I’m tiling a shower using durorock. Can you use the tinset morter to remove some imperfections in the wall, before I tile ? Need to build up 1/4 inch, and the transition from duro to sheetrock is flush, tape and use thinset or hot mud /setting compound?
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fiberglass tape and plani patch would be one product.
Tim Mooney
Thinset mortar is designed to be used thin, approximately 1/16" is ideal for most mixes. It's strongest when used thin. Tilesetters do use it to build up areas sometimes, and I suppose 1/4" would not be a crime, but thinset is not made as a filler material.
I don't think you need to join the durock and the sheetrock with tape. I assume your sheetrock is 100% outside of the shower or well above the shower head and you are only going to overlap the last tile onto it. If you are going to run courses of tile onto sheetrock you should take it out and put in durock instead.
Last time I did a shower the last course of tile vertically was a surface bullnose and it lipped onto the sheetrock outside the shower door by about 1". I primed and painted the sheetrock first, the tiled onto it. To finish I grouted and then caulked the back edge of the tile to the sheetrock with grout caulk.
>>Tilesetters do use it to build up areas sometimes, and I suppose 1/4" would not be a crime, but thinset is not made as a filler material.
Is there any product out there specifically designed for building up floor up to 1/4" may be even up to 1/2"? I am talking about uneven build up say from 1/4" to knife edge. Thank.
yes ... lots.
what's the final floor covering?
again ... try http://www.mapei.com .... or a local tile store ... not HD or Lowes ... for the latest. Both Mapei and Custom have what ya need for under a tile floor ....
For under other surfaces ... Dependable is a great all around floor leveler.
All depends what type of floor your building up and what you're planning on covering it with.
JeffBuck Construction Pittsburgh,PA
Artistry in Carpentry
Jeff
Just to get off the subject a bit.
I frantically finished my 2nd floor laundry room yesterday before I head out to go skiing...used Ditra and 6" tumbled marble.
I sealed it twice this morning and moved the washer/dryer back in and ran two loads.
The entire 2nd floor vibrated when the washer was on spin "before" I put the Ditra and tile down.
After the tile and Ditra I feel no vibration at all, not even in the laundry room.
I reallyyyyyy like that Ditra product.
I believe it cushioned the vibration of the floor.
Be well to you and yours this Xmas
andyMy life is my practice!
http://CLIFFORDRENOVATIONS.COM
>>All depends what type of floor your building up and what you're planning on covering it with.
The sub-floor is 3/4 T&G CDX and it's about 3/4" out of level over 10'. Joists 16 OC. So I figure I have to build up the floor with some 1/2" and 1/4" ply, then fill and level with something, then cement board, then 16" granite tiles.
Does that sound like a viable solution or can you suggest a easier/better way?
Thanks.
First, 3/4 cdx over 10 feet might not be stiff enough for any tile job. What are the size of your joists? What is the total span? Let me know.
Assuming it is, a 3/4" elevation change over 10 feet is huge. Sounds like the home as settled quite a bit. A couple of ways to skin this cat:
1. Carpenter Fussy Method. Using shims, scraps of plywood and the like, try your best to level the CDX. If you do this with the existing CDX in place, it will look like H e l l . The backer board will have dips and humps. It can be done, but it will be fussy, and ya'all better be good and very patient. I am neither.
2. Carpenter Better Method. Rip off the CDX. Replace the CDX with inch and an eight T&G Sturdy Floor. Use sister joists (scraps of 1x8's or 1x10's next to the existing out of whack joists) to straighten up the floor with an 8 foot level. Then nail down the decking nice and flat. This would have the added benefit of making a stronger and flatter floor (see problem above). You can tile right to this stuff if you use a membrane like Ditra from Schuleter or some quarter inch Hardibacker. You will gain elevation. This is about a $300 problem, and can be done. The Ditra will run you about $3 a foot.
3. Tile Guy Method. Assuming the CDX is strong enough, lay down some felt, some 3.5 diamond lathe and make a mud bed about 3/4" at its thinnest point, and no thinner. You instantly have a dead flat floor that is perfect for tile. Cost is about $100. This is what I would do. It is super cheap, dead flat, and a perfect setting bed for tile.
4. Have and SLC Party. Lay down some poly and 3.5 lathe, then get a whole bunch of SLC ($30 a bag), and invite some friends over with buckets and drills. Mix it all up at once in about 2 minutes, and no more. Pour it all down at once in one minute, no more. Move it around a tad with a rubber squeegee but just a little. Let it find its own level. It will be more or less level but will set up in only five minutes. You don't have much time.
SLC--two lies in one. It doesn't self level, and you can't do it yourself. You will have to put up 1x dams to contain it and seal every crack. This will be expensive.
My favorite SLC story is the 200 square feet of SLC I was doing about 10 years ago, and we missed a seam in the subfloor, so we have about 10 guys with drills and paddles and buckets and dump 50 gallons of the stuff in an upstairs bath and notwithstanding my precise calculations as to the amount, it isn't even close. We are short by another 25 gallons at least. I am scratching my head and wondering what happened, when the lights flicker and the power pop and I hear a scream
J e s u s F u c k i n g C h r i s t ! The homeowner is watching TV downstairs, and about 15 gallons of this soup is streaming out a light fixture.
We had to tear it out below the subfloor and chisel out the rock hard SLC out of the joist cavity, insulation, the electrical box, the light fixture and his nice hardwood floor. I missed a seam in the plywood subfloor. Sigh.........
Regards,
Boris
"Sir, I may be drunk, but you're crazy, and I'll be sober tomorrow" -- WC Fields, "Its a Gift" 1934
O.K. Boris, let's start over. Joists are 2x10, 16 OC, span 13'. The original 5/8" sub-floor was more than 30 years old and starting to delaminate in more than a few places. I knew we needed to build up the sub-floor so the 5/8 was removed, dumb enough never thought of the floor being not level, 3/4 CDX was inset between joists on 2x2 ledgers glued and nailed to the joists so the top of the ply is at the same level as the top of the joists. The CDX was glued and screwed to the ledgers and the resulting floor feels solid.
Removing the ply and sistering in joists are not something that I want to undertake at this point. So #2 is out of the question.
#3 sounds like the best solution but there is a problem. I had two tile guys looked at the job before the removal of the 5/8's and they both told me to screw down the existing 5/8's and they would put diamond lathe and skim coat it with thin set then set tiles on top. This seems to be standard practice here but I never feel comfortable with that. So I will have to keep looking and hopefully I'll get somebody who talks the same language.
Or I just may have to resort to #1. In that case I intend to level the floor with 1/2 & 1/4" ply and thin set and fill in the resulting dips and humps with some kind of compound (any suggestion?) before the backer board is put on.
Once the idea of SLC crossed my mind and since then I had nightmares about spilling over the dam or leaking through a seam.
Boris, your story would make the inside cover of FHB.
Again thanks.
Your floor is L458 by my calculation, which is fine for tile, but not for natural stone. Lose the granite. It will crack. If you want to use natural stone, you will need another half inch of ply.
There is no way I would "skim coat" the tile. That practice, while common is not approved and will ultimately fail, because thinset has no compressive strength. The Ditra would be a better method, but doesn't solve your out of level problem.
If you can live with an elevation gain, float a mud bed. I can give you step by step if need be. It is stupidly easy and as cheap as a couple bags of portland and sand.
Another point, there is flat but out of level, and level. Many folks with older homes can live with flat and pitched, and there is nothing wrong with that. As long as there are no humps or dips, you will have a fine tile floor. So if it is indeed flat, and you can live with that, then just buy some Ditra or quarter inch Hardi and tile away.
If there is a dip or hump (a straightedge will tell you that) then there is no way I would attempt tile without straightening the floor. The advantage of an SLC is that it can be very very thin at the edges and still have compressive strength. So if you are high at the door and low in a corner, SLC might be the way to go. Just some 10 mil poly or go overkill with ome roofing cement and Aquabar paper (thats what I use) and that will seal off the room fine. It is however, very expensive and you will need some help. All of it has to be mixed and put down in about 5 minutes.
There are commercial floor leveling companies that mix it in a truck and pump it to your location in the home. They tend to specialize and I have had very good luck with those outfits. Big bucks, though.
The bottom line will depend on whether your floor is straight. If so, and you can live with it, tile away with a membrane. If not, then you have two choices, mud or SLC. Good luck, and let me know how the project comes along.
Regards,
Boris
"Sir, I may be drunk, but you're crazy, and I'll be sober tomorrow" -- WC Fields, "Its a Gift" 1934
Thanks for your patience, you make a really good teacher.
The floor has no marked dips and humps but it's not flat either. It's kind of a gentle parabolic curve in cross section either way. I am really leery on my ability to throw a SLC party without messing up big time. I have no problem with the beer part but the rest? I don't think so. So my feeling would be towards a mud bed. Elevation gain is not a problem, I have 1 3/8" to play with and can even increase it a bit with transition thresholds. I have an idea of how to float a mud bed but I have never done it before. So give me the low down if you can, step by step, much appreciate it.
If I float a mud bed do I still need the extra 1/2" ply for granite? BTW, can't let go of the granite, it's been sitting here long enough that it's well acclimatized.
Edited 12/22/2003 12:39:15 AM ET by TOMCHARK
You are well short of the L700 (an engineering measure for rigidity) required for tile. The mud bud will add some stiffness but probably not enough for granite.
There is a deflecto-meter where you see for yourself what your floor is and it is located at: http://johnbridge.com/vbulletin/deflecto.pl
This is how a make a mud bed. The tools you will need are a masons hoe, a mud trough, some buckets, several levels, some 3/4" galvinized pipe, several straight edges and a wooden trowel. For materials you will need some sand, some portland cement, poly, and some diamond lathe.
Mix 6 parts sand to 1 part portland cement in mortar trough on on a clean driveway. I use a mason's hoe to chop the two components together. Add water very very gradually and chop it together. The consistency you are looking for is very very dry but it will barely hold together in a ball when you squeeze it.
Before you add the mud you will need to prepare your floot. Have an idea what the final finished elevation will be. You might want to have a nail or a piece of scrap wood at a particular location that will be final elevation.
The floor should be clean and covered with poly and 3.5 diamond lathe tacked to the subfloor. Carry the mud upstairs in 5 gal buckets and dump it at the elevation point you've decided. Get that right and remove the nail or the wood. This pile of flattened mud now determines the elevation of the rest of the floor. I call this the boss line or the boss pile.
Get 2 long 3/4" pieces of pipe and lay them on the floor on top of a small pile of mud and adjust one end with a long level so it is level with the boss pile. Then level the whole pipe, and repeat the same for the second pipe, which is about 4 feet away and parallel to the 1st pipe. Now you have two perfectly level screeds.
Fill the middle, pack it down with a wooden float (I really slap the surface), and strike it off with a straight edge. Go back over the surface with a level or straight edge, to spot dips and humps and fill those in and pack the patch down with a wooden float.
Continue the mud bed, by sliding down the pipes and re-leveling those with your boss pile. For the edges you will need a smaller straight edge and you'll work off only one pile.
When you are through, cover the mud bed with paper and let it cure for a day. I like to get on in the next day and again check for flatness and while it is still damp, again fill in in any dips with Custom's QuickFix and shave off any humps with a steel trowel. It is easier to do this the next day, while the mud is still soft.
You can tile on it the next day, or wait.
For details on the above process, there are some free instructions at
http://johnbridge.com/vbulletin/ or you can buy Michael Byrnes book or another book by John Bridge. Both are excellent books.
Good Luck!
Regards,
Boris
"Sir, I may be drunk, but you're crazy, and I'll be sober tomorrow" -- WC Fields, "Its a Gift" 1934
Edited 12/23/2003 12:27:25 PM ET by Boris Yeltsin
Sure can use all the info, thanks Boris.
As your best advice so far go with #3, it's just like you were planning on doing that now any way and your just at the lay the felt step, get the lath and your on your way.REad READ REad so you know what the steps are. Mud job will give you the best results with the least amont of steps with some of the biggest mess.
Clay
Thanks for the encouragement. Now and then I just need a kick in the butt to give it a kick start.
Definitely try the mud bed. I'm just a tile hacker, but I just did that in my bathroom where the floor sloped an inch from front to back. I dropped the floor down between the joists so I could get between 1 1/4 and 2 1/4 inches of mud without a huge step at the door. Make sure you have a helper to mix the mud while you spread, and you will end up with the best floor in you house.
Thanks for sharing the experience. Now it doesn't sound as intimitating as before.
If you read enough to get it in your mind what the steps are it helps. Look at the map and if your like me, write down the steps cause the brain can't remember more then when's dinner.
Break the project into small pieces and it isn't so over whelming. Also look at the finished project before you start, and live up to that finished standard all along the path to compleation. If you do tile often enough any time your not happy with the job you know exactly where you compromised on the project and when that happens stop and recharge your brain. It's not the end of the world to restart another day.
And the last thing that's good and bad about tile is when it's done it's gonna be there for awhile, so take the time to get it right the first time.
Clay
I read Michael Byrnes'(sp?) book a few times and John Bridges' as well. I am thinking of getting the TCA handbook and go over it before I start.
You're right. I am going to write down the steps on the wall in big prints for easy reference and save me from fiddling on little pieces of paper.
Two things, after your all ready to start the mud make sure you have a couple of nice straight screed boards of different lengths so they are easy to draw across the level floats. The floats could be pipe or wood, and you can pre screw in place and level perfect then take them out after and pack the voids. Use dryer mix, and I would recomend create additive not thinset additive, It's almost as thick as old STP on a cold day. And the mud for the float job is not thinset.
The tendency is to try to go to fast but you have lots of time to pack and screed so you can go at a easy pace.
OK thats more than 2 but you get the Idea. Plus your gonna have to post a picture or so, we wanna see.
Clay
You are really rushing me, aren't you? Don't expect to see the finished job for a while yet, I have to psych myself up first.
Where do I get straight screed boards and floats? Do you soak them in water first like when you are doing plaster?
Look in the pile of 2x4s or 1xs and use some straight ones. If your reusing floats we use redwood, but hey it's one job. Don't let them stay in place to long and work in smaller sections, pull them out and pack the voids and level. Work in manageable size sections and make the floats in pieces so you can pull them out as you go. Also see that corner of the room opposite the door, don't work in that direction work towards the door ( ha Ha) just funnin. It would be nice if you had some one to help mix the mud so you could be floating it. It just makes it harder if your a one man band on that stage of the project.
Plus don't over analize it, look at the big picture.Your making a big tile picture and you want the matt to be unified so the picture stays in tac over time.
Clay
Edited 12/23/2003 6:46:42 PM ET by Clay
>> Plus don't over analize it, look at the big picture.Your making a big tile picture and you want the matt to be unified so the picture stays in tac over time.
Hmmmm... it's like driving where you look down the road instead of the patch of asphalt in front of the car.
Things are slowly sinking in, thanks.
ROAR!
yes you can to all your questions.....a 1/4 " is a bit heavy but I think it'd be ok.I've done it in the past with no problems....I hate to keep saying this cause it sounds like I'm selling something but use a liquid latex mortar additive and not water to the thinset......NOT the thinset that calls ONLY for water.
Its amazing stuff. The additive.
BE well or a wall or a .....ahhhhhhh happy new year
andy
My life is my practice!
http://CLIFFORDRENOVATIONS.COM
OK ... let's take this one at a time .....
build up thinset 1/4 ... no problem.
Let's keep in mind ... the most used trowel is a 1/4 notch ... so .......
Now ... what are ya building up 1/4?
would it make more sense to use 1/4 backer board?
As to the flush transition ... most definitely tape and thinset.
I prefer the self adhesive tape. Then fill in and flat trowel with a 6 inch knife.
The ideal tile layout has the edge tile breaking right over the backer/drywall seam.
every and any joints should be taped and thinsetted.
I prefer Mapei Ultra. It's a modified thinset ... mixable with water. Plenty sticky for most tiles ... a latex aditive isn't necessary unless you are working with a difficult tile or substrate ... like say slate or marble .... then I'd skip it all togethr and go to a marble thinset or their kerapoxy line mixed with their kera-additive which is another pain in the ####. Consider those trowels disposable.
check ... http://www.mapei.com they have a complete breakdown of products and applications.
Now I gotta ask .. why the imperfections in such a small area? A shower surround. Better to shim the durorock with shims and liquid nails .. or sister studs .. for perfect plumb/square first ... quicker too.
Even if the first round of backer was hung ... think about it.... U can probably reuse the duro .. just retape ........ Get the framing straight ... then move on.
Don't forget the vb .... I like felt .... some like poly.
Jeff
Buck Construction Pittsburgh,PA
Artistry in Carpentry
"The ideal tile layout has the edge tile breaking right over the backer/drywall seam."
How are you going to get a nice finish on a joint like that? The last tile should lap over the rock by an inch or so to conceal the joint. 75% +/- of the tile is glued to the CBU, and it's back-caulked to the rock after setting.
Also don't agree that you can glue the CBU and rock together with mesh and thinset. The relationship of those two materials is mostly irrelevant, aside from making them flush. The joint may move slightly, and if you've set the tile correctly you don't care.
OH ....
so ya mean like ...
having that last "edge tile" ....
"break .... right over the seam?
Gee ....
why didn't I think of that?
While were on the subject ...
that joint probably will move slightly ....
that's kinda what the mesh tape is for ....
to keep the tile from cracking or loosening above that crack movement.
and...
yes .... thinset ... particularly Mapei Ultra ... sticks just fine to drywall.
And ... if the layout is off ... or more likely the homeowner makes yet another design change ... you can alos reverse the process and duro-rock right over the now exposed backerboard for a nice smooth plaster like finish.
Jeff
Buck Construction Pittsburgh,PA
Artistry in Carpentry
You could use medium set mortar
http://www.ntlfloortrends.com/CDA/ArticleInformation/features/BNP__Features__Item/0,2915,82308,00.html