How far can the floor drain be offset from the tub drain?

Ella does not publish a maximum offset figure, and the tub drain does not have to sit directly over the existing floor drain. The drain body on an Ella walk-in tub lets your plumber connect from the left, the right or the center, the T-type drains have ports that let the pipe run in either direction, and the tub can be shifted sideways so its drain is offset from the house drain, with PVC running beneath the tub to the trap. What limits the offset is your own floor and the size and run of the house drain line, which your installer measures before you order. The decision that has to come first is the door side, explained in Should My Walk-In Tub Door Be on the Left or Right Side?, because the door and the drains sit on opposite sides of the tub.

How the Tub Drain Reaches a Floor Drain That Is Not Underneath It

An Ella walk-in tub is not set down over a drain rough-in that has to line up exactly. The drain body hangs below the tub floor, and there is space under the tub for the lines that connect it. Because the drain can be connected from the left, the right or the center, and because the T-type drain has ports that let the pipe leave in either direction, the plumber picks the most direct path from the tub drain to the existing trap and runs PVC beneath the tub to get there. If the house drain sits to one side of where the tub drain lands, the tub can also be shifted sideways within the space, so its drain is offset from the house drain instead of lined up over it. Pipe direction plus tub position is what bridges the offset, and neither requires the floor drain to be moved.

There is no published figure for how far is too far, because the practical limit is set by the room rather than by the tub. The size and run of your house drain line and the clear space under the tub along the path decide what the plumber can connect, and those can only be measured in your bathroom. Have your installer measure the existing line before you order, and give your Ella dealer or the team at (800) 480-6850 the model name so they can confirm the drain position for that model. With both numbers in hand, the installer knows the distance the pipe has to cover before the tub arrives.

Why the Door Side Is the First Decision

Every Ella walk-in tub has its door on one side and its drains on the other. A right-side door puts the drains on the left, and a left-side door puts the drains on the right, with sides taken as you face the tub. Since the tub drains have to end up on the side of your house drain, the plumbing location is the first thing to settle. Stand where you will face the tub, note which side the existing drain is on, and the door goes on the opposite side. Confirm this with your installer before you place your order, because the tub is built with the door on the side you order and the hand cannot be changed afterward. Choosing the hand this way is also what keeps an offset manageable: the tub drain starts on the correct side of the tub, so the pipe runs under the tub to the existing drain over the shortest path.

Choosing the hand for the drain can put the door where there is less floor space, so check the swing clearance on that side before you commit. Inward-swing doors need no floor space in front of the tub. The outward U-shape doors on the Capri, Monaco, Front Entry, Mobile, Lounger, ShaK, Big4One, Tub4Two and Big4Two swing 165 degrees and need about 21 inches of clearance in front, and the outward L-shape door on the Transfer family swings 172 degrees and needs about 36.5 inches. How far each door family projects, and what to look at when a toilet sits on the door side, is in How Far Does the Open Door Stick Out in Front of the Tub?. If the drain side forces the door toward a toilet or a vanity, an inward-swing model keeps the drains on the correct side without needing floor space in front of the door.

Upper Floors and Finished Ceilings

On an upper floor with a finished ceiling beneath the bathroom, the aim is to leave that ceiling alone, so choose the door and drain hand that lets the pipe run under the tub to the existing drain. The combination of connecting from the left, right or center and shifting the tub sideways is what makes that possible, and it is the situation in which measuring the existing line carefully before ordering matters most, because the path under the tub is the only path available.

What to Measure Before You Order

1. Stand where you will face the tub and note which side the existing floor drain is on. That is the drain side, and the door goes on the other side.
2. Measure where the center of the existing drain sits relative to the walls the tub will stand against, so the installer can compare it with where the tub drain lands for the model you are considering.
3. Have your installer check the size and run of the house drain line and the clear space under the tub along the path the pipe will take.
4. Check the floor space in front of the door side against the swing figure for that door family, and switch to an inward-swing model if the space is tight.
5. Give the model name and your drain measurements to your Ella dealer or the team at (800) 480-6850 so the drain position for that model can be confirmed before the order is placed.

If Your Question Is About a Shower Base Instead

A shower base works differently, because the drain is molded into the base and cannot be shifted after the fact. On a custom-size Ella shower base the drain must sit at least 9 inches from the back wall and at least 9 inches from the nearest side wall, measured from the outside edge of the base, a limit that comes from the molds used to form the base. Within that limit the drain can be centered or offset, located by two measurements called C and D that the team confirms in writing before the base goes into production, and the base cannot be trimmed on site. If your existing drain line is closer than 9 inches to a wall, ask the team to review your dimensions before you order and plan with your plumber for the possibility that the connection under the floor will need to move. The details are in How Close to the Wall Can the Drain Be on a Custom Shower Base, and Can It Be Centered?.

Common Questions