“so what do you think is the best way towaterproof a shower or a bathtub surround?†this is a question i get a lot over on homerepair tutor. so today i wanted to make a video and show you how to waterproof a showeror a bathtub using three different methods. so this is going to be really cool. and inthe end i want to get your input on the three different methods. so stick around becauseyou’re going to like this video, and i think it’s going to bring up a lot of insightand new skills that you may not be aware of—and that’s always kind of cool. so let’s diveinto it right now. the first method to waterproof your tub iswith cement board. replacing 1†spacers on the tub deck such that the cement boardwill sit above the tub lid. and then steve,
my co-founder over at bathroom repair tutor,is marking the position of the prefabricated niche on the cement board. what he’s goingto do is cut that out. so first, what steve is going to do is makea chalk line on it for the horizontal location. then he’s going to mark the vertical locationusing 2â€x4â€s and then cut it out using an angle grinder with a tile saw blade. sothat’s how you do that. now here’s the deal: you should only beusing alkali-resistant screws when installing cement board. put them in 1†from the edgeand then 8â€-10†within the field of the cement board.so steve is dry fitting the top piece here, and again, he’s just going to cut out asection so that the cement board will fit
around the niche. so again, 8â€-10†withthe alkali-resistant screws within the field, and you should be good to go.now another way to cut cement board is with a utility knife or carbide-tipped knife witha square—so in this case a drywall square. we’re putting the piece of cement boardup on the back wall, not the plumbing wall. again it’s 1†above the tub deck. placeyour screws in place. and then we’re butting the cement board up against the drywall forthis back wall as well. so for the plumbing wall, you’ll alwayswant to have your drywall in place first. then get your measurements for the mixingvalve. transfers those to the cement board along with the tub stop measurements. andthen what you can do is make perfectly cut
holes for this. steve’s using a 1†paddlebit for this, nothing special. and then for the mixing valve, he is going to be usinga 3†hole saw. so they’ll give you perfect cuts for the holes for the tub spout and themixing valve. place your cement board 1†above the tub deck again, and then screw itinto place. you do the exact same method for the shower head hole that’s above the mixingvalve location. so again, just use a 1†paddle bit, and your â½â€ copper will fitright through there for the shower head. you want to butt the cement board up against thatdrywall. so in this case, we had to put a little pieceof cement board in place between the tub and the drywall.now you have to waterproof your cement board.
there’s no getting around this. we’reusing ardex 8+9 in this tutorial, and they use a mesh to help out with all the differenttransitions. so what we’re doing is placing green painter’s tape—use any kind of tape—toput it on the tub deck and fill in that gap between the cement board and the tub usingthe ardex 8+9. that’s going to waterproof that space. and then you’re going to putmesh over top of that. steve right now is rolling on the ardex 8+9 to waterproof allof the cement board. again, you have to do this in order to ensure your cement boardisn’t going to leak water through it. so as you can see, steve is using the ardex 8+9mesh here. we’re using that in lieu of alkali-resistant tape because that’s what the ardex 8+9 directionscall for. you can also use hydro ban, red
guard, etc., but you have to waterproof cementboard. it’s a must. and when you’re done waterproofing, pull the painter’s tape upfrom the tub deck. the second method is schluter kerdi board.you want to make sure that your walls are nice and plumb and level. what we like aboutkerdi board is it’s light. and again, you want to mount it right above the tub lip usingtheir screws and washers. the nice thing about kerdi board, besides it being light, is it’seasy to cut. so you can score it with a utility knife; it’ll cut easily. you can trim itthat way. so they have specific instructions on howto install it. you want to put a screw and a washer in every 12â€. and your stud shouldbe 16†on center at a minimum for a â½â€
board. but follow the schluter instructionsand you should be good to go. so again, the nice thing is you can scoreout the area where you want to put your niche. then you can install your niche, trace aroundit, cut around it with a utility knife, and then you can install the niche in that location.that’s what steve is doing here. he’s picture-framing that schluter kerdi boardand then placing the niche within the stud bay.so anyhow, you can pinch the niche to the kerdi board using the screws and the washers.it’s very simple to do. anybody who knows how to use an impact driver or drill can dothis. so the kerdi board’s easy to use. i’m pretty sure any diyer can install it.so again, you just score it with a utility
knife. actually, it’s easier than drywall.steve is cutting the last board that we’re putting in place here between the ceilingand the first kerdi board. so again, you can just scribe cut it, no problem.we make it flush with the ceiling. so nice flush cut, install it using the screws andthe washers, and you should be good to go. just super simple to use. and the nice thingabout it is it has gridlines on it, so you can cut it easily.so here’s the back wall. very similar to cement board. you just put it in place. youwant to cut everything to size. and steve is actually cutting out a hole for the tubspout using a utility knife. he places the board on the wall, and boom, he’s goingto hit it there, puncture it to mark the location
of the mixing valve. and then he’s goingto cut out the mixing valve using that same 3†hole saw. so, super simple. anybody cando it. so again, you just put everything in place. put a little piece of kerdi board betweenthe tub and the adjacent drywall. now what we did is mix up some unmodifiedthinset. so unmodified thinset, pancake batter consistency—you’re going to put this inthe space between the tub and the kerdi board. now this is steve’s preferred method. kerdidoesn’t recommend this, but this is what steve likes to do. and then you can put thekerdi band over top of that. so you embed the kerdi band into the unmodified thinsetusing a 6†drywall knife. you do the bottom positioning first with the kerdi band.what we’re explaining here is instead of
using the unmodified thinset, you can actuallyfill in that gap between the kerdi band and the tub using kerdi-fix. so you put kerdi-fixin that gap. then you put unmodified thinset on the kerdi board and embed your kerdi bands.so that’s the schluter-preferred method for waterproofing between the kerdi boardand the tub. so if you want their warranty to be upheld, you follow their directions.so in this case, what we’re doing is we’re applying unmodified thinset to the corner.then we’re overlapping the kerdi band over top the bottom band that we just put in place,again just using the 6†drywall knife. so kerdi board’s really, really easy toinstall. i can’t emphasize that enough. you want to put the kerdi band wherever twokerdi boards meet, wherever the niche is embedded
into the wall—so you want to put the kerdiband there. and then you put the unmodified thinset any screw and washers and put a littlestrip of kerdi band over top of those. that way when you smooth those out, you’re goingto waterproof all the screws and the washers. and a little nice tip here is to kind of smooththat out using a damp sponge. and that will give you a nice, solid surface for your tileto be adhered to. so the transition between the kerdi boardand the drywall, again you just use kerdi band. you want to smooth out or take off anyof the thinset that is left on the drywall. the third and final method for waterproofinga shower or a tub is to use wedi building panels. now we like these a lot because they’reeasy to install like kerdi board, and you
use screws and washers just like you do forkerdi board. now wedi makes their own screws and washers, and we recommend that you buythose because they’re obviously manufactured for wedi building panels. and they have theirown specifications on how far you should be installing the screws and the washers fromthe floor and within the field. you always want to apply the wedi joint sealant on topof adjacent boards, and embed one board on top of the other board, and sandwich it togetherusing that wedi sealant. now wedi is easy to cut, too, so steve justused a paddle bit to cut that hole in it. and what you do is you can pinch the washersand the screws in between the two boards. you can do this, too, with schluter kerdiboard. and then you smooth out the joint sealant—we’re
going to touch that further a little bit lateron in the video. but you want to smooth out that joint sealant.you can cut the wedi building panel with an oscillating multi-tool or a utility knife.you can build out your own niche using it. all you need is the wedi sealant, the wedibuilding panel, and the screws and the washers to build a custom niche. it’s really thatsimple. and it’s cool for older homes that have really weird dimensions.so again, you can cut out your hole for the mixing valve using a hole saw. and then youwant to apply wedi joint sealant on any joints and any washers and screw holes, and thatwill waterproof the wedi building panel. it’s that simple. it’s actually even simplerthan the schluter kerdi board. but each method
has its own pros and cons. so again, we addedanother layer of the joint sealant on all of the transitions between wedi building panels.that’s what you want to do. that’s what steve is doing here for the custom niche.we built this walk-in shower in only four hours using the wedi building panel. and ifyou wait two hours, you can actually start tiling over top of it.so those are three different methods for how to waterproof a shower or a bathtub. i hopethat you like this video. lots of really great new concepts in it. so down in the commentshere on youtube or back on over at homerepairtutor.com, let me know which one method you would usein your bathroom if you were to remodel it. i think it’s really cool to open up thisdiscussion because in the comments i typically
end up answering a lot of questions. so thatis it for today. oh, the other one thing i wanted to let youknow about is this: steve and i came up with a free bathroom remodeling video series foryou. so this is great because it’s going to help you remodel your bathroom faster,easier, and cheaper by showing you different skills, like the ones we went over today.you can check that out right here. so just click right here, it’ll take you over tothe sign up form, and you’ll get that instantly today.so that pretty much is it. that wraps up the video for this week. remember a new one comesout every single tuesday at 8 am, so you can count on a new video every single week, andi don’t want you to miss out on that. you
can always subscribe by clicking the subscribebutton here. all right, i’ll see you down in the comments.have a great day. thanks for watching. talk to you soon.i accidentally hit this button which sprays this shower head. it went all over me whilei’m shooting the video. funny stuff. that’s what happens when you try to make youtubevideos in the shower.