wire mesh [Archive] - Ceramic Tile Advice Forums - John Bridge Ceramic Tile


View Full Version : wire mesh

05-20-2001, 09:12 PM
Hi John
I have a few questions here that I shouldn't have to ask(since I should already know the answers), but I have 600sq ft of the ugliest tile you have ever seen, that needs to be removed. Unfortunatly is is installed directly on the plywood subfloor(5/8th) which has been covered with wire mesh( i'd like to know who came up with this idea..it seems to be everywhere up here)..and after 9 years..not a crack anywhere(go figure). My question? If I remove the tile, and the mesh stays fixed to the subfloor, what's the minimum thickness of a mud floor I can apply? I'd like to avoid 1/2 inch backer board if it's possible, but I need the strongest floor I can get for the slate that is going on top. And yes I've thought of Ditra matting..but it cost more than the slate!

I'd like to know who did the tile...beautiful job..Harry was it you? It's in your neck of the woods.


Sponsored Links

Rob Z
05-21-2001, 06:15 AM
Hi Bri

I buy DITRA by the roll for economy pricing, and pay a little over $1/sq ft. Off the roll at the supply house is more expensive, but still less than $2/sq ft.

The thinset over lath method you describe has been used for a long time. It's condemned by the TCA because it has failed in the various tests that they have performed on test panels. One time I toured the TCA testing lab and saw the results of just such a test.

You probably won't be able to reuse the lath, since it is (likely) filled with thinset. That's the theory behind this method-the lath reinforces the thinset to form a mini-mortar bed.

For mud on floors, I like to go with a minimum of 1 1/4 inches. On small floors, that can be reduced a bit.

Let's see what John has to say....

Rob Z

John Bridge
05-21-2001, 06:40 AM
John has to head out to the job, be he'll be back this afternoon.

05-21-2001, 03:10 PM
Hi Rob
I also think it is a crazy way to install tile...I've turned down many a job,because the home owner insisted they wanted wire mesh method..I've also been called to many a home that needed repair from this installation method...but people still want it. Anyway, it's going to be a nasty one to remove..and it's too bad..because the setter did a beautiful job...near perfect. Too bad the tile is so ugly. Green with a repeating pattern that looks like a giant chicken walked accross the floor with green paint on its feet. It wouldn't look so bad if the setter had flipped the tile around,so that chicken feet didn't run in all the same direction..but anyway...I always put at least 2 inches(mortar) on wood substrate..I worry about any less...and since that isn't an option, then the Ditra is probable the way to go, since there will be a lot of thinset stuck to the floor after the mesh is ripped up. I'll probably have to level it up a bit first with thinset again...Geez! How do I get these jobs!!!

Tile Setter Rule Number One:

Never say "yes" when a family member asks "Could you do a little tile for me"

John Bridge
05-21-2001, 05:20 PM
Hi Boys,

Until recently I thought the only place they did things that way was in Florida, but the practice seems wide-spread now. I don't think the wire mesh (lath) does a thing in this case. That the installation has held up is probably due to the strength of the subfloor -- must be a good one.

The minimum thickness for a reinforced mud substrate (lath and mortar) is 3/4 in., and that can skim down to 5/8 in. in isolated spots, because in other isolated spots you'll have an inch. Even my friend Michael Byrne will agree with me on this -- he has stated as much on his own board.

I like an inch. Putting 2 inches is a lot. We do that only when the house has been built for it, i.e., depressed floors.

As far as the giant chicken feet are concerned, maybe the setter thought they were unique and beautiful. "Beauty is in the eye . . ."

What to do? I don't know, buddy. I'm glad it's you and not me. But I've been there. I try to back away. Sometimes you can't, though.

600 sq. ft.? Two pick-up truck loads to the sanitary fill. Yeah, I'd tear it out and start over.

05-21-2001, 06:18 PM
Oh well...at least the fishing is good up there....

thanks everyone!


John Bridge
05-21-2001, 06:25 PM
Hey Rob,

I forgot to mention that paying around a buck a foot for the Ditra seems like a pretty good deal. I buy my fabric-type membrane for about that. Of course, I don't buy in quantities.

05-22-2001, 09:09 AM
If your elevations will permit, you could simply leave everything as is and cover with a 1/4" of self leveling cement. Just make sure the existing tile is absolutely clean and follow mfrs instructions.

05-22-2001, 11:33 AM
That would be an option if the original floor was the proper thickness, but since it's only 5/8 I'm afraid the tile is going to have to go...right down to the plywood. After that, I'll probably put 1/2 hardiboard or similar..or maybe Ditra...I was just hoping someone had a new product I hadn't heard about.


05-22-2001, 12:46 PM
Oh well we tried, hate to see all that effort- Hey! how about dumping 3" of new concrete? JUST KIDDING-JUST KIDDING DON'T SHOOT!

Bud Cline
05-22-2001, 03:18 PM
WOW Jim,

Your really stickin' your neck out with that one. Haven't you seen the trouble I've gotten myself into lately?

John Bridge
05-22-2001, 04:18 PM
You don't have to worry about getting into trouble around here, Bud. Unless you advocate putting tile over sheetrock in a shower area, that is.

As far as cutting up is concerned, don't worry about it. Life is too short.

05-22-2001, 04:31 PM
"You don't have to worry about getting into trouble around here, Bud. Unless you advocate putting tile over sheetrock in a shower area, that is.".......with Mastic!


John Bridge
05-22-2001, 04:46 PM

Bud Cline
05-22-2001, 06:10 PM
Hey now that YOU'VE mentioned that, (tile over sheetrock) do they still do that a lot in Texas? I can remember most tub/shower jobs I did there were always setup before I got there, and always on sheetrock. Most times it was greenboard, but by George not always.

I no longer do things relating to tile that I don't want to do. I've had some retailers around here pissed because I refuse to hack a job for them. It took a while but now they have learned when to call me and when not to.

Just curious!

John Bridge
05-23-2001, 06:36 AM
Yeah, it goes on. A few of the tract builders are switching to cement backer board, but not many. Latney is over near San Antonio, and apparently there's a lot of it there, too.


05-23-2001, 07:37 PM
Hi Folks!

Up in the Ontario area, places like Home Depot and various builders are opting to use "mesh / scratchcoat" .... I guess because it's cheaper (at least from the builder's perspective) for the material compared to plywood or cbu.

I could offer to install cement board for people for the same price as the mesh, but in most cases they would still go with the mesh and that is because they believe the mechanics to be the same as with the "mortar bed" method and therefore superior.

My worry is that many of the home owners who have problems with their tile flooring 4 or 5 years down the road because of an improper substrate, will have a negative influence on future buyers.


05-23-2001, 08:40 PM
Hi Harry
I was wondering about the substrate issue....is mesh/scratchcoat a good choice if you have 1 1/4 substrate below it?...I always seem to find it on 5/8 subfloor..whoch of course isn't enough(in most opinions). By the way, the job in question is just down the road from you. I should have stopped in to say hello...


05-23-2001, 11:58 PM
Hi Bri
Stop by anytime ... just look for the guy with a chainsaw in one hand and a Molson in the other. I've been getting rid of some of the unhealthy trees on my property the last couple of weekends. Or my wife out playing with her 3 new baby ducks. I named them Easter, Christmas and Thanks Giving ..... but she sees no humour in it.

I guess the thing with scratchcoat, is that it doesn't bond to anything, but just sets embedded in the mesh as a barrier between the existing floor and the tiles. It easily crumbles into a gravel when banged or stomped with your boots. But if the floor is already 1 1/4" thick, at least you don't have to worry about the strength factor ... or lack of.

I know that there are guys out there who use "scratch" all the time with their builder jobs, but rarely do it with residential or any other private contracts and these are guys that do great work, but they need the filler jobs (builders)to keep their helpers going. I guess it all boils down to the ability to cut material costs.

I was in a house the other day looking at beautiful and very expensive 17" marble tile installed over a scratchcoat on top of a 3/4" particle board floor. The whole entrance, mud room, kitchen, halls and powder room all marble. The guy bought the marble from Home Depot and I can only speculate that the directions or professional advise came from them as well. With these heavy hitters telling the consumer that mesh/scratch is OK .... who are we to argue.
I'd be curious to know if Home Depot promotes the stuff in the USA for floors as they do here in this part of Canada.

OK .... I'm starting to ramble.

Take care ... Harry

John Bridge
05-24-2001, 04:22 PM
Don't worry about rambling, Harry. Tell me what you think about the Slibowitz?


05-24-2001, 06:30 PM
Hi Harry
I spoke to a couple of guys from Hamilton, working down this way, and they use scratch coat on every job. I asked them about bond failure and they said they always use the best thinset they can get(top of the line) and when they do it never fails. He said the guys that use cheap thin set are the ones causing all the problem(I still disagree though). I just heard today, that there is a crew in town from the Toronto area, who are puting down mesh/scratch coat, suppling the tile and the labour...for $3.00...that's $3.00 Canadian ! I may have to move to Texas!!!!!


John Bridge
05-24-2001, 06:36 PM
C'mon down, Bri. I can't get up in the morning for $3 Canadian. It's hard to rouse myself for $3 American! Of course, it's getting harder and harder to rouse myself, period.

John Bridge
05-24-2001, 07:16 PM
On another note, though. I wonder how long these guys from Hamilton have been in the business. It's fairly certain their method hasn't withstood the test of time.

I think Dave Gobis is still screwing off down in New Orleans (Coverings). We really need someone here who can speak with authority. Where are you, Dave?

[Edited by Admin on 05-24-2001 at 09:19 PM]

05-26-2001, 07:41 AM
It sounds like the 5/8" is the big problem, otherwise you could tile over tile with a multi purpose thin set or have you heard of medium bed mortars?

You didn't mention the size of the slate, medium bed mortars are reccomended for all marbles and tile 13" x 13" or larger. 1/2" x 1/2" notched trowels or larger, and prevent most of your back buttering.

Why is every one paying $1.00 or more for ditra when you can pay at least 1/3 less for cement backer board and if you buy one whose reccomendation is the same as the TCA's
you can use dry set mortar under it for a leveling coat and save another 4 to 10 cents a square foot.

Unless waterproffing is an issue, use 1/2" cement backer board. Cement has worked with cement pretty well for ages.

05-26-2001, 07:57 AM
Yeah..I'd like to use concrete board..or similar..but until I rip up the existing, I won't know how much material is stuck to the subfloor, and height will be a problem. I realize even with Ditra, that I need more than 5/8 to put 12x12 slate...but I guess I'll cross that bridge(not you John) when I get to it.


05-26-2001, 08:16 AM
As you will see in the next new thread, I'm new to this forum and didn't go to the second page and see that the conversation had turned to wire lath and thin set.

I saw alot of this in Cleveland, and wire lath and self leveler in Buffalo. They swear by it.

They are really just making there own cement board. At least they are getting off the OSB that is so commonly used in that part of the country by the builders.

06-02-2001, 08:49 AM
Hey John and everyone

I'm off to the wire lathe green chicken feet job...I'll take the digital camera and send pictures.