Replies

1. 
   razzman | Feb 26, 2006 09:16pm | #1

   Greetings c,

   This post, in response to your question, will bump the thread through the 'recent discussion' listing again.

   Perhaps it will catch someones attention that can help you with advice.

   Cheers

   'Nemo me impune lacesset'
   No one will provoke me with impunity

2. 
   FastEddie | Feb 26, 2006 09:41pm | #2

   The difference in height will only be a problem for you ... we don't care.  :)

   How much of a difference will it be?  If you can bevel the edge of the higher material, or install some type of transition threshold, then it should be ok.  But if the floors differ inn height by more than about 3/4" it will feel funny.  Also, be sure to allow room for the door to swing.

   Why do you think you need a backerboard?  If the issue is carck control, consider a membrane like Ditra, which is less than 1/8" and will reduce the problem.

    

   "When asked if you can do something, tell'em "Why certainly I can", then get busy and find a way to do it."  T. Roosevelt

   
   

   ---

   Edited 2/26/2006 1:45 pm ET by FastEddie

3. 
   andybuildz | Feb 26, 2006 09:50pm | #3

   Like Eddy said...ain't a problem for us if it ain't a problem for you...lol.
   Thats "your" call. Pictures of the room would help here. You can always use a new saddle and cut the saddle to allow the tile to butt up to it rather than the saddle to go over the tile. How's the height for your radiator? Other than that I can't think what any problems there'd be.
   Also, you could use some "Ditra" instead of a CBU. Its much thinner and nicer to work with if you can get any near you. It comes in rolls and is light as a feather. Personally, I love the stuff.

   If Blodgett says Tipi Tipi Tipi, it must be so!

1. 
   carver | Feb 26, 2006 10:33pm | #4

   Thanks for the feedback.

   I guess I was hoping for a considered opinion about irregular floor heights in adjacent rooms; I am quite sure "you" do not care.

   Also I was worried that the plywood subfloor would not be rigid enough to prevent cracking of the tile or grout. I am not familiar with Ditra(?). I figured I would have to put down concrete backer board.

   I have forced air heat so radiator height is not a concern, I would lift the toilet off, put the tile down, replace toilet so that is not a problem. Should the tile go under the sink cabinet or not?

   The space is maybe 10 by 12 including the shower, tub, cabinet and linen closet so it is not a lot of tile.

   Is this something that I as HO could do?

1. 
   razzman | Feb 26, 2006 10:37pm | #5

   carver,

   Here is some info about Ditra. 40209.1

   Cheers

    

     

    

   'Nemo me impune lacesset'No one will provoke me with impunity

2. 
   zak | Feb 26, 2006 11:01pm | #6

   I don't think differing floor heights are a problem, especially in a bathroom- I like to have a threshold a hair higher than the tile anyway, so that small spills won't make it onto the wood floor. It's really a preference issue. You may find that when you rip up the vinyl, there is an underlayment that you can take out also. when you add ditra or 1/4" hardiboard and the tile, you are almost at the original floor level. You'll want some sort of threshold to transition from tile to your other floor visually, even if it is flush. You'll need to find the thickness of your subfloor plywood, and the joist spacing (16", 24", etc.), and the size and span of your joists. Especially with large natural stone tile, deflection has to be kept to a minimum to avoid cracking. Backerboard or ditra will not make the floor any stiffer, it's just a good surface to attach to.You should really take the toilet up and tile under it if you want this to look decent. It's really not that hard to remove and reset a toilet, in fact it's much easier than cutting all the tile around the toilet to perfectly match the outside of the base. Find more information on the structure and come back with more questions- somebody here will have all the answers you need.zak

1. 
   carver | Feb 26, 2006 11:10pm | #7

   Thanks.

   I will take up the toilet. I believe the subfloor is 5/8 OSB on 16" 2x6 or 2x8. I am pretty sure the existing vinyl is laid on the subfloor.

   The adjacent floor is carpet. If I have to I can make a threshold piece.

   Should I also remove the sink vanity before putting the tile down? I plan to replace it anyway so I guess it is sort of a no brainer. How about the tub?

1. 
   BryanSayer | Feb 27, 2006 06:35am | #19

   You do know that besides pulling up the toilet and tiling underneath, you will need to raise the closet flange, right?

2. 
   andybuildz | Feb 27, 2006 07:04am | #21

   I forget what its called but they have now instead of a wax ring an adjustable seal he could use I think.If Blodgett says Tipi Tipi Tipi, it must be so!

3. 
   BryanSayer | Feb 27, 2006 07:19am | #22

   Yeah, I know those extended wax seal things exist. But then again, it isn't my house...

3. 
   andybuildz | Feb 26, 2006 11:40pm | #10

   I see you've gotten quite a few responses since my post so I'll just throw in ...if you think that a CBU adds strength, it does not. Its just a backerboard, however, in spite of what anyone might tell you, you CAN in fact use plywood to thinset tile to if you want to add more strength yet can't add more floor joists. You would need to use the proper plywood. CDX which is an exterior grade plywood works for this typ application.
   Good luck bro
   a...If Blodgett says Tipi Tipi Tipi, it must be so!

1. 
   carver | Feb 27, 2006 12:19am | #11

   CBU as backer board serves what purpose then? Even the surface? Stiffen the surface? More receptive to the thinset adhesive?

1. 
   FastEddie | Feb 27, 2006 12:51am | #14

   Hardiebacker or cement board do two things: they raise the finish floor height, and they present a very good bonding surface.  Sometimes people need to raise the tile a bit, so addng a layer of hardie is a good choice.

   You said you have 5/8" ply subfloor.  That's a bit weak.  It all depends on the size and spacing of the floor joists, but generally speaking you would want an inch of subfloor.

   You mentioned osb sub-floor.  That's a really poor base for tile.  You will need to add somehting, like a layer of hardie, or Ditra, or underlayment grade ply.

    

   "When asked if you can do something, tell'em "Why certainly I can", then get busy and find a way to do it."  T. Roosevelt

   Edited 2/26/2006 4:55 pm ET by FastEddie

2. 
   andybuildz | Feb 27, 2006 02:02am | #15

   From what you're discribing...as I said before if you can't add more floor joists from below I'd add another layer of 5/8" CDX plywood glued with PL Premium to your existing floor and then screwed together. Assuming the height wont bother anything,,,and if you do it as I described before as well...."butting" the ply to the saddle rather than putting the saddle over it you shouldn't have aby height problems.
   To me, and its simply a matter of taste...the height differance that minimal wouldn't bother me from one room to the next "especially" if it was just a doors width we're stepping through.
   I mean does it bother you when you walk from a room of carpet down into a room of just the harwood floor? Probably not, right? Same differance.
   PS...I don't believe you've said but I'm assuming the soapstone tile is approx. 3/8" thick or less?If Blodgett says Tipi Tipi Tipi, it must be so!

3. 
   carver | Feb 27, 2006 03:00am | #16

   They seem to range from 1/3 to 1/2 depending on the supplier.

4. 
   zak | Feb 27, 2006 04:43am | #17

   Where are you getting your soapstone tile, anyway? Local supplier or online? I think i'll do a countertop of honed slate or soapstone, I haven't decided yet.As others have said, I wouldn't lay that stuff over 5/8 OSB- a little to thin for 12" tile, IMHO. Have you measured the span of those 2x8s yet? That could be an even bigger factor.zak

5. 
   andybuildz | Feb 27, 2006 06:07am | #18

   HAd another thought about the rigidity of your floor. If you find you need to beef it up but have too hard of a time getting new joists in you could probably add another girder under the center of the existing floor joists if accessible but you'd still need to glue and screw on another layer of subfloor over your existing one. I'd say 1/2" at the least to feel safe.
   Just a thought...If Blodgett says Tipi Tipi Tipi, it must be so!

4. 
   philarenewal | Feb 26, 2006 11:13pm | #8

   I had exactly the same question not long ago.  The expert consensus was that it's chancy to tile over vinyl and I needed to do it for a customer so I decided the better path was to remove the vinyl tile.  If you're doing it in your own home, you might want to take the chance (if it fails it won't ruin your reputation, just an expensive lesson).  Here is a link to a very valuable resource that can help you determine if your subfloor and what's on it measures up to what is needed for tile.

   http://www.tileusa.com/faq_main.htm

   If you do decide to do it, one recommendation given to me was to check out the Mapelath product.  Again, I decided not to try it as if it cracked my customer would be very unhappy.  But in your own home, you have more latitude to try things out.

   Best of luck.

1. 
   carver | Feb 26, 2006 11:25pm | #9

   Thanks.

   I am sorry, I had no intention of tiling over vinyl.

   I just doubt that the builder put anything over the OSB before putting in the vinyl or the carpet in the adjacent hallway. So I was concerned that putting CBU down, then tile would yield a distinct and undesireable floor height difference.

1. 
   philarenewal | Feb 27, 2006 12:42am | #12

   Ah -- good.  eliminates the vinyl in the equation.

   If you don't want to bring the floor up to stiffen it, can you get underneath it?  While not a TCA recommended practice, I have successfully cut plywood to fit between the floor joists, and supported it with 2x cleats nailed to the joists, then screwed the layers together.  If you go this route, don't forget to use subfloor ahesive to tie the layers together.  Again, not "best practice" but I've done it where I had no other choices. 

   I'm not sure if you can get away with adhering tile directly to OSB.  Seem to have a vague recollection that it's not recommended.  If that's the case, maybe check out the product that Tavy raves about (Tavy Thin Skin).  I've never used it so I can't give you any more insight, but if it does what is says, looks like exactly what you need.

   Again, best of luck.

5. 
   plumbbill | Feb 27, 2006 12:46am | #13

   To your original question of differing heights.

   How thick is the soapstone?

   My soapstone countertops are 1-1/4" thick from http://www.soapstones.com/ 

   They have tiles too I'm not sure how thick they are---- that is going to be the biggest part of room floor height differential.

6. 
   en2ohguy | Feb 27, 2006 07:01am | #20

   having read all the posts so far, and based on your replies, here is what i would do if i was hired to install your floor.  First, i'd check for deflection under normal load. if it is more than 1/16ths i'd try to get underneath and sister the joists at least in the heavy load (tub/toilet) areas, and the high traffic areas. if this is not an option, then the next best fix is to install new subflooring.  essentially you will remove all your fixtures and take up the osb. replace it with 2 layers of 5/8 cdx tng. first layer pl'ed to the joists and nailed. 2nd layer placed at 90 degrees to the first, again pl'ed and screwed with 1 1/4 floor screws on 12" grids. it is during this phase that you will level the floor. if you have radical joist differences you can string off the joists and shim prior to laying in the first subfloor layer.  re-install the cabinets and tub/shower.   even though you can bond thinset to cdx i would rather apply ditra or superseal as a bond breaker to ensure good grout health and no tile cracking. tile it up (around the cabinets...makes no sense to waste money on tile you will never see) and grout it off. as to the height difference, prior to setting the tile determine your differential and either raise the existing saddle or, as i commonly do, mill one up using a table saw and router to profile the piece. finish it with whatever stain you like, 3 coats of poly and blind nail or screw and plug it down. you might have to used a horned flange seal when re-setting the john...after that new baseboard and trims....there you go...2 days, new loo...

1. 
   FastEddie | Feb 28, 2006 12:20am | #23

   First, i'd check for deflection under normal load. if it is more than 1/16ths

   How do you propose that the OP check the deflection?

     

   "When asked if you can do something, tell'em "Why certainly I can", then get busy and find a way to do it."  T. Roosevelt

1. 
   carver | Feb 28, 2006 02:41am | #24

   How about this;

   take a barbell put on 225 lbs., 

   lay a long straight edge on the floor,

   strap 1 sq ft pieces of 3/4" plywood to your knees,

   kneel down,

   hold the barbell upright (on end) about 6" from the straightedge,

   and check the space below the straightedge with a feeler guage.

   How's that?

   Why do I have to take up the existing OSB? Seems like that would weaken the floor where the rest of the sheet is laid.

1. 
   FastEddie | Feb 28, 2006 04:37am | #25

   My point was that trying to measure the deflection is a waste of time and inaccurate.  What you need to do is calculate the deflection based on the underlying structure.  All you need is joist size, spacing, span and species, and the type and thickness of the subfloor.

     

   "When asked if you can do something, tell'em "Why certainly I can", then get busy and find a way to do it."  T. Roosevelt

1. 
   en2ohguy | Feb 28, 2006 06:34am | #26

   Measuring deflection is simple and necessary if you want the installation to last. One method is to use the underside of the joists. Simply attach a length of masons twine to each end of  a joist in a high traffic/heavy load area. Ensure that the string is flush with, but not touching,  the bottom chord. Have a helper or the homeowner walk normally in that area while you carefully observe movement. After directing the load-test dummy  (intended to be somewhat humorous) to make several passes, you should be able to see if there is any movement. Gauging the movement is as simple as extending your tape so the end is firmly against the underside of the flooring next to the joist you are checking, and the blade is next to but not touching the string, extended slightly deeper than the bottom chord under no-load. Watch as the load is moved around and the movement occurs. Not many tile products will withstand repeated movement of more than 1/16th, even if a latex-modfied thinset is used.

   A second method is to assess the movement from the surface of the flooring. This is not as accurate but still gives you an idea of how stable the substructure is. A long straightedge such as a 7 ft level laid across the floor will be the constant. In order to see the depth of the deflection you get down at floor level and watchas the load is moved. Again, this is not as accurate but will still let you know if you need to do something to control the bounce.

   If no helper is available for either method, use the bathtub. Fill it with water and as it drains look for movement if using the topside method, and if under the floor you will see pretty clearly if the weight of the water is pushing the joists down.

   Span charts are great for planning and framing but they do not take into account age, wear, rot, poor installation and other factors such as pass-throughs drilled improperly.

   Edited 2/27/2006 11:42 pm ET by en2ohguy

2. 
   en2ohguy | Feb 28, 2006 06:54am | #27

   Taking up the OSB is the option I would use if you can't get at the joists to sister them (finished ceiling below, etc...).  It's simple to do, a bit of a pain but as long as you have walls that are nailed though the sheet into the joist you have no worries about weakening the sheet, just use the sawzall( recip saw, if you prefer) and carefully cut the perimeter at the bottom plates. I do this a lot and have never had a problem with the flooring in adjoining rooms. If the floor is properly fastened to the joists, nothing can happen.  When making the cut you have to keep the blade at a very shallow angle to avoid wires or pipes that might be lurking in the joist spaces below. I have found  that a 6 to 8 inch rescue blade is the easiest to control and even though it's slower than a wood-eater, the thicker blade depth seems to make it a bit more durable and less likely to break. But you still might go through a couple of them while you're cutting.

   I haven't tried that dumbell/plywood square thing...if you decide to give it a shot let me know how it works out.