But a mortar bed does have advantages. By clicking Post Your Answer, you agree to our terms of service, privacy policy and cookie policy. Sloped Shower Tray KST1220/1525 - The Home Depot. Though, each product comes with its own individual characteristics, and pros and cons. @JimmyFix-it - You are right. When installing Schluter Kerdi Membrane over cement backerboard: Should I use Alkali Resistant Mesh Tape and thinset on the seams of the backer board (for long term durability to prevent each board moving independently thus preventing cracking) prior to installing the Kerdi membrane. Should I redo this wall to avoid a mold sandwich? We store towels, medicine, toiletry supplies, first-aid gear, massage devices, facial steamers, spare Painting your garage is a great way to improve the look of the space and make the walls easier to clean. Politique d'Utilisation des Cookies de Houzz. Needless to say, the drywall turned to mush. This flexible polyethylene layer is easy to install and can protect the tile from both cracking and moisture. It costs more but it;s worth it for the ease of install IMO. Preparing drywall for KERDI membrane requires a few important steps to ensure a successful application. Cement board and grout are not water proof, if there's Kerdi no moisture is ever going to be able to get behind it. We ended up sponging the Hardi and wetting and booking the Kerdi (a la wallpaper), and that made the installation go much smoother. In general, modified thin-set mortar is not recommended to set ceramic and stone tile, including large format tiles, over the KERDI membrane. Step 7: Cut the Tile. But that doesn't address your question, so it's just a comment, not an answer as such. The most important thing to remember when applying the membrane over the cement board is to make sure the surface is clean and free of any debris, dust or other contaminants. Bulk update symbol size units from mm to map units in rule-based symbology. We mixed the thinset, it wasn't as smooth as the utube video, but it was close, and we gave it ten minutes. When I tried to use the edge of my trowel [per schlutter video] I could see I was pulling a lot of the 'felt' off the backer. We also found that using a heavy rolling pin worked wonders for really setting the Kerdi. Like the example above. The foam core surrounded by synthetic cloth on both sides and adhered with resin glue is. Why does the plumbing rough need to be moved? The use of modified thinset adhesive could result in an inadequate bond and could lead to possible delamination. Why do small African island nations perform better than African continental nations, considering democracy and human development? I used to "trust" the Kerdi and drywall until I had a shower that the valve broke inside the wall cavity four years after being put in. To create a watertight shower assembly, we installed Schluter's Kerdi membrane over the drywall, just as we would for tile.Write by:. Learn about the options in exterior siding before you choose, Before you pick up a single tile, pull from these tips for expert results, Slip resistance, curves and even the mineral content of your water all affect which tile is best for your shower, We help a Houzz user ask all the right questions for designing a stylish, practical and safe shower bench, This isn't a light DIY project: You'll need heavy-duty tools and plenty of protection for your home and yourself, In steamy quarters, tile needs to stand up to all that water and vapor in style. The waterproof membrane isn't a substitute for the substrate. Spacers are the next step. To subscribe to this RSS feed, copy and paste this URL into your RSS reader. Then cement, sand and water are mixed together to a crumbly consistency and floated over the lath to form a flat surface. True cement board (Durck, Wonderboard) is my first choice as a tile or Kerdi backer. Manufactured by Schluter Systems, Kerdi Board is a multifunctional tile underlayment and construction panel, that can also be implemented for forming bonded waterproof assemblies with tile coverings. I want to mount a cast iron bathtub, but not pull down my 1905 plaster and lath. To ensure that the Kerdi is completely dry prior to tiling, inspect the inside of the membrane for any signs of moisture or condensation. The completed assembly takes the place of more traditional backer board when installed over 3/4-inch wood subfloors. Schluter SET, ALL-SET, FAST-SET or an unmodified thin-set mortar must be used to construct all KERDI seams to ensure watertightperformance of the system. The main types of cement board you could encounter are Fibre Reinforced Cement (FRC) board and gypsum board. I have used kerdi, and I have applied it over cement board. This is necessary to ensure that the membrane will adhere properly to the drywall. Kerdi really offers very little advantage over hardiboard plus membrane. I also used a larger sized trowel than the one recommend by Schluter. When applying thin-set mortar, the manufacturers instructions should be followed closely. If your going to do the job do it right, and give professional advice pls. But there are downsides. I trust it and have never had a callback. Other mistakes I was making early on:-over working the thinset. Installing cement board involves placing the boards atop a layer of thinset adhesive, a process known as bedding. craft paper or plastic is great if the inspector wants it but it is (should be) doing nothing for a tub surround that has HB/redgard/thinset/tile. What precautions should I take installing tile on a backerboard in an area surrounded by cement? No, you do not need to install a vapor barrier, as Kerdi Board is the vapor barrier. When cleaning thinset off of Schluter membranes, the manufacturer recommends using a wet sponge and taking care to avoid any scoring or inconsistencies on the surface of the membrane. It is a fast process that is hard to mess up if you do it right. An additional layer of sealant can also be applied on the seams for extra protection and water resistance. Additionally, if the cement board isnt waterproof, it can also cause mold and mildew issues, as well as dry wall damage from the moisture seeping through. Need help liner vs liquid membrane question. Yes, it is recommended to waterproof cement board, especially if it is going to be used in exterior settings or in places where it will be in contact with water. Answer (1 of 3): Schluter recommends applying Kerdi over drywall for walls, however, my local building code will not permit this practice - the local building code requires cement backer on the walls of a shower enclosure, therefore, I have done this successfully many times. I used 1/2 Hardibacker board over the studs and then used the Kerdi membrane over the Hardi. I hang Kerdi on cement board and fibercement board all the time. True cement board (Durck, Wonderboard) is my first choice as a tile or Kerdi backer. Hi David. My idea is to block in and install the tub in the existing corner, erect the new wet wall, and use hardi-backer to shim the wall out over the tub flange, then apply kerdi over the whole thing.Does kerdi take offense at being installed over hardi? Learn more about Stack Overflow the company, and our products. Furthermore, if you're working in an older home KERDI-BOARD fits better than cement board in odd spaces. I think the first one I used was cheap and that was part of the problem. Run a damp towel over the cement board surface to dust . We use a pump action garden sprayer and its usually dry by the time we clean the sprayer. I like to use a garden sprayer to keep the thirsty Kerdi wet. link to What Kind Of Paint For Garage Walls? Depending on your project and the specific cement board you are using, you will want to select a thinset appropriate for both.if(typeof ez_ad_units!='undefined'){ez_ad_units.push([[468,60],'remodelormove_com-large-leaderboard-2','ezslot_15',158,'0','0'])};__ez_fad_position('div-gpt-ad-remodelormove_com-large-leaderboard-2-0'); The two primary criteria to help guide your selection are the type of cement board you are using and whether you are installing it indoors or outdoors. First Kerdi can be installed on drywall or cement board. This is a bit difficult to answer as it depends on the particular application for the floor system. To line niche shelves, for instance. Will use the Schluter Shower system. Recovering from a blunder I made while emailing a professor, Minimising the environmental effects of my dyson brain. There are many different types of underlayment to choose from, but they all serve the same purpose. Plus, if you use the mold and moisture resistant drywall, it will be extra insurance against mold. So long as the seams and joint areas are properly prepared, the panels can also provide waterproofing. Connect and share knowledge within a single location that is structured and easy to search. Following the instructions for the product being used and ensuring that all of the necessary steps are followed will help to ensure a successful installation. I guess that why it was so frustrating that cement board is just sooo thirsty. Fiber cement board is available in 1/4-inch and 1/2-inch thicknesses. The benefit of using kerdi is we can lay it over drywall, We've added a "Necessary cookies only" option to the cookie consent popup. Hang the cement boar. 120 sq feet including the floor. Both Kerdi Board and cement board are designed to smooth out uneven spots on the installation surface, create an unbending layer that wont flex underfoot, and also provide a waterproof barrier. if(typeof ez_ad_units!='undefined'){ez_ad_units.push([[580,400],'remodelormove_com-leader-2','ezslot_21',165,'0','0'])};__ez_fad_position('div-gpt-ad-remodelormove_com-leader-2-0');Once the seams are sealed, lay down a waterproof coating to the floor and walls of the shower space. Stack Exchange network consists of 181 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers. Once this is done, continue the installation by following the directions for the particular Kerdi product being used. Additionally, a liquid water-resistant membrane should be applied over all surface areas before installation. Important to overlap seams in a shingle method. 120 sq feet including the floor. Once the primer is completely dry, use a roller or brush to apply a coat of your chosen KERDI membrane adhesive over the entire surface of the wall, overlapping the edges slightly for full coverage. As a contractor, I have been using Kerdi since it came out. RedGard, on the other hand, is a liquid waterproofing membrane made by Custom Building Products. This will help to ensure that all drywall is completely covered. I simply sponge off the excess. The colour is different. This is often accomplished by filling any holes and cracks in the wall with appropriate spackling or patching material. I appreciate your help and your quick response. Problem with very thick cement board/ tile/bullnose edge, Steam Shower Slip Joint Detail - The secret is in the boarding stage. The problem is on the back side of the drywall, which is not protected. The thin-set mortar should be mixed to a fairly dry consistency and then spread on the surface with a 1/4 inch square notch trowel. Browse other questions tagged, Start here for a quick overview of the site, Detailed answers to any questions you might have, Discuss the workings and policies of this site. I posted a plea for help and Mongo and Bill both gave me good advice. Will add it in. It could take longer if the space is particularly wet or humid. Too little, and the kerdi will never show you gray, no matter how you sweat. And for a more secure fit, you can also use screws. Waterproofing is an important aspect of any bathroom or wet-area installation. It installs with screws, then you tape the joints & screw holes and install your tile. The product involves an extruded polystyrene foam panel, with specialized reinforcement materials on both sides. #2. x 33 ft. Waterproofing Membrane: Kerdi-Board 1/2 in. When it comes to applying KERDI, however, it is advised to use a regular thinset that includes portland cement as its main component. FRC board tends to be more moisture-resistant than gypsum board and is best suited for outdoor projects such as showers or tub surrounds. The 1/4-inch-thick board is typically used on floors and countertops. Cross your fingers and hope it's all OK. Not the best Kerdi Showcase. Hello D Zak!