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Bathtub Drain Not Lining Up [2 Easy Fixes]

You’re installing a new bathtub in your washroom.

After installation, you notice that the drain is not lining up.

The new drain is not in the same place as the existing drain. This must be worrying you. 

What to do when your bathtub drain isn’t lining up?

There are mainly two ways to fix this issue. The first is, fitting a coupler or an adapter at an angle. The second option is redoing the fittings underneath the base of the tub. Then using wood shims to level the floor. If you’re hesitant, call a plumber and ask him to help you.

This is just a summary of the solutions. We’ve gone into detail in our article below. 

Interested in knowing the whole process? Just scroll down!

Why Doesn’t My Bathroom Drain Line Up?

There are very few reasons why this can happen. The most common cause is that you live in an ancient house. The drain line of old homes and modern houses don’t match. 

Modern tubs are also built to match the drain line for modern houses. The drains don’t line up when you change the old bathtub and install a new one.

Another time this can happen is when you change the whole system. Like, you were using bathtubs before, and now you’ve installed a shower. Or, you were using a shower before, and now you’ve installed a bathtub. 

Bathtubs and shower tubs don’t usually have the exact drain line location. When you change systems, it can be problematic to line up the drain lines. And when drain lines don’t align, low-profile shower trays can overflow.

There’s another reason, but the chance of this happening is infrequent. It’s the movement of fittings under the tub. It can be caused by decay, or it can occur when they contract excessive force.

The movement of fittings below the tubs can cause the drain lines to shift. It can sometimes cause the tubs to change slightly in a random direction. And that could cause the drain line to fall out of line.

This is about all the possibilities. Now, let’s fix this issue.

How To Fix Bathtub Drain Not Lining Up: 2 Ways

There are mainly two ways to fix a bathtub drain not lining up. The first process is straightforward and not time-consuming at all. It’ll probably take you a few minutes to get it done.

But the other process is a lengthy one. It’ll require a lot of work to get it fixed. Since it’s a long process, we’ll cover it in a different section. It’ll be easier for you to understand that way. Just so you know, Americast Princeton tubs have other problems.

Without further ado, let’s get into the solutions.

Method 1 of 2: Installing A Coupler or An Adapter

This is a straightforward method. But you can’t utilize this method if the drains are more than an inch apart. You can only use a coupler if they’re apart by an inch.

All you need is a coupler or an adapter for this method. The size of the coupler depends on the size of your drain. If it’s a 1.5-inch drain hole, then get a 1.5-inch coupler. The length of the coupler needs to match that of the drain line.

You can change a 2-inch to a 1.5-inch shower drain if you want a smaller one. They’re more convenient, after all.

Now, you have to place the coupler at an angle. This will allow the water to flow directly inside the drain. Take off the drain cover and insert the coupler. Place it at an angle, and all the water will go straight down the drain.

Now you know how to install a coupler or an adapter on a bathtub drain. Let’s not waste any more time and get to the other method.

Here are a couple of couplers for you to look into:

Flex-Drain 55020 Drain Pipe CouplerCheck Latest Price
Flexible Rubber PVC CouplerCheck Latest Price

Method 2: Changing The Fittings Underneath The Bathtub

This method is viable only when the first method fails. When it fails, we mean when the drains are more than an inch apart. Then you should use this method. Before this method, choose a drain gasket or putty for your tub.

You can go about two ways regarding changing the fittings. The first is that you can apply floor leveling compounds around the area. Spread it around a foot from the opening on the tub, and you’ll be good to go.

Here’s a list of some of the best floor leveling compounds you can use:

Custom BLDG Floor Leveling CompoundCheck Current Price
SAVOGRAN Floor Leveling CompoundCheck Current Price

The other method requires you to have cut cement boards. They’re sold in sheets just like drywall in the market. This use of a cut cement board will help you level the area. You’ll even be able to seal the area under the frame to avoid any leaks.

Lower the tub base onto the frame and check if the drain lines line up. If they don’t, take some wood or plastic shims and use them to balance the base. Screw these shims directly to the floor. 

Next, install new rubber seal gaskets for the drain. Caulk the joints at the base with silicone caulk. And finally, if you have any other plumbing connections to make, do them, and you’ll be done.

This is everything on changing the fittings. It’s a pretty easy job, so you should be able to do it yourself.


Should my tub drain have standing water?

If you have standing water, unclog the bathroom as soon as possible. They can give rise to diseases.

Can I pour boiling water into the drain?

No, you definitely shouldn’t do it at all. Boiling water can harm PVC pipes. There are different pipes for running hot water. And drain pipes aren’t like them.

Do bathtubs come with an overflow system in them?

Yes, they do. It is to keep the bathtub water from overflowing. They’re usually located just a few inches below the rim.


After reading this article, you should be able to fix the bathroom drain not lining up.

We hope you’ll follow our instructions properly.

Call a licensed plumber to your rescue if you get stuck or face any issues. 

Good Luck!