What’s up?
Am tileing a small master bath with 12×12 marble tiles. Already replaced the existing sub with new 3/4 ply glued and screwed etc. I was thinking about using wire lath. In the past I’d just staple the wire lath to the plywood. Then I heard to put down tar paper, then the lath. I know I could use durock but I don’t want to build the floor up another 1/2″. Plus it seems kinda homeownerish. I will use durock for the whirlpool deck though. Any suggestions? Thanks-Pete
These personalized workspaces were designed to fit the unique needs and projects of their makers.
"I have learned so much thanks to the searchable articles on the FHB website. I can confidently say that I expect to be a life-long subscriber." - M.K.
Dig into cutting-edge approaches and decades of proven solutions with total access to our experts and tradespeople.
Start Free Trial NowGet instant access to the latest developments in green building, research, and reports from the field.
Start Free Trial Now
Replies
Hey Hammer
I would use tarpaper under the lath...it helps break the bond from the mud base and keeps it from future cracking as the ply expands or contracts. You are going to need at least 3/8 or 1/2 of cement to make a subststrate with the lath, why not use durock? Remember it is called THIN-set, and should'nt be used alone in the lath to attach the tiles.
I think your right nuvue. 3/4 " ply isn't enough to sup[port the marble. 1 1/8 min is better. Looks like I'll be using the 1/2" durock. Guess I thought it was cheating. Like a DIY product. I've done mud pans for showers, but laying a full mud floor and getting it level would be challanging for a first timer-Pete
I did it much the same way in our upstairs bath. Just used the top of the wire as a reference for level. Turned out great, and I've not got a very steady hand.
So convenient a thing it is to be a reasonable Creature, since it enables one to find or make a Reason for everything one has a mind to do. --Benjamin Franklin
I second/third the use of Schluter Ditra. Very cool product. Also acts as a waterproof membrane if you use Kerdi on the seams (another Schluter product, not necessary). In my book it means a lot that its from Germany and has been in use for 20+ years. I like it because its easy to handle, provides and very stable base, and is a lot cleaner than CBU.I'd add another 1/2 or more to meet the 1" min., depending on you joist spacing and longest span. As someone else mentione use the Deflectolator from the Bridge forum.Kevin
1/4" dens-shiled (made by georgia pacific) is a lot easier to install than cement board and wont make the floor too thick.
Thanks for the advice seajai. Ive used denshield before and it is easy to work with. I didn't realize it comes in 1/4"
What color is the marble?
Jeff
A number of people in past posts have recommended a membrane called Ditra to isolate the tile and provide a water barrier. The stuff ain't free but people think it is worthwhile. The website has an installation manual:
http://www.schluter.com/english/products/2002/pdf/ditra_handbook.pdf
Several places on the Internet sell it cut to size or in various lengths.
Ditra is great stuff and durock works okay... but, for added stiffness with minimal thickness, you cannot beat 1/4" Hardibacker! Personally I feel that 1/4" Hardibacker is superior to 3/8" Durock in EVERY way. The Ditra adds depth but has no stiffness gain. It is most useful to isolate cracked or jointed substrate from the tile bed so that defects don't telegraph to the surface.
Pete,
A subfloor of one and one eighth is the minimum thickness for any long lasting tile/stone job.
If you want to do it right and you want it to last then you just have to deal with the added height. My customers always complain at first about adding height like that but when all is said and done the issue is long forgotten.
As far as the lathe goes, that's really reserved now for an old fashioned "mud job" in which you might need to slope the floor for some reason (check out the latest article in FHB #185)
Also, I see no reason/advantage of using the Durock under the Whirlpool tub. I would mix up a bucket of cheap thin set and dump it on your new subfloor just prior to installing the Whirlpool tub. Then stay out of it for at least a day so it hardens.
So Pete ... what color is the marble tile?
Jeff
Jeff,
The marble is predominatly white with some black and grey veins. 12X12 X1/2" I was going to set the marble in regular thinset. I believe it has a honed finish
Sounds nice - I was curious since the darker marbles (red, green, black) are subject to curling and should be set in epoxy. White is fine though -
Jeff
The place where the tile folks hang out is
http://www.johnbridge.com
The tile forums will give you lots of good advice.
You were on the right track the first time with the wire lath and doing your own float. Thats how the pros do it. Duro rock is for DIYs. Just paper under the wire, mix a nice stiff batch of portland and sand and ad-mix, Tool it in and screed it off. Solid, one piece, no seams no cracks, last 100 yrs.
When you talk about felt and lath, are you talking about a mortar bed job? That's generally an inch thick. You could easily use 1/4" CBU on the floor, no need for 1/2", but your 3/4" subfloor is probably inadequate and you make no mention of the floor framing and whether or not it's stiff enough to be L/720 or better.
Anyway, exactly what is the plan here?
David,
I'm laying 12X12 white marble in a master bath. I took up the old subfloor which was 3/4" ply which had 8X8 ceramic on it. After I pulled up just one tile I was able to just pick up every tile like it was a playing card. Not one tile had bonded to the floor. There is a 3/4 heat pipe that runs down the center of the room (layed on top of the joists) which must have heated up the thin set and made it set only to the tile. There was no wire lath or tar paper, nothing.
The joists are 2X10 (real 2X10) firred up an additional two inches (to clear pipes and stuff) I glued and srewed 3/4" ply and am tring to figure the best path to take. I've worked plenty with durarock, I just don't know how well I can do an old fashioned mud job. I just don't want to raise the floor to much. The tile is 1/2"
First thing to do is go to this link and find out if your floor framing is adequate for stone (or even tile):
http://www.johnbridge.com/vbulletin/deflecto.pl
Your previous tile floor probably failed because plywood is a lousy bonding surface for tile. You should install tile over mortar or backerboard. 1/4" is fine for floors. Backerboard does nothing to stiffen a floor or improve the structure, it is just a bonding surface. You probably need another layer of 1/2" ply over the 3/4" you already have, if you want to install stone. Thinset over chicken wire or lath over felt is a completely inadequate tile job, it will be doomed from the start.
When you use the wire, you just go the thickness of the wire (expanded steel) -- maybe 7/16".
So convenient a thing it is to be a reasonable Creature, since it enables one to find or make a Reason for everything one has a mind to do. --Benjamin Franklin
Not sure what you're saying.... that you'd use thinset 7/16" thick over wire, or you'd use a mortar bed 7/16" thick? Neither one matches anything I've seen done.
The "wire" is expanded metal mesh. It has an effective thickness somewhere in the neighborhood of 3/8". Staple it down, then go over it with your mortar/thinset, thick enough to where the trowel just grazes the wire.
So convenient a thing it is to be a reasonable Creature, since it enables one to find or make a Reason for everything one has a mind to do. --Benjamin Franklin
I've seen many tilesetters use expanded metal lath as a wire base for walls. They use "wall mud" which is sand, cement, and lime, and the total thickness is closer to 1". That is allowed to dry and then tile is thinset over it. I don't know if any thinset maker would recommend their product be used 3/8" thick over wire lath, and tile set directly to it in one step, if that's what you're describing. Thinset is generally described as being ~1/8" thick max under the tile, over either CBU or a mortar bed.
When I do tile, or hire a tilesetter, I always use specs from the TCNA handbook. If I have time I'll check and see if they have methods like what you are describing.
Probably the main reason for not using thinset would be cost, not strength or other properties.The assembly I described is certainly as strong and stiff as an equivalent thickness of cementboard, and should be equally good for bonding the tile to.
So convenient a thing it is to be a reasonable Creature, since it enables one to find or make a Reason for everything one has a mind to do. --Benjamin Franklin
What you're describing seems like a lot of work compared to screwing down CBU over thinset, and you'd have to be good to get it as flat as CBU will be. My main concern would be whether or not the thinset manufacturers would approve the method.
I can't compare it to using cement board since haven't done any floors since the cement board for floors came out. It wasn't that hard -- worst was cutting the stuff to fit, working around/under an in-place vanity and around the pot pipe. Getting it level isn't that hard -- make sure the subfloor is level, take any kinks out of the wire before installing it, and be careful to not buckle it with the staples. Then skim with thinset -- the wire controls the thickness, so if the wire is flat the thinset is flat.
So convenient a thing it is to be a reasonable Creature, since it enables one to find or make a Reason for everything one has a mind to do. --Benjamin Franklin
Oh, and the tile is set in a separate step, after the thinset on the mesh has set.
So convenient a thing it is to be a reasonable Creature, since it enables one to find or make a Reason for everything one has a mind to do. --Benjamin Franklin