Basement tub/shower combos can be a real challenge. So in this video, we’re going to walk you through all the different steps that we took to build one. Lots of really great tips, so let’s dive in.
The first step for us was to determine how unlevel this bathroom floor was. So we placed a 4-ft level on the floor, we screwed holes into the concrete, and then we added Tapcons to indicate just how high we needed to add our self-leveler.
So you can see it was quite about 1 ½” on one end. And then we used a silicone sealant to go around the perimeter. And we actually boxed off the plumbing in this basement bathroom. So we added some of the sealant along all of the framing on the floor so that when we self-level the floor, that won’t go underneath the framing.
So we used a ShopVac to clean up any of the dust that’s on the floor; it’s really important. Then you wipe that down with a damp sponge. And then the next step after that is to actually add a perimeter foam to all of the framing.
And this is going to give you an 1/8” expansion and contraction joint along the perimeter of the entire bathroom. So again, just staple that to the studs. And then you want to prime the concrete using the primer that goes along with your self-leveler.
So in this case, we used Laticrete’s PRIME-N-BOND. We actually let that set up for 24 hours. Then we mixed up NXT Leveler. And as you can see here, that screw head, the leveler needs to come up to it.
So we had to mix about 7 bags of NXT to get this bathroom floor nice, flat, and level. So again, we just used our little squeegee here to get the floor looking good. And then we let that set up for 24 hours.
Once the self-leveler sets up, you can add a mortar base for your bathtub if the directions call for that. In this case, we’re using a Kohler acrylic bathtub. The directions said to use a mortar base.
We ensured the tub was level and the predrilled holes in the tub lip where all the studs are located. This is important because you don’t want the tub lip to crack. And then we used stainless steel or galvanized screws to secure the tub.
Our mixing valve was by Moen, and Moen requires a sold, metal tub spout. So we just soldered together some copper pipe using Mapp gas. And then we wrenched that into the bottom of our Moen mixing valve and connected the supply lines using Pex piping here.
And then we actually used Pex for the shower head as well. And now we secured this and centered it on the tub. For this tub surround, after we got the Moen mixing valve in, what we did next was waterproof the walls using HYDRO BAN Board.
So we applied HYDRO BAN sealant to the tub here, and then we actually added the board down over the tub lip. And on this main wall, we were able to do that because we actually added shims to the wall with ¼” plywood.
So as you can see here, we made a custom shower niche using the HYDRO BAN Board, which is really cool. And then on the plumbing wall and the wall opposite that, we actually filled the gap between the board and the tub using the same HYDRO BAN sealant.
So this is a really great way to waterproof a tub or a shower surround. Very quick. Easy to do. And that sealant comes in handy where the board meets up with the drywall transition. We always get questions about that, so you can do the same method.
After waterproofing the shower walls, we used HYDRO BAN liquid waterproofing membrane on the floor. And you got to use a gauge to make sure that you get the right thickness of HYDRO BAN over top your floor.
So there’s a first coat, and we rolled that on with a 3/8” roller. We let that dry. And then we actually used our paintbrush to go around the perimeter. And then applied the HYDRO BAN in the opposite direction for the second coat.
So the first coat takes a few hours to set up, then you can just immediately roll on the second coat. Once the HYDRO BAN set up, we back buttered all of our 12” x 36” porcelain tiles, and we used directional troweling over top the floor to set those titles.
These are really, really big tiles for a small basement bathroom, so used T-lock to also get them nice and level. Now we have our self-leveler down, but it never hurts to use a tile-leveling system with these 12” x 36” tiles.
So once all these tiles are set, we cleaned out all the joints and prep for the next day. After the floor set out, we did all of our prepping and planning for the shower and the tile layout. We started with the first row, and then we worked our way up to the bottom of the shower niche.
Now that first row has to be super level because everything is affected by that. And then we used a Schluter metal profile at the bottom of the shower niche. We just put that behind all of our subway tile.
Then we back buttered the sill plate tile and set that such that it was even the slope downward toward the bathtub. Now in this case, we’re using a 2×2 porcelain mosaic. We’re just lightly tapping it into the thinset mortar on the wall.
By the way, we ended up using the Montolit MasterPiuma to cut all those tile. This is a great tool for any tile setting, really. But it made it super easy. And then we cleaned out all those joints using a paintbrush and a sponge on the shower niche.
So once we got that done, the next step was to set the tile on the plumbing wall and the wall opposite that. So we just use an angle grinder and a diamond blade here to cut out a half-moon shape for the mixing valve.
So that’s a great tool if you need to do the exact same thing. So we continued up this wall, and we actually put our 4×12 subway tile into the shower niche. So to make it look symmetric on the plumbing wall and the wall opposite that, we just continued our pattern.
And we back buttered all these tiles. This is a tile that’s going to go on the top of the shower niche. So we back troweled that to have more thinset so that it wouldn’t fall off the top of the shower niche.
And then we capped that section again using our Schluter metal profile, in this case a RONDEC piece. And then we continued to tile up this main shower wall and to the ceiling. Now we left an expansion and contraction joint there at the top of 1/8” to 1/16”.
And we did that for all of the walls. So you can see, that’s how we tiled this shower. The next day, we wiped down the 2×2 tiles in the shower niche just to make sure they’re clean. And then we mixed up our grout and grouted that with a mocha color.
Now, the cool thing about this grouting process is that we used Permacolour Select by Laticrete, and you can add color packets to the grout base. So this grout base in that bag is a gray color. We just added our mocha color packet and we grouted the floor in mocha and the shower niche in mocha.
But then we used the same grout base with a bright white color packet to grout our shower walls. And this actually saved us time and money. So definitely check out Permacolour Select. We let the grout on the floor set up overnight, and then we added our vanity here.
And what we did is we made sure that the vanity is level first; it’s super important. And then what we did is we found the studs in the wall. So we marked the position of the studs. We just used two galvanized screws to secure the vanity to the wall.
And then we applied a silicone sealant along the perimeter of the top of the vanity. So again, you want to do this because you’re going to seal the sink top to the vanity. And then once that was secured in place, we added all of our plumbing on the bottom.
So we connect our supply lines and our P-Trap. It’s important to have the closet flange be above the tile floor. So in this case, we added the closet flange. We need to drill hole through that and into the concrete and through the tile and add Tapcons to secure the closet flange.
It’s really important, again, to do that. And then we added our wax ring on top of the closet flange and positioned our closet flange bolts such that they were the right distance from the drywall. And then we just compressed our toilet over top of the wax ring and then secured it to the floor.
This Moen mixing valve came with a trim kit; it’s a brass trim kit. You want to attach the tub to the copper. You have your escutcheon that goes over top of the mixing valve and the handle. Now you can adjust this handle and the temperature, so make sure you do that.
Hot tip here: just use a screwdriver; put that into the shower arm to position that shower arm where you want it. And then you can add Teflon tape to the threads of the shower arm. So about 6 to 7 revolutions should do.
Then you can hand-tighten the shower head. And then use either a crescent wrench or some pliers. Just be careful of the pliers when you tighten down on the shower head. You don’t want to scratch that.
And just test everything to make sure that the plumbing works and you have good pressure. This is what the finish showed looks like. We’re really happy with the results and hope it gives you good ideas.
If you want more detailed tips on how to build a basement tub/shower combo, our online course on phenomenal. It’s not available over on bathroom repair tutor. You can click right here. We’ll also put a link down in the description.
So if you’re doing this kind of project, that course is perfect for you. Thanks for watching today’s video. If you have any questions, add them down in the comments. We’re more than happy to help you out.