What is a shower pan and what does it actually do?

A shower pan is the molded floor of a shower: the tray you stand on that catches the water, slopes it to the drain and keeps it from running out into the room. Ella's Bubbles calls the same part a shower base, and shoppers also search for it as a shower receptor. Ella makes its pans in finished acrylic with the slope, threshold and drain molded in, in three standard sizes and in custom rectangles, as listed in What Sizes Do Ella Shower Bases and Shower Pans Come In?. This page explains what the pan does, what each part of it is for, and what that means for planning your bathroom.

The Four Jobs of a Shower Pan

1. It is the floor. An Ella pan is a finished acrylic surface, the walking surface as shipped. Once it is set it is ready to use, with no tile, thinset or waterproofing membrane on top.
2. It moves water to the drain. The slope is molded into the pan, so water runs toward the drain opening on its own instead of pooling on the floor.
3. It keeps water in the stall. The threshold, the raised edge at the entry, is molded in as well. On a curb-less roll-in pan there is no threshold, so a self-adhesive collapsible rubber dam ships with the base to hold water in while a wheelchair rolls over it.
4. It ties into the plumbing. The drain sits in a set position for each standard size. Your contractor sets the base, connects that drain to the house waste line and finishes the walls around it.

The pan also gives the walls something to land on. The base meets the walls along its edges, and whatever wall finish you choose comes down over that edge so water runs onto the pan rather than behind it.

Why the Pan Is a Finished Surface, Not a Substrate

In a tiled shower the word pan often means a rough waterproof tray that tile is laid over. An Ella pan is the opposite. It is the finished floor, and it is not made for tiling over. Tile needs a rigid, absorbent substrate that mortar can bond to. Acrylic is smooth and does not accept thinset, so tile laid over it would not bond reliably and could trap water underneath with no path to the drain. Tiling would also bury the molded slope and threshold the pan relies on to move water. The shell is made solid by being supported from underneath, which is the correct way to make the base feel firm, rather than by adding a layer on top. Can You Tile Over an Ella Acrylic Shower Base? goes through this in detail, and the answer is to choose a different base rather than cover one. A tiled look belongs on the walls above the pan.

Ella also offers cultured marble shower bases in three sizes. These are molded solid bases with a glossy gelcoat finish and a slip-resistant textured floor. They are heavy and take at least two people to install, so plan the delivery path and the crew before the base arrives.

Threshold Styles and What Each One Means

• Curb-less roll-in. The three standard sizes are ADA curb-less roll-in pans with no threshold to step or roll over. This is the pan for anyone bathing from a wheelchair, and it is why the collapsible dam ships with it.
• 3 inch step-in. A step-in threshold base is offered for those who prefer a slightly raised edge that holds water at the entry.
• Custom threshold. A custom shower base typically has a threshold of about 3 inches, placed on the longer side of the rectangle.
• Zero threshold. Zero threshold bases sit flush with the surrounding floor for a barrier-free entry.

Your Ella dealer or the team at (800) 480-6850 can confirm which threshold style suits your bathroom and how it meets your plumbing rough-in.

Sizes and Drain Positions

The three standard pans share a 60 inch length and differ only in width: 30, 32 or 36 inches. Each comes with a left or right drain, and left-hand and center-drain bases are among those the team has supplied, so tell the team where your existing drain line sits in the floor and it confirms which drain position matches your size. A standard pan is the simplest choice when one fits, because the drain is already where it needs to be.

When a standard size will not fit, a rectangular pan is made to order. The custom minimum is 30 by 30 inches, the largest is 44 inches wide by 80 inches long, and corner bases top out at 42 by 60 inches. The drain can be placed left, right or center but must sit at least 9 inches from each wall, so a drain only 7 inches from the threshold edge is not possible, even on a custom pan. Only rectangles are made, and angled or curved edges are not offered. What sizes do shower pans come in, from smallest to largest? lists the footprints that have been built, and Who makes custom shower pans for odd bathroom layouts? explains which awkward rooms a rectangle can and cannot solve. Custom bases are made for three-wall alcoves and for corner installations, and the team asks which layout you have so the drain and edges are placed correctly.

What the Installer Checks Before Setting the Pan

The video on this page walks through the start of a low-threshold three-piece shower installation, and its preparation steps show what a pan needs from the room. First the unit is dry assembled in a clean, dry, open space before anything moves into the bathroom, to confirm the correct panels arrived, the drain is in the correct location, the pan and panels are free from damage, and the pieces align. Take a picture of the assembled unit, and hold off on demolishing the existing tub until you are sure the new unit is the correct size and condition. Then the framing pocket is checked against the dimensions on the framing diagrams page of the installation instructions and checked for square, plumb and level, and adjustments are more common than not. A plumb bob hung from the back wall framing shows whether the wall is plumb, and if it is not, the fix is to shim the pan away from the wall or notch the stud. The subfloor is inspected before the pan goes down. Slight variances show up later as walls out of plumb and uneven lines, so the time spent here is what makes the pan sit right.

Ella pans are sold on their own, per item, so a complete shower is the pan in your size and drain position, a wall system sized to it, and any accessories. Contractors who expect to buy regularly can apply for the dealer program, and Who Makes Custom Shower Pans and Bases for Accessible Showers? explains where each piece is carried.

Watch: Step-by-Step Low-Threshold Shower Installation for Remodeling | Ella’s Bubbles with chapters and a full transcript.

Related Guides

• How Do I Measure for a New or Replacement Shower Pan or Base?
• What Are the Standard Shower Base Sizes Ella's Bubbles Offers?
• What the Ella Acrylic Shower Base Is Made Of and How It Is Installed

Common Questions