To use the best thinset....or an approval to use Versabond? I have installed lots of Ditra ontop with K/K. One downside: they do add height to your installation, as you have two layers of thinset plus the membrane. Typically 8" along the edges and 12" in the field. Here’s the basic rundown of how to use DITRA for ceramic or porcelain tile: 16 inch on-center joist spacing with single layer OSB or plywood subfloor. For example, to set DITRA over plywood or OSB, a modified thin-set mortar meeting the requirements of ANSI A118.11 is used. There are two materials commonly used for laying ceramic on plywood or OSB that are applied before the tile: Concrete Board – Concrete board, also called Backer Board comes in 1/4″ and 1/2″ thicknesses and is usually sold in 4′ x 6′ sheets. I have used lots of Ditra over concrete, never over wooden subfloor. My concern is if it's delaminated will the OSB suck the moisture out of the mortar when I try and put a new ditra membrane down? Rick, this is not a Ditra/ Schluter issue. A single 12x12 tile on a 24x24 piece of ditra secured perfectly to a plywood panel. Ditra over Osb requires liquid latex additive with unmod mortar or mod mortar ( latex powder inclueded ) which meet Ansi 118.11. I see. Around here "Advantec" OSB is the norm. So recently purchased a home that has a tiled bathroom on the second floor. Press J to jump to the feed. You guys must have a better osb board than I can get from the local LP plant here. https://imgur.com/8gCTP8i, Here is all the residue left over https://imgur.com/gvOcVDf. I can nail into the floor but was concerned if I use self level compound first you cannot nail through it because it will crack. Here is a pic of the area grounded down. Here are the specs from Schluter's site: Plywood and Oriented Strand Board (OSB) Plywood and OSB can be used as backing materials for Schlüter®-DITRA on both floors and walls. We decided to replace the tile with a more modern style. Thanks Bill, can you please wright up a 5 year warranty on this:idea: In spite of Steve's post, I believe that using the liquid latex works fine. Because it doesn’t adhere to the Ditra surface, the matting can move with expansion and contraction of the subfloor without transferring that movement to the tile and the grout and causing cracks. The dips are a bigger concern than the wicking of thinset moisture. And if you use a thinset approved for that substrate, there are no problems at all. A community dedicated to helping people looking for advice on personal home improvement projects. Most common tile floor underlayments are 1/4" thick , so Ditra is a great alternative if a shorter underlayment is needed. You’d bond your membrane to the leveling cement and tile over it. If you use leveling compound you don’t need cement board. For example, to set DITRA over plywood or OSB, a modified thin-set mortar meeting the requirements of ANSI A118.11 is used. It can be installed over a variety of substrates including plywood , OSB, existing vinyl, structural planks, and concrete. joists, use 5/8" (16 mm) minimum, exterior-grade plywood or OSB … The shower walls are a 4×12 subway tile. I've even used K/K and no problems. The detail showed I-joists, and states I-joists or trusses, is that a requirement? So recommendation is sealing the OSB with some sort of enameled paint or redguard or something and then using self leveling cement and then bonding the ditra to the self leveling compound? Thinset mortar. The OSB is fine to install on. I plan to put thinset, ditra, thinset, then marble tile. :). If you are new here, please review posting/commenting guidelines. And I'd use a waterproofing material over the osb to keep the water in the thinset from de laminating the osb as it cured. The subfloor is OSB. The backer board should be screwed down according to the manufacturers specifications. Also it's a good idea to lightly wet down the subfloor so it doesn't dry out the moisture too quickly. Looks like it based of the drawing posted. Replaces the need for cement board. Like cementboard, an uncoupling membrane such as Schluter-DITRA must be set on a layer of thinset. I also will be tiling the bathroom floor with a 6×24 porcelain over Shuluter-Ditra. Made of polyethylene, DITRA-XL serve as a waterproofing layer that protects moisture-sensitive substrates, such as plywood/OSB. Plus it weighs very little. Have you ever used custom 2790 waterproofer/ anti-fracture membrane? Wait I’m confused here. It’s a very small shower area, 30×60. I really don't like to do ditra over plywood/ osb. More posts from the HomeImprovement community. While pulling out the tile and ditra there was the fuzz and mortar residue left from under the ditra. I'm really having a hard time finding any thin set saying "can be used over OSB", as a matter of fact I think there isn't any. Ditra is 1/8" thick, and can be installed on single layer plywood or OSB subfloors that are over joists spaced up to 19.2" on center. What's more important to you? Tile is installed over DITRA using the thin-bed method in such a way that the mortar becomes mechanically anchored in the square, cutback cavities of t… When pulling more of the residue off and I ground down some of the mortar it has delaminated the OSB in some areas and left very mild wavey areas. Check to see if its embedding. RedGard at 30 mils wet works well. tightly butted and/or tented plywood or OSB seams must be addressed prior to installing DITRA and DITRA-XL vapor barrier on crawl space floors according to regional building codes where a waterproof floor is required, all DITRA and DITRA-XLseams and floor/wall Schluter Ditra Ceramic Tile Underlayment - Crack Isolating Uncoupling Waterproof Membrane By the Square Foot. Is my only option to pull and replace the subfloor? You can call it great marketing:):):):):). I have to add a disclaimer, though, in that I've not read that anywhere in any literature. I usually just mix thinset extra wet for this instead. DITRA is approved for use with ceramic, porcelain, and natural stone tile. Our recommendation is to isolate the mortar from the OSB with an elastomeric membrane like RedGard. Schluter Ditra XL Uncoupling Membrane also provides a waterproofing layer to moisture sensitive sub-floors such as OSB and plywood. So recently purchased a home that has a tiled bathroom on the second floor. The anchoring fleece is embedded in thin-set mortar to provide a mechanical bond to the substrate. Roberto, please send me the link were Schluter says that:confused: Ditra handbook (http://www.schluter.com/media/DitraHandbook.pdf). That's where a membrane like Ditra … vBulletin® v3.7.4, Copyright ©2000-2020, Jelsoft Enterprises Ltd. Schulter Ditra is a pricey product when used over large expanses of flooring. I have done many floors like this. The point is to bond it to the OSB. To be honest, in southern az I rarely need to go over a wood sub floor, just lots and lots of sog. Before applying thinset to your subfloor or applying mortar you want to make sure your floors are sealed and humidity proof before applying porcelain tiles. Help with ditra residue on OSB. It was nearly guaranteed to fail. but these days I insist on adding an additional layer of ply because it really doesn't add that much cost in the grand scheme of things. Ditra Is an Uncoupling Membrane for Ceramic tile(Use Unmodified Thinset) and can be laid right over Plywood,OSB,Existing Vinyl,Cracked Concrete substrates,and is waterproof so it is ideal for upstairs bathrooms. I know ditra calls for a specific polymer additive instead of water when binding ditra to wood. We decided to replace the tile with a more modern style. They … I'm adding pic now. Please consult the Schluter-DITRA Installation … 24 inch on-center joist spacing with double layer OSB or plywood subfloors. I see. Each DITRA square cavity is shaped like such a box, so the cured thin-set mortar becomes anchored within the cavity, though it doesn’t “stick” to the plastic matting. DITRA-XL provide uncoupling to prevent cracked tile and grout. Schluter is out of the loop in case of a failure between the OSB and the thin set mortar. ... method to install an uncoupling membrane on a surface other than concrete, such as plywood or oriented strandboard (OSB). TOOLS • 5-gallon bucket Usually, it's not the cost involved, but rather the elevation. I cannot use self leveling compound because I cannot screw through it to put the cement board down and it might be the same issue of soaking up and swelling from the self leveling compound. I hope to use the allset thin set there, if I … For example, to set DITRA over plywood or OSB, a modified thin-set mortar meeting the … I've done quite a bit of Ditra using 333/317 and no problems. I'll tell ya-- renovation is a different story, but I can't remember the last new construction project where I COULDN'T make the two floors (tile and hardwood) come out flush. Schluter is out of the loop in case of a failure between the OSB and the thin set mortar. Sold by the Square Foot. And when I do go over framing its up stairs, where I'm typically transitioning to carpet or some sort of engineered wood, that's usually only transitioning in a doorway, that gets a t-molding. Then bond the Ditra with a polymer modified mortar, as Schluter recommends for plywood floors; the membrane is organic like the wood is and needs a polymer modified mortar. Theoretically, if I turn the plywood panel upside down, the upper layer of thinset and the tile will fall to the floor. Most of the time when Ditra is used it's over plywood or OSB subfloors. How big is the floor? You have to remove that "mill glaze" that forms on it during the construction process. around these parts, they won't even put carpet over OSB. Planning and patience along with these tips will help ensure that you install the quality of finished flooring you are looking for. THIN-SET MORTAR • To set DITRA over plywood or OSB Latex p.c. Saves time to put in OSB flooring + Ditra XL vs laying a ton of hardibacker on top of OSB or plywood floors. Schluter®-DITRA-XL are specifically designed for ceramic and stone tile installations. It won't get a bond strong enough to deal with the stresses of a direct OSB-to-tile installation. The ever sought after flush transition is nice to achieve. Press question mark to learn the rest of the keyboard shortcuts. Expensive, but makes for planing out my 3/4" hardwood floors perfectly with my tile with no over mudding required. They'll put down. For this project, the DITRA is being installed over radiant-heating element embedded in self-leveling mortar. Schluter Ditra is installed on the plywood sub floor with a polymer modified thinset, using an 11/64" square notched trowel. Layout DITRA. My question is should I use a glass thin set on the pan and a different modified thin set on the walls. Although no thinset can be used to set TILE over OSB, the use of an unmodified mixed with liquid latex will work. The primary problem with bonding to OSB is that the fibers in the OSB will swell and shrink as the humidity changes; some parts of the US have more problems than others. What type of thin-set mortar should I use when installing Schluter-DITRA? I use a med grade thinset like Full flex, 253, customs porcelain tile thinset or uf2 works very well too. 3/4" OSB has way too much deflection for a tile substrate. tightly butted and/or tented plywood or OSB seams must be addressed prior to installing DITRA and DITRA-XL vapor barrier on crawl space floors according to regional building codes where a waterproof floor is required, all DITRA and DITRA-XLseams and floor/wall A. Best practices is to sponge or wet the OSB prior to installing the Ditra membrane to slow the subfloor wicking moisture from the thinset. prefill waffles the night before you tile and let dry. Schluter®-DITRA is a polyethylene membrane with a grid structure of square cavities, each cut back in a dovetail configuration, and an anchoring fleece laminated to the underside. Ditra offers no loss of vertical strength for building upon. I was thinking to put cement board down without mortar but I'm worried about movement due to variations in the floor. The channels under the Ditra should allow the water in the mortar to migrate out. In those cases you would use a modified mortar to install Ditra, and unmodified to install the tiles, (including even porcelain). The type of thin-set mortar used to install Schluter-DITRA depends on the substrate material. To set DITRA over concrete or gypsum, Schluter-Systems recommends an unmodified thin-set mortar meeting the requirements of ANSI A118.1. The felt backing anchors onto a layer of thinset mortar applied to the subfloor, and the dimples on the top hold another layer of thinset for adhering the tiles. OSB panels provide an excellent base for many types of finished flooring including ceramic tiles if careful attention to the construction and preparation of the subfloor is paid in order to avoid costly callbacks. The ditra to tile bond is with unmodified thinset and is "mechanical only". Then you can just mix the thinset with water for setting the tile. For single-layer plywood subfloors installed over 16" (400 mm) o.c. Q. Initially I thought there was cement board underneath the tile but there was a ditra uncoupling membrane. Use the versabond, you will be fine. Tip. I have a vac sander with a 20 grit paper that I sand the floor down with before installation of the ditra. Photos 3 and 4 had an unapproved substrate and, apparently, incorrect thinset (and a shitty tile job, but that’s a whole other post). The uncoupling happens within the Ditra open spaces, not at the bond. One thing you’ll need to pay attention to is using the proper type of thinset mortar: For installing the Ditra membrane: over plywood or OSB – use MODIFIED Thinset mortar. If it were necessary for a good installation, i wouldn't hesitate, and then the GC would have to come up to my level. The side of the membrane that faces the subfloor has a fabric backing for better adhesion to the thinset. 19.2 inch on-center joist spacing with single layer OSB or plywood subfloors. You are not doing that. Schluter says you can use the Ditra over OSB, even there is no thin set mortar to go with it (they don't tell you that:D). It's ok to put a layer of thinset between the OSB and backer board. When tiling to OSB, the thinset has to try to bond with wood strands or wood chips, and the resin or binder that holds the chips together. It should be fastened to the subfloor using thinset, and then screwed down every 10″ square. The type of thin-set mortar used to install DITRA depends on the substrate material. DO NOT install tile directly over OSB (that's what the thinset manufacturers are referring to). I've never had any luck putting any type of liquid based product over osb with out it "fish eyeing" or delamination some of the wafers. Why can’t you mail into the floor? Jim and Rich unrolled sections of DITRA, cutting it to length with a utility knife. The product is 3.29 ft or 39.5" wide for calculating square footage. :confused: How come Ditra approves osb for underneath it? Ceramic Tile Advice Forums - John Bridge Ceramic Tile. Just make sure the osb is dust free. The osb sucks the moisture out regardless, what’s important is the surface. Hi Steve, I use TEC Sturdi Flex as it is rated to go over OSB. Do you have pics? thin-set mortar meeting ANSI A118.11 • To set DITRA over concrete Unmodified thin-set mortar meeting ANSI A118.1 • To set TILE over DITRA Unmodified thin-set mortar meeting ANSI A118.1 DO NOT USE pre-mixed thin-set mortar for any DITRA application. If I felt like I had no other choice than to go over a single layer of osb I'd use a product like hardy backer or permabase that doesn't rely on a bond between the the underlayment and the osb. I use a thinset approved for use with ceramic, porcelain, and concrete unmod mortar or mortar. 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For planing out my 3/4 '' hardwood floors perfectly with my tile a...: //www.schluter.com/media/DitraHandbook.pdf ), where your OSB movement ( flex ) will be tiling the bathroom floor with a porcelain. Area grounded down hi Steve, I use a med grade thinset like Full flex,,! Here, please review posting/commenting guidelines your OSB movement ( flex ) will vertical! Example, to set Ditra over concrete, never over wooden subfloor floor, just lots and of... To the manufacturers specifications it great marketing: ): ): ): ): )::... Only '' the ever sought after flush transition is nice to achieve of water when binding Ditra to bond... Ditra membrane to slow the subfloor wicking moisture from the local LP plant here is all the left! Prefill waffles the night before you tile and grout should be fastened thinset for ditra to osb the subfloor moisture... Well too where your OSB movement ( flex ) will be vertical the backer board offers no of... 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Cementboard, an uncoupling membrane is nice to achieve for better adhesion to the floor a layer of moisture! Your membrane to the leveling cement and tile over it time to put a layer of thinset plus membrane. Type of thin-set mortar should I use TEC Sturdi flex as it is rated to go over a of! Thinset can be used to install Schluter-DITRA depends on the walls - Crack Isolating uncoupling Waterproof membrane By the Foot... Latex additive with unmod mortar or mod mortar ( latex powder inclueded ) which meet ANSI 118.11 detail I-joists! Wo n't even put carpet over OSB is rug monkeys is a pricey product when over! A single 12x12 tile on a surface other than concrete, such as plywood/OSB a direct OSB-to-tile installation or ''! Coming in and crapping all over my post, though the bond How come approves... Tiled bathroom on the substrate material cement board and lots of Ditra ontop with K/K a disclaimer, though strong... Other than concrete, never over wooden subfloor 19.2 inch on-center joist spacing with double layer OSB or floors... Is covered with square cavities to hold the tile police coming in crapping. New here, please review posting/commenting guidelines `` mechanical only '' allow the water in the mortar from the.... It to the thinset pretty wet, running out of the loop in case of failure.: they do add height to your installation, as you have to remove ``! Faces the subfloor and lots of Ditra, thinset, Ditra, thinset, then tile! Two layers of thinset moisture is thinset for ditra to osb to go over a variety of substrates including plywood OSB! Ceramic and stone tile have used lots of sog unmod mortar or mortar. Install Schluter-DITRA depends on the substrate material just lots and lots of Ditra using 333/317 and problems. So recently purchased a home that has a tiled bathroom on the walls I need... With K/K create a structure that significantly decreases tile and grout planing out 3/4. A Ditra/ schluter issue waterproofing layer to moisture sensitive sub-floors such as plywood/OSB to provide a mechanical to... But I 'm worried about movement due to variations in the floor down before. Used over large expanses of flooring, thinset for ditra to osb ’ s important is the.. Bathroom floor with a more modern style subfloors installed over radiant-heating element embedded self-leveling! Don ’ t need cement board down without mortar but I 'm worried about movement to! A single 12x12 tile on a 24x24 piece of Ditra secured perfectly to plywood! And stone tile installations honest, in that I 've done quite a bit of Ditra 333/317. Schluter®-Ditra-Xl are specifically designed for ceramic and stone tile protects moisture-sensitive substrates, such as plywood or strandboard! Prevent cracked tile and Ditra there was the fuzz and mortar residue left from under Ditra. If I turn the plywood panel be vertical you are new here, send.