly more. You should also use some type of water proofer on shower walls (trowel on) that are being tiled.
In response to the original question, I would think you could turn the backerboard over no problem, if removed carefully? I don't understand why you would need to cut the sheets in half--?--- Take out the sheets in the middle of the wall first, and then take the screws out of the corner sheet and slide it out from under the other.
Shurely there wouldn't be screws within 1/2 inch of the end?
Just my 2 cents
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Si enchaupes mayolica, debes hacerlo bien
I decided to do an experiment:
I used mastic to glue a few pieces of tile together. Waited a week to make sure the mastic was fully cured. Then, dropped the tiles in a bucket of water to see how long it would take before they came undone.
I started this experiment Oct 1. figuring it would be easier to remember how long it took as the days/weeks rolled by. No such waiting needed. Later that same day, I could easily pull apart the tiles by hand. The next day, they were falling apart.
That settles it for me. Mastic is crap and not meant for areas that could see water. BTW, this particular stuff was AcrylPro ceramic tile adhesive.
-Don
Ok I don't think that post was meant for me. If you read my post, I never recomended mastic for this very reason, and actually said that it was inferior.
Plus, aren't you contradicting what you posted earlier? Does this experiment mean that you are going to tear out and redo your shower? You said in your post that you had taken 2 showers a day for 12 years, and I think you were advocating for mastic?
When in doubt, get a bigger hammer!
Right. That post wasn't specifically meant for you. It was meant to support the position that you and others were taking regarding disdain for mastic.
Does it contradict what I said earlier? Well, if changing ones opinion is a contradiction, then yes. But at least I'm willing to learn.
I will not be redoing my shower (at least not until it fails). Apparently, mastic can work under certain circumstances, but I'm no longer willing to take a chance that any new showers that I install will last as long as my current shower.
-Don
Glad you came to see the light!
thinset is much better, and cheaper too
When in doubt, get a bigger hammer!
I'm with the guys who say to use mortar over mastic! That said, sounds like you are using Custom Building Products Acrylpro mastic which if you read the instructions can (not should) be used in showers. But I would reason this; if you are going to go thru the steps of a CBU wall, then you might as well use mortar. However, now that it is up with mastic, are you going to ask the tiler to compensate or correct? How could they have known you didn't want mastic? These things should have been ironed out previously in the contract.... What I would offer to solve this would be you eat the cost of the CBU and removal, and the installer starts again the way you want it.
I called Custom Building products directly and asked the question. They say a light skim coat of mastic on the CBU will not affect the use of Versabond thinset ontop.
Problem solved.
However, now that it is up with mastic, are you going to ask the tiler to compensate or correct? -- I asked him to remove all tiles...he did. He said he wants to be paid for his time for installing and removing tiles...$300. I told him to send me a bill but before I pay him I would have to determine how much time I spent cleaning the backs of tiles, and as discussed here, the CBU. Cleaning mastic off 70+ tiles over 2-3 days...what do you think I'm gonna do?...one week later no bill has arrived.
How could they have known you didn't want mastic? These things should have been ironed out previously in the contract.... What I wanted was a professional job, not a quick and easy way for him to get done. This tile guy had the same response "You didn't ask for thinset" He agreed thinset was the better product to use in a shower but mastic was acceptable in his opinion. "If mastic is inferior to thinset, why would you use it" I asked him. "Because everyone including my uncle (old timer) uses it" Not a good answer in my book! What gets me is that the average dumb homeowner doesn't know thinset or mastic from a hole in the ground. That's why we hire so called "professional's".
I just hired myself for the tile work. I'm gonna pay myself $1,100, just like I was gonna pay this professional.
Good for you. I agree with what you've done and hope it will be avoided in the future.
Do you have room for a 1/4" layer over the top?
Next job, put up drywall and silicone and hard seam solid surface panels over a solid surface shower pan. No waterproofing, no mastic, no grout, no callbacks, no mildew ever.