Any professional tilesetters in here - Ditra Mortar Coverge

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MTcummins

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You have no need for a waterproofing product such as Noble in your application. If you install those 32" tiles directly on wood, they will almost certainly pop off when the wood underneath expands and contracts. A product like Ditra will give some degree of waterproofing by default, but that is not its purpose... the sheet itself is waterproof, but the seams are not unless you go through an annoying process to make them water tight.

JW may not believe in uncoupling, but its a very simple concept that both Ditra and his own advised product Spider Web use... they separate the 2 layers that expand and contract different amounts and at different rates. Tile does not expand/contract much at all, and takes a lot of temperature change to do so, where wood expands and contracts a good bit at much lower temperature changes. The idea of uncoupling is to allow the 2 surfaces to move a bit, independent of each other. It is a concept that is thousands of years old... the oldest surviving tile installations in the world only survived because they decoupled the tile from the substrate.

The other way of doing it is to screw a similarly expanding/contracting substrate (such as CMU or Hardi or whatever) to the floor first, then attach your tile to that, so that they will expand and contract at the same rate. This can create stresses between the wood and the backer board, but usually is not a problem unless there is extreme temperature swings.

Both methods work well and have been fairly well proven. I personally am a Ditra guy, but would be interested to see a Spider Web install sometime (I've never seen the stuff used, to date), and see how it holds up over time. Sounds like a good alternative in the price department (though once again, I find JW's Schluter pricing to be very off, I pay under $1.50/sqft for Ditra), and the ability to use all modified w/o voiding warranty is appealing. Generally I use modified under Ditra to wood (proper), and modified over to set the tile (voids warranty), and leave a few days before grouting, especially if setting smaller tile. Larger tile (which I personally don't much care for and almost never use), this could be more of a problem. VersaBond has worked well for me, as it is not as highly modified, so it dries a little better than others when sealed off like that.

NOTE that I explicitly stated that doing this will void your warranty. It's how I, and a number of other people, have successfully used Ditra numerous times, but it is not manufacturer approved.
 

BobL43

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And thank you too mt for your explanations here which are very helpful as well. My son in-law used Ditra on their bathroom and said that putting down the modified and then the Ditra was easy, but he found troweling down the non-modified on top of it was a PITA for some reason I don't remember. I have been using the Versabond putting up the marble subway tiles on the walls, and find it is nice and easy to trowel out at the recommended mix consistency. John W's post #9 says he finds it easier to get the thinset embedded into the Spider Web waffle holes, which sounds good to me as well as being OK to use the modified. I will try and find a local tile company like John said that may sell me a remnant piece of the Spider Web matting.

Again, thank you both. :D
 

Jadnashua

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The points I made about SpiderWeb and the screed are direct from the company's technical data sheets...do you read them? They specifically say to call them about special requirements on tile larger than 12". They specifically state the screed must be used with aggragates suitable for your application and to take into account their moisture content when mixing for the proper mix. They specifically state that over a slab that it must be a minimum of 3/8" and over a subfloor 1-3/8". You talk about following the manufactuer's recommendations and instructions, and then you state other things.

If you have any imagination and technical experience, the decoupling provided by the Ditra is obvious. And, it is obvious why they indicate an unmodified to anchor the tile to it is more than sufficient...the tile/mortar acts as a monolitic slab that can move independently of the subfloor. It is also obvious with the SpiderWeb that it won't work without a modified, since it is only bonded to the fibers, some of which are actually designed to shear off rather than locking into the dovetails in the Ditra pockets. You only get their 10-year warranty with their SpiderWeb mortar...nothing I said was not direct from their materials.

If you are not also mixing their screed product with a suitable aggragate, you aren't following the instructions unless you are doing a thin layer over a slab and then must use their admix, not water. That aggragate is sand or gravel...you seem to have missed that, and not water - the product requires it to be mixed with an aggragate, that is not in the bad from the factory, i.e. another thing to buy. Anytime you buy sand or gravel, especially in bulk, not in bags, you must take into account how much water it has in it. Again, not reading what I wrote. I have no problem with any of the products...I have my preferences. You stated you could use the screed at 1/4", which is not true per the spec sheet. Maybe not much, but that's 50% error.
 
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JohnfrWhipple

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Bob you need to get a broader base of opinions. So many tile guys and online "contractors" just repeat what they read online. There is no measuring system for "Uncoupling" Noble Seal TS will outperform Ditra and Spider Web hands down and is an antifracture membrane. Noble Seal TS has been tested to surpress cracks over 3/8" but they recommend less as a safety net.

An anti fracture membrane should be three times the width of your tile. Nobel Seal TS is 60" wide not 37" like the others.

Call the tech boys at Noble and ask these basic questions.

Phone: 231-799-8000
Toll Free: 800-878-5788
Email: sales@noblecompany.com

I have meet personally both Eric and Nelson from their head office and these men know this business. They sit on chairs and are a wealth of information.

"Uncoupling" is a marketing sales pitch.

You are also using large format tile. 32" lengths. Non Modifed thinset has a very low expansion rate and suffers from mortar fatique. For large format tile an S2 thin set is recommended and offers in of itself some expansion. My favourite Mapei's Grani Rapid.

Once you decide on a system remember you need thin set to set your tile and then grout. Why not further protect your investment and check with your Laticrete, Mapei or Custom rep for their opinion.

Once you hear all the advice and listen past the marketing and the regurgitation of miss information or sales information a clear solution will emerge.

Messing up a bathroom can cause a major failure. Take the time. Call the reps and get your questions answered. Don't blindly follow online advice because it is quick and easy. Building a shower is hard. You need to have the right tools and right products. You can't do it right in a long weekend and their are rules and inspections to insure it's done right.

Always self inspect your work or the work of others. Ask for a 2-3 flood test. 24 hour at the bare minimum. Measure the level excatly.

I installed Ditra for over a decade. As I moved more and more into the barrier free shower installs and linear drain projects the restrictions of Kerdi and Ditra became unsurpassable and I developed better techniques, after more training and more guidance I have learned that chemistry in the setting materials is key. Timing and build up heights fine tune the system.

When something is sold as to good to be true - it often is.

Waterproofing a shower is not something you can almost do perfect. When it's perfect. It's good enough.

JW
 
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Chefwong

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Jim -

FWIW....there are a couple variants in Mapeis Mapecem lineup....

The Mapecem I used does not require aggregate. It was the Mapecem premix.
If I recall, it was speced at feather down to 4" which is quite impressive IMO.
Yes, they do spec their mortor or additive for the bonding slurry but aside from that, it's just plain H20 and that's it...
Great stuff . I'm sure John get's a trademans discount but I thought for what it does.....$19 per 50lb bag was pretty good.

Ultraplan 20 is really some nice stuff too. 2" self level and this product can be used as a direct exposed topper....
A lil pricier than where I budgeted this but I needed this right after thanksgiving weekend, and the only places open were a major supply house I use for other odds/ends.
It took awhile as I had to Cherry Pick 42 fresh bags off their pallets.. Local tile supply shop always has stuff that is fresh, but they were closed.

Just a reminder for those who stumble upon this thread - ALWAYS check the production dates on stuff like this. Any rapid setting product, you want made 6 months prior. Less is better..
 

MTcummins

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This floor is not going to have any water spilled onto it where I have to worry about it being waterproof

Once again, JW is not actually reading the posts he's responding to, just going off on his tirades. What the hell does waterproofing a shower have to do with the topic at hand (tiling a dry bathroom floor)? I also specifically mentioned that Ditra is somewhat waterproof as a sheet, but not at seams. Clearly we're not advising the poster to set up a slip-and-slide on his 7x7 bathroom floor installed with Ditra...

What, you don't have any smart-ass response to Jim when he proves you wrong? You're usually right on top of him, criticizing his every word...
 

JohnfrWhipple

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...What, you don't have any smart-ass response to Jim when he proves you wrong?...

When was that?


Jim tries his best to recommend the John Bridge forum and send those looking for answers away.

Jim often leaves out key bits on information that he believes the new be will figure out.

I'm offering up another opinion. One from someone in this business who feeds his family from doing this very trade.

You have your right to take offence but those looking for information should hear all sides. Regardless if you agree or disagree with my thoughts.

Jim pushes Kerdi hard. Just look at 30 old threads - you can see it.

Kerdi in my opinion the worst option out there with the best marketing team - they don't need Jim but he is helping.

I want to see a reduction in our landfills - much of it the result of poor building codes, dodgey contractors and those just doing a flip. It's wrong and I'm trying to make a difference. This is not new - I have been working at this for three years.

What are you doing to make a change for our kids?

JW
 
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MTcummins

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When was that?

That would be when he cited the manufacturers specs on many things that you were not following, after so many times soapboxing how you have to follow directions to the T.

It had nothing to do with Schluter. I won't get into a pissing match about Schluter vs non Schluter products, its pointless. Who's paying you to try to shut them down? I am curious though, how is it that you, who seem to think you know everything there is to know about tile/showers, managed to install Schluter products for a decade w/o figuring out that they're total garbage? That's a pretty darn slow learning curve for someone who is doing so much for the world, knows all the best stuff, etc. Not sure that your advice gives me much confidence if it takes you a decade to discover that the product you've been installing is junk. How long have you been installing SpiderWeb or NobleSeal, or any other products? Are we gonna hear from you in another 3 or 5 or 9 years how they're junk, even though you touted them so vehemently?

I have no problems with any of these products per se, just a problem with your blind hate for Schluter. They're a business, they use marketing. So does every other business, including every one that you like. That doesn't make their product garbage, or the (many) people who like it dumb. All of these options can be good options in some situations, and can be bad options in some situations.
 

Jadnashua

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The Mapecem I used does not require aggregate. It was the Mapecem premix.
If I recall, it was speced at feather down to 4" which is quite impressive IMO.

Both the Mapecem products are spec'ed for use over concrete. On the Mapecem (not the pre-mix) I was able to find the installation manual, and it said it could be used over a subfloor, but then it had to be at least 1-3/8" thick, needed lath and a decoupling layer (like tar paper) on the ply first. On a slab, at least 3/8" thick. If you can point me to the installation instructions for the pre-mix and the other screed (that I can't seem to find again), I'd be grateful as I'm open to learning.
 

JohnfrWhipple

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Thanks Chef Wong.

Slurry coat over concrete. Down to a 1/4". 1/4" to zero we use Grani Rapid.

For the recommendation I made under the tub I suggested building paper and diamond lath. You will not find those recommendations printed online Jim so there is nothing for you to cut and paste. Try calling a Mapei rep and asking him.

Back in the day this was a common practice. How thin you can go with your mortar bed is debatable since so many factors come into play. But over a ship lap floor topped with plywood I would think as low as a 1/4". If it just fixing the grade for a tub. Remember this technique uses the diamond lath with roofing nails to lock the system to the floor. Again you will not find specs like this online to cut and paste. Call setting material producers - they have staff on the clock to answer your questions. It's their job.

I am not paid by any company. I do this to make a difference. I'm trying to change an industry and in doing so help reduce our landfills some what. Unless your in this business you have idea the waste generated everyday. It is not a fun filed trip but hang out at a dump site and you will see how bad it really is.

Our building codes are crap. The skill set of our tradesmen alarming. And bogus online advice adding to the already bad situation.

My thoughts.

JW
 

BobL43

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I did not mean to start off any butting of Horns here.

You have no need for a waterproofing product such as Noble in your application. If you install those 32" tiles directly on wood, they will almost certainly pop off when the wood underneath expands and contracts. A product like Ditra will give some degree of waterproofing by default, but that is not its purpose... the sheet itself is waterproof, but the seams are not unless you go through an annoying process to make them water tight.

JW may not believe in uncoupling, but its a very simple concept that both Ditra and his own advised product Spider Web use... they separate the 2 layers that expand and contract different amounts and at different rates. Tile does not expand/contract much at all, and takes a lot of temperature change to do so, where wood expands and contracts a good bit at much lower temperature changes. The idea of uncoupling is to allow the 2 surfaces to move a bit, independent of each other. It is a concept that is thousands of years old... the oldest surviving tile installations in the world only survived because they decoupled the tile from the substrate.

The other way of doing it is to screw a similarly expanding/contracting substrate (such as CMU or Hardi or whatever) to the floor first, then attach your tile to that, so that they will expand and contract at the same rate. This can create stresses between the wood and the backer board, but usually is not a problem unless there is extreme temperature swings.

Both methods work well and have been fairly well proven. I personally am a Ditra guy, but would be interested to see a Spider Web install sometime (I've never seen the stuff used, to date), and see how it holds up over time. Sounds like a good alternative in the price department (though once again, I find JW's Schluter pricing to be very off, I pay under $1.50/sqft for Ditra), and the ability to use all modified w/o voiding warranty is appealing. Generally I use modified under Ditra to wood (proper), and modified over to set the tile (voids warranty), and leave a few days before grouting, especially if setting smaller tile. Larger tile (which I personally don't much care for and almost never use), this could be more of a problem. VersaBond has worked well for me, as it is not as highly modified, so it dries a little better than others when sealed off like that.

NOTE that I explicitly stated that doing this will void your warranty. It's how I, and a number of other people, have successfully used Ditra numerous times, but it is not manufacturer approved.

I appreciate EVERYbody's advice here based on their professional experiences, I really do. Ditra is sold at the Orange big box store for just under 83 bucks for a 54 sq ft. roll, (the local tile stores have it for sale at 81 bucks), which is just what I need, plus I have a piece from what my son in-law gave me left over from his project. As far as Ditra warranty goes, it covers material and labor costs for 5 years. Being that I am doing the labor myself, I have no labor costs to provide to Schluter as documentation if I need to make a claim on the product. The floor tile is going to cost me a big 300 bucks and a bag or 2 of thinset and the roll of Ditra. I definitely do not want the floor to fail, and I do not want to go nuts trying to spread out the mortar into the waffle holes. I asked my son in-law last night what the bad experience was with him using Ditra and he told me that it was 1) getting the thinset (unmodified) to fill in the waffle holes and 2) then getting the porcelain tiles to stick to the unmodified. I'm not sure why the tiles would not stick well, but he said he wound up removing all the unmodified and reapplied Versobond (modified) on top of the Ditra, and the tiles stuck very well (18X18 inch tiles, I think). Is there less "stickyness" of unmodified to tiles than modified? I know that the Versabond sticks very well to both my walls and the marble tiles I applied to them. I used to use adhesive for ceramic wall tiles, and the Versabond seems almost as sticky as that stuff after the tile is pressed in.
My son in-law had read that there would be a drying problem with the modified thinset on top, but he allowed lots more drying time before walking or grouting the floor. It's been over a year, and no cracked grout or loose tiles. So, it's a matter of the easy availability of Ditra in the right size roll, and "having" to use unmodified on top, vs trying to find a small piece of Spider Web and being able to use either their own or another modified thinset on top of it.

By the way, back in 1987, I built an addition to my house and I had a friend install about 600 sq feet of ceramic tile for me on top of the plywood subfloor I had put down. He used thinset and a latex additive, but put down no cement backer board or any membrane at all. In all these years, about 15 tiles have loosened, but they are in an area that was really hard to avoid walking on right after installation (he had cautioned us not to). these are mostly 8X8 inch tiles, but in the other room which is 16X10 foot with 6X6 inch tiles that got no "too soon" walking on, none have ever lossened at all, so I guess everybody's mileage may vary. I do want to do it "right" this time by myself.

Again, thanks to all including ChefWong for starting this thread.
:)
 

Jadnashua

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Modified is stickier. On any tile that large regardless of the type of mortar used, you really need to burn in a layer of thinset on the backside of the tile first, and this doesn't hurt on any tile, but often is unnecessary. Since thinset sticks to thinset, you get instant tack that way. The key is, some porcelain is quite smooth, and compressing a layer of thinset into the pores can be a little tough, much easier if the thinset is mixed properly and is a decent quality. SOme tile come with a mold release on them still, and that can make it even tougher for the thinset to get initial tack. When you are not mixing a whole bag of thinset (common for DIY'er), you may not get the right mixture. It is also not uncommon to fail to mix it properly.

A little story from a class at CTEF (essentially a tile school run by the Tile Council of North America): A manufactuer's rep was visiting a pro who had complained about one of their products. The pro was complaining that the stuff wasn't smooth and had a lousy texture. The pro watched as he mixed up a batch and then started setting tile. The pro said he'd get back to him. A month or so later, the rep came back with a bag of thinset and asked the guy to try it; said it was a 'new' bag formula. The guy started to mix it up. The rep had been watching his watch. The pro stopped mixing, the pro said keep mixing. this went on several times. They pro then tried it and his comment was: this stuff is amazing, really smooth, spreads nice, what did you change? The rep said, you mixed the same stuff exactly per the instructions on the bag, it's exactly the same stuff you complained about before! There's a reason they give you a timeframe and RPM for your mixing paddle, and the shape of the paddle can make a big difference, too. Some will add too much air into the mix, some won't mix it up well.

There's a learning curve on the use of anything. If you've got a quality dryset (and pretty much any manufacturer has a price leader and a premium dryset mortar), mix it well, it works. If your mix is too dry or not mixed long enough, it is stiff and doesn't spread well, and has much less initial tack. Then, it can be a pain to get it to stick or fill in. This is true for a modified, too, and maybe more so if you want all the extra properties you pay for.

The issue with a modified thinset between two impervious waterproof layers is drying. If you allow enough time without disturbing it, it will work. Since the manufactuer isn't there to babysit and enforce those restrictions, and it would be really tough on a pro job where time is of the essence, they recommend a product that will always work.
 

Chefwong

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GraniRapid I've used once in a marble setup. I consider Granirapid a special application mortar - IMO. It's a very Rapid Setting Product with great hold. A bit too rapid for me.....and it's also very expensive . 2 Part combo probably runs about $80+ here. My sales rep even agreed that it's a *special application* mortar and he's a sales guy....

Bob, I know you mentioned Versabond and alot of the folks over at JB recommend Versabond.

I'm old skool. I like buying tile products from tile shops-suppliers. Hit up your local Mapei or Laticrete store and strike a conversation....
At the end of the day, on this job or the next tile job, when you run into a bind.....and need a specialized application product, you may be going to the *tile supply* store to get the right product. Support the little box guys if you can. I try as much as I can.
 

Jadnashua

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FWIW, when Schluter products first were used by John Bridge, he liked them and the concept, but didn't trust the use of an unmodified. He chose to use Versabond, a lightly modified thinset. As he became more familiar with the stuff, his trust level improved, and he switched to a good unmodified. So, since on the internet, it is very hard to erase anything, that still shows up as an alternative. I only met him once, but he switched to a unmodified. A lot of the Schluter line has been around for 30-years, it works for those applications it was designed for as spec'ed. None of the other copies, modifications on their product have been around anywhere near that long, and some of them were specifically developed to solve certain problem installation situations. They probably work long term, and given the right circumstances, are likely a fine choice. No one product is perfect for all situations. Don't blame the car for unintended accelleration when the operator was pressing the gas instead of the brake!
 

JohnfrWhipple

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Listen to the posts above.

From an DIYer. He had a hard time using non-modified thinset. So did thousands of people for ages. This is why modified thin sets where invented.

1). Higher initial grab
2). Better expansion abilities
3). Longer working times

And on and on.

Schluter's Kerdi does not allow the use of modified thin sets. You can not use modified thinsets over Kerdi or Ditra and maintain your warranty.

Noble Seal TS does allow the use of modified or un-modified thin sets.

Spider Web does as well

Dural does does as well.

Bond breakers are the number one reason for a tile failure. Walking on tiles certainly will disturb them but often it is the packaging dust on tile that is to blame or the fine layer of dust on the sub floor.

Keep your job site clean. Sweep up and mop the area with a sponge. Don't set over drywall compound - scrape it off the floor. Wipe the backs of the tile and back butter.

When your setting tile you should be with every new mix of mortar and every so often be setting a tile and then removing it to check coverage rates. This is old school advice and standard operating procedure here in Vancouver for us. Not to beat a dead horse but if you first set Kerdi and then tile how can you do this? The lifting back up of a tile creates suction and can pull Kerdi of the wall. Case in point for why we use rapid setting mortars.

The use of a modified thinsets will make your life easier. Clean tiles and subfloors give you the best chance of a good install.

If your install fails - do you not want a warranty of some kind? I do.
 
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