Why Your Bathtub Faucet Leaks When Your Shower Is On & What To Do About It

Imagine this: You’re standing in your bathroom, ready to enjoy a relaxing shower before or after your day. But instead of water flowing only from the showerhead, you notice your tub spout leaking when the shower is on. Annoying, right? Not only can this waste water, but it might also lead to more serious plumbing issues down the road. If you’re dealing with a tub faucet that leaks when the shower is on, there are a few common causes behind this frustrating issue — fortunately, there are also solutions. In this blog, our expert plumbers at Dean’s Home Services cover these causes and the solutions.

Causes & Solutions for a Leaking Bathtub Faucet

A bathtub faucet that leaks while the shower is running is a sign that something’s not working as it should. Let’s go over some common reasons that this problem occurs:

Hard Water Buildup

If you live in Minneapolis or St. Paul, you might already be familiar with the effects of hard water. Over time, minerals in hard water, like calcium and magnesium, can build up inside your faucet and shower components. This buildup can prevent parts like the shower diverter or the faucet valve from sealing properly, leading to your shower spigot leaking when it should be off.

To tackle mineral buildup in your bathtub faucet, you can clean or replace the affected parts. Vinegar or a descaling solution can help dissolve mineral deposits. However, if the buildup is significant, it’s best to replace your faucet or showerhead entirely.

Faulty Shower Diverter

The shower diverter is the valve that switches water flow from the bathtub faucet to the showerhead. If the diverter is old, damaged, or stuck, it might not fully close, which can lead to a tub spout leaking when the shower is on.

You can try cleaning the diverter valve to see if mineral deposits are causing it to malfunction. If cleaning doesn’t solve the problem, the diverter valve may need to be replaced. Many homeowners can handle this job with a bit of DIY effort, but if you’re unsure, hiring a plumber from Dean’s can ensure the job is done right.

Worn-Out Parts

Inside your tub faucet, there are several small parts that help create a watertight seal. Over time, washers, gaskets, and cartridges can wear out or degrade, causing water to leak through the bathtub spout even when the diverter is supposed to redirect water to the showerhead. This is especially common in homes with older plumbing.

Replacing a worn-out washer or gasket is a relatively simple DIY job for many homeowners. However, if the problem is with the cartridge — a key component that controls water flow—it’s a bit more complex. A professional plumber can quickly identify the issue and replace any worn-out parts, saving you time and hassle.

Faulty Plumbing Installation

If your shower’s plumbing was installed incorrectly, it could cause pressure imbalances that result in a tub faucet dripping when the shower is on. Poor installation can also lead to ongoing wear and tear on your plumbing system, making it more prone to leaks.

Fixing an improper plumbing installation is not a DIY-friendly job. A professional plumber will need to assess the situation and possibly rework the installation to correct the pressure issues.

Call Dean’s for Expert Plumbing Services

A leaking bathtub faucet may seem harmless, but it could turn into a bigger issue if unaddressed. Getting professional help is the best way to prevent water waste and avoid damage to your home. Dean’s Home Services has provided outrageously professional service to the Twin Cities since 1996, and our team of experts is ready to tackle any plumbing problem you’re facing. We pride ourselves on offering same-day service and upfront pricing, so you’ll never be left in the dark about repairs. Call our friendly team today and get your shower back in working order!

Contact Dean’s for expert plumbing repair in Minneapolis, St. Paul, and the surrounding areas.