An Ella shower base is installed in one fixed order: dry fit it in the framed pocket with no adhesive, level it until the bubble is centered, mark the front point of the threshold on the subfloor, set the 2 inch drain, bed the base on beads of 100 percent silicone, check level a second time, and only then screw the flange to the studs. The slope that carries water to the drain is molded into the base, so the base itself has to sit level for that slope to work. Ella films this sequence for its low threshold and barrier free bases, as described in Are there videos showing how to set an Ella shower base and walls?, and this page explains what to check at each step and why the order matters.
Before the Base Arrives in the Room
The installation videos pick up at a framed, open pocket. Everything before that point is site work for the local licensed contractor or plumber: removing the existing shower, stall or tub, clearing the pocket back to the framing, and preparing the floor and the plumbing so the base lands on the rough-in. Frame to the specification drawing for your exact model rather than to the nominal size in the shower's name. The drawing gives the exact opening and depth to frame and the distance from the back wall and the side wall to the drain center, and Ella Shower Rough Opening, Standing Area and Floor Width walks through reading it.
- Check the pocket for square, plumb and level before the base goes in. A sloping floor makes the base rock, and out-of-plumb studs push the top of a wall panel away from the base once the walls go on.
- If the alcove is wider than the unit, fur the walls out before installation. Do not shift the base sideways to close the gap.
- The drain opening is molded into the base in a set position for each model and cannot be moved to the other side. Treat the drawing as the starting point and the dry fit as the final word, because framing variations and wall thickness can shift the base slightly.
- Keep any wall panels flat, indoors and at room temperature until installation day.
The Installation Sequence, Step by Step
- Dry fit the base. Set it in the framing pocket with no adhesive so you can see how it sits and where the drain lands. For a three-piece shower, dry fit the complete unit, base and walls together, on a flat, level floor before anything is fastened. That dry fit becomes your reference: if the alignment pins and holes line up outside the alcove, the panels are good, and any misalignment inside the alcove comes from the room.
- Level the base. Adjust until the bubble is centered, checking front to back and side to side. A base that rocks or slopes defeats the molded slope and, later, throws every alignment pin out of line.
- Mark the threshold. Mark the front point of the threshold on the subfloor. The base is lifted out for the drain work and the adhesive, and this mark is where it returns to.
- Locate and set the drain. With the base in the pocket, mark the drain center through the base opening. Only then cut and set the drain pipe. Set the 2 inch drain body with plumber's putty.
- Bed the base. Lay beads of 100 percent silicone and set the base back on its marks.
- Check level again. A base that was level during the dry fit can shift when it is bedded. This is the last point at which it is easy to correct.
- Screw the flange to the studs. Once the flange is fastened the base is no longer easy to move, which is why the second level check comes before this step and not after it.
- Install the wall panels, or the glue-up tile flange if the walls will be tiled.
Watch the whole video before the first bead of silicone goes down. Each step builds on the one before it, and the two level checks are there on purpose.
Why There Is No Mortar Bed Under an Ella Acrylic Base
Many shower pans need a mortar bed mixed and screeded under them before they are set. Ella's standard and custom acrylic bases do not. They are vacuum molded from an acrylic capped ABS sheet and reinforced underneath with high density foam bonded to the shell, which is what lets them sit directly on a level subfloor or concrete floor. The barrier-free roll-in bases are a different construction, fiberglass with the AcrylX finish, and are listed as pre-sloped, reinforced, self-supporting and pre-leveled. Both constructions are explained in Are Ella acrylic shower pans reinforced, and how much weight do they hold?. The practical point for leveling is that the floor under the base is what you level against, so a flat subfloor matters more than it would with a bedded pan.
The cultured marble bases are heavier than acrylic and need at least two people to install, so arrange the help before the dry fit rather than during it. Whatever the material, the base is the finished walking surface as shipped, with its slope, threshold and drain molded in. Tile, thinset or a membrane should never go on top of it, as Can You Tile Over an Ella Acrylic Shower Base? explains, and a tiled look belongs on the walls above the base.
Finishing the Wall Joint
A separate Ella video covers the glue-up tile flange, and its main lesson is where to mark the strip position on the walls so the wall finish meets the base correctly. The flange is what lets the wall surface come down over the edge of the base so water runs back into the pan rather than behind it. If your plan is tile or another wall finish instead of Ella wall panels, ask your Ella dealer or the team at (800) 480-6850 for that video alongside the base video, and confirm the joint detail with your tile installer before work begins.
What a Leveling Mistake Looks Like Later
A base that is not level, or an alcove that is not plumb, usually shows up when the wall panels will not line up with the base. The pins and holes that matched in the dry fit are suddenly out of reach, or a panel will not sit flat. Before assuming a part is faulty, have your installer confirm that the base is level front to back and side to side, that the alcove walls are plumb and square, that nothing on the wall keeps a panel from sitting flat, and that the alignment pins are present and straight. My Shower Wall Panels Do Not Fit the Installed Base. What Can Be Done? lists the photos and details the warranty department needs if the unit cannot be corrected on site. Ella does not send technicians, so these checks are done by you or your installer, and any review starts with photos sent through ellasbubbles.com/support.
Related Guides
- Do you have installation instructions for an acrylic shower base and wall surround?
- Does an Ella Shower Base Need a Mortar Bed to Keep Its Warranty?