Mastic vs. Thinset III

Mastic Vs. Thinset III

Looks I'm a little late on posting to this message board. I would have liked to get into the arguement back in May - but I figured I'd post anyway.

I hope that I can save at least one person the same headache that I have encountered!

I've invested $10,000 bucks in a bathroom remodel.

The Problem - Ceramic Tiled Shower Stall - there was MASTIC used on the shower walls (stand up shower stall type shower). Mastic was applied over 1/2" cement board - The instructions on the mastic pail (acrylpro) indicate's you can use it on SHOWER WALLS. My tile installer swore by this mastic stuff (I personally wanted to use thin set) - NOW I"M F*C*K*D! I'd like to mention that everything else in this application was done by the book, with only the best!

Well 4 months after the job the mastic is emulsifying behind the tile and the tile is coming loose on the shower walls. It appears the moisture is getting in through the grout lines and causing the mastic to breakdown.

This one says this, that one says that - the instructions tell you one thing, the ANSI says another thing - ALL I CAN SAY IS MASTIC SUCKS IN ANY WET APPLICATION! I LEARNED FIRST HAND, THE HARD WAY!

NOW WHAT AM I TO DO? I will have to rip the whole thing out and start over.

THESE PEOPLE USING MASTIC. I'd like to see how there work looks in 10,20, 30,40 or 50 years from now. When you look at tile jobs done in the height of the Art Deco Era 1930's - installed with thinset cement - the tile still looks good. Why change a good thing for the sake of ease? Which I venture to differ with.

I'm very angry about this, and rightfully so. I'd like to know how many people have had the same problem. I'd like to know why the instructions on the pail say that Mastic can be used in some wet applications - hence, a "shower wall". tub surrounds etc.

I say NO to mastic used in any wet application. I would argue this point no matter what.

I'm sorry you had to find out the hard way, But I'm glad you were willing to post this. I can't even COUNT the number of people who come in here and argue that mastic is fine for shower walls. Thank you very much.

Hi Bill,

Why can't anything be done about this then?

How long is this gonna be allowed to go on?

How much money is being wasted by unsuspecting people like me by simply following the manufacturer's directions while others are getting rich off of selling the product?

Unfortunately, If it meets certain criteria, they can claim its use for wet areas. Same for going over plywood. Then someone comes along and sees that, and well, if it says it's okay, then lets use this-- it's an easier product to work with! And then they end up in your shoes. Unfortunately this is just the tip of the iceberg, concerning misinformation and bogus claims in this business.

If a shower is tiled with mastic, and grouted and siliconed properly, and the silicone is kept up over time, then wouldn't the installation be just as good as a thinset installation? If water can't get in, then what does it matter whether thinset or mastic is used? In the case above, bigcap stated that water is getting in through the grout. That problem has caused the mastic to deteriorate. Wouldn't this all have been prevented if the grout was installed properly, and not allowing water through?

Sorry, Phil. Grout is not waterproof.

Bill - What can I do about it?
I can't just sit back and do nothing.

You say that there is certain criteria, guidelines - Don't understand why for instance Laticrete Mastic Type 1 - claims in their direction's for use "non-wet interior areas only. Do not use mastic in stand up shower stall walls, do not use mastic for shower floors". Yet you read Acrylpro Type 1 Mastic directions and they state - "exceptional durability in wet areas. Areas of use include- Interior wet areas w/ prolonged water exposure such as tub surrounds and shower walls. Do not use in steamrooms, shower floors, underwater or areas exposed to hydrostatic pressure".

With that said aren't all Type 1 Mastic's defined the same by ANSI A136. 1 Type 1 requirements?

What the heck is going on here? Please Help!

Phil- Grout is permeable to water and moisture no matter how well it's sealed. -- and also - MASTIC RE-EMULSIFYS when subjected to water-- SO WHY USE A PRODUCT THAT WILL EVENTUALLY DETERIORATE WHEN EXPOSED TO WATER OR MOISTURE?

THINSET DOES NOT DETERIORATE WHEN SUBJECTED TO WATER - IT SHOULD BE PLAIN AND SIMPLE.

Ahh but epoxy grout IS waterproof if applied properly and with no pinholes etc.!

And If you feel " IT SHOULD BE PLAIN AND SIMPLE ", I guess you should have plainly and simply made sure your installers were using thinset not mastic!

Sorry bigcap if I am not as intelligent as you fancy yourself as being.

Bigcap

Sorry to hear of your pain.

I never use mastic where any water is a issue.

As for your grount leaking. It dosent really matter

Mastic will still fail from condensation.

Simpley if u had the worlds best grout and no water could get in.

If you change the temperature of the front of the tile with say water.

The rear of what every surface will then get wet.

And since most mastic is water based now.
I never take the chance.

It will fail. Sooner or later

Yeppers

Phil - I didn't mean to come across harsh. Sorry if I offended you.

I trusted my installers expertise and advise. I also read the directions on the mastic container just to be sure it could be used in this application, and it said I could.

Epoxy grout- I'm not familiar with this - I will take your adise and look into it. I used laticrete grout (not sure if this is epoxy or not, I do believe it has a latex additive).

I'm not a expert by no means - far from it! - but I have been so upset by all this that I have researched long and hard. All I can do is pass on this info.

Again, sorry if I offended you.

Bigcap-- That's the difference-- Laticrete is a reputable company. But even that's not a guarantee. I know of a couple of reputable companies, as well, who say their mastic is fine for wet areas. Keep in mind, that normally, the only place where mastic is used wholesale for wet areas is in Big commercial construction, such as in hotels, apartment buildings, condos, etc.-- places like that, where the contractor doesn't give a damn about anything, so long as the building stays together for ONE YEAR. After that, it's very possibly a client for renovational work. In these circumstances, the mastic normally holds up just as long as it needs to. But not too much longer. Keep in mind, alot of these places are still using green board for their walls, too.

Oh, And Phil-- just for the record, in 24 years of setting tile, I've done ONE tub enclosure where epoxy grout was used.

Just a question, I am a tile setter and I was taught
That using a high quality mastic was "ok" to use in a shower stall. Up to this point I have never had a problem. No call backs or complaints. I learnt from my father who has been in the flooring buisness for 30 years. And yes I know that does not meen anything, He could have been doing it wrong for 30 years. He has never had any call backs or complaint either. Or any of the many guys that have worked for him. But even with that said there are a few things that I fount out were wrong that Ive learnt from him. Now that, I am out on my own. I just wont to do things the right way. But my major argument is if mastic remulsifies or whatever it is why does thinset come out off my cloths in the laundry and mastic does not
Im not trying to argue just want to protect my a$$.
In need of knowledge. I do hold a lot of pride in my work and the tile industry in general. Im a lifer.

What detergent are you using, I can't get the thinset off of my pants, just the heavy stuff breaks loose, same with mastic.

Anyway, yes, mastic can breakdown and turn to mush when exposed to water over a period of time, I repaired 2 shower floors alone this year that the former installer used mastic to set the floor tile, what a mess 6 months later, it takes longer on walls, needs a leak or bad spot in the caulking or grout to let moisture in, not worth taking a chance in my opinion, yes, I've seen them last years, but thinset is a gaurantee, that it won't fail due to moisture or water getting to it.

Also, why use mastic at all, the damn stuff is so expensive, mixing thinset takes only a few minutes and cost less to use.

Joe Tile-- One other thing to remember-- up till the early 80's, there WAS a mastic available that was solvent based, and didn't break down from exposure to water. However, it also has carcenogenic fumes that hung around long after the tile was installed, too. One way or the other, it was taken off the market. But that's why you see alot of older showers that were installed with mastic still standing.

I am not sure if I have thinset or mastic, all I know is that a 12 year old house is having its second shower pan replaced. This time the tile floor and walls close by will have to be replaced.

I don't know if I should blame the products or the people. I have never had such a problem that would not go away.

Leaks never show up within the "year" of warrantee.

The first guy can still claim he has not ever had any call backs, because he will not return my calls. Thats one way to protect your name. Lol.

Jane, a couple of things to keep in mind when takling to your installer. First, do not let him use greenboard. Make sure the installer is going to either use a moisture barrier behind the installation or is going to use a topical waterproofer on the substrate. Make sure he builds a preslope of mud under the pan liner and make sure he does not use mastic anywhere.

Well,

This has been very informative. I'm with bigcap on this issue. Somehow the industry needs to get it's act together and get the word out if infact modern mastics are really no good for shower walls.

I'm renovating an old house in Maryland and was going to tile my own tub surround but then due to time constraints decided to job this out. I've gotten several quotes ranging from $350 to close to $800 for a simple three wall alcove in 4 inch matt tile. The crazy thing is everyone I have asked has told me that they are using mastic exclusively for setting wall tiles in showers!?!

Everything I have always read on the subject suggests that thinset is the way to go, and this is what I had planned to use if I did the job myself. Now, I don't know what to do. I guess either I insist on thinset or (if noone will use it) I do the job myself.

What a pain in the a**! I'm constantly amazed by the lack of informed people working in the trades these days.

Clay

The tile industry neither condones or recommends mastic or greenboard in wet areas. In the US we have installation standards of which the manufacturing community is one of 4 segments represented. The Tile Council of America publishes (but does not set) the standards (www.tileusa.com).

The conventional shower stall built of either entirely of mortar or a combination of a mortar floor and backerboard is still the most popular method of construction. One of the most often emited steps to a long lasting installation is the pre-pitch of the waterproofing. One thing mortar readily does is absorb water. It is a common misconception that tile and grout make a surface waterproof. Grout will readily absorb and pass water through to the mortar shower base. This water should pass through small holes known as weep holes in the bottom. It will not pass if the membrane is lower than the holes in the drain. The water will instead collect and harbor all things carried with it. Given the proper circumstances this can lead to mortar degradation and mold, a very sensitive issue these days. Even with the pre-pitch, the weep holes need to be kept open. This works much like a drain tile, you need to have a space for the water to collect and pass through the holes. When this is not done and and the bottom of the shower wall is grouted or otherwise touching the floor, water migrates to the wall it wicks up and causes and causes the wall to be saturated. When mastic is used it will re-emulsify after some time to exposure. True professionals are well aware of this. As noted in the end of your post, it is the lack of education in some instances or just plan being lazy and not caring in others.

I have been reading this discussion with interest, as I just had a bathroom remodeled and my installer used mastic to install tiles for a tub surround. The tub is also used as a shower, so the tiles will get wet.

Is there anthing I can do to try to protect the tile/make it last as long as possible, or is this just a disaster waiting to happen? The tiles are 3x6 ceramic with very fine grout lines.

Molly there is little to be done at this point. You could seal the grout and keep it sealed but that won't prevent the inevitable.

The entire industry of building trades is undergoing an evolution of sorts. Unfortunately this evolution is lowering the bar-of-standards. Old fashioned craftsmanship will one day be non-existant and will have been traded for methods that today are faster than they were yesterday. This building industry of ours and all the developers and investors that participate in it are of the concept that faster is better. Faster is labor saving and faster is therefore dollar saving. Returns on investments come faster and are greater. Faster means more projects completed in a shorter given time period and therefore more potential profits.

The truth is, this thinking and greed is in fact fostering shortcuts, eliminating traditional steps, and ignoring critical paths. Buyers are more and more going straight to the bottom line and not considering the long-term consequences of the so-called savings.

Manufacturers in a zealous effort to gain more marketshare are developing products that in no way measure-up to traditional products. There is nothing wrong with progress, but progress at the cost of longevity and quality is a big mistake.

Today's manufacturers, builders (not craftsmen), developers, venture capitalists, just plain don't give a damn about tomorrow. "Damn the torpedoes, full speed ahead". They will soon be changing their tune when they begin to connect with some of those torpedoes they are now so willingly dismissing and when some of their own torpedoes change course and cross their paths again.

Hacks and butchers are being selected over true craftsmen to do todays work. Incompatance abounds. Shortcuts prevail. Honesty is non-existant. True tradesmen are a dieing breed.

That's my doomsday speech for this month. Sad but true I'm afraid.