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Why Is My Floor Drain Backing Up?

Posted on: April 22, 2022

Rubber duckies floating on standing water in a flooded basement laundry room.

Floor drain backups can be baffling. When they happen, it can be easy to assume that there’s a problem with the floor drain itself — but that’s not the case at all. In fact, backups in a basement floor drain are usually a symptom of another problem in your plumbing system.

So, if you’ve noticed standing water in your basement or you’re experiencing floor drain backups, here’s what you need to know about what’s causing them and how to fix them.

Clogged Drain Lines & Floor Drain Backups

Clogs in any of your home’s drain lines can cause backups in your basement floor drain. That’s because, as the lowest drain in your home, the floor drain will be the first place that wastewater can go when it can’t flow to the main drain and sewer line. So, with the main drain backing up, wastewater will continue to build up in the line until it overflows and backs up out of the floor drain.

For homes that don’t have a basement floor drain, drain line clogs can cause backups in the lowest fixtures of the home, like ground-level tubs, sinks, or showers.

Sewer Line Clogs

Floor drains can also back up when clogs lie deeper in a home’s plumbing system, like somewhere in the sewer line. Similar to drain line clogs, sewer line clogs will stop the flow of wastewater. With nowhere to go, wastewater will back up until it finds the nearest release point, which will be a floor drain or the lowest drain in a home.

Sewer Line Damage

Sometimes, clogs have nothing to do with floor drain backups. That can happen when:

  • A sewer line has cracks or holes.
  • A sewer line is bellied, sagging, or collapsed.
  • Tree roots have misaligned or infiltrated the sewer line.

In all of these cases, the sewer line will have a blockage that acts like a clog in that it forces wastewater to back up into a home. Unlike a clog, however, sewer line damage can require far more work to fix.

How To Stop Basement Floor Drain Backups

Since various issues can cause floor drain backups, stopping the backup starts with knowing precisely what’s causing it. And that requires a professional plumber. Some of the things a professional will do to identify the problem and the proper repair include:

  • Asking you questions: A plumber will ask how long the problem has been going on, whether it’s happened before, whether the backup has a foul odor, and whether it gets worse when you’re using plumbing fixtures. The answers to these questions can help narrow down whether you’re dealing with a drain line or sewer line problem.
  • Testing your plumbing fixtures: Turning different fixtures on and off can give a plumber firsthand information about how your system is acting (or acting up) as water flows through the drain and sewer line system.
  • Performing camera pipe inspections: This lets a plumber see exactly what’s going on within the lines, what the problem is, and precisely where it lies.

After this diagnostic process, a plumber will be armed with the information necessary to recommend the most appropriate repairs. Depending on the findings, the best repairs to stop basement floor drain backups could include:

How To Prevent Future Basement Floor Drain Backups

Following repair service, the best way to avoid future backups in your floor drain is with regular drain cleaning maintenance service. If your sewer lines are in good shape, routine drain cleaning service will keep your lines clear, free of the buildups that can clog and stop up your system.

While that can save you the headaches and mess of backups, it can also save you a lot of money in the long run, helping you avoid the need for repairs or emergency plumbing service.

Schedule Drain & Sewer Line Service Now

Whether you’re dealing with floor drain backups or any other plumbing problem, Len The Plumber is the team you can always rely on for customer-focused service and first-class plumbing solutions!

Call Len The Plumber at 800-950-4619 or contact us online to schedule service now!

We know that plumbing problems can’t wait — whether they happen during or outside of standard business hours. That’s why we’re proud to always offer 24-hour emergency plumbing service at no extra charge and a two-hour response time for all drain and sewer emergencies! Plus, we always provide FREE estimates, upfront pricing, and exceptional service!

That’s why there’s no better choice for a plumbing company in Maryland, Northern Virginia, Pennsylvania, Delaware, and Washington, D.C. — and why our customers love us!

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