How to Diagnose a Bathtub Leak

Source: Laurel Kate Sittig, Flickr.com

It’s just when you’re drifting off to sleep that you hear the drip, drip, drip that starts driving you up the wall. Or you find a puddle on the floor every time you come out of the shower, and you know that water can’t be leaking over the side of the bathtub – you just put those little plastic dams in last week. It’s clear that there’s a leak, but where is it coming from? You’ll have to do some tests in order to find the source. Here are some tips for getting started.

The Water Lines

If the leak is constant whether you’re using the tub or not, then the hot or cold water line is the source.

The Drain

Take a good look at the bathtub drain. Climb into your bathtub and stand over it, too. Does it feel solid under your feet or is there some give? Test your drain by running the bucket test – plug the drain and fill a bucket with water from another source. Fill the bathtub – yes, it will take time and effort – and let the water sit for about a half hour. (You can also run some rubber tubing from another faucet and fill the bathtub that way.) If you see a leak when you do this, the drain is the culprit.

If you don’t see a leak yet, there’s still one more test for the drain. Pull the plug, let the water drain and watch what happens. If water appears outside the bathtub, it’s likely that the leak is in the drain piping.

The Shower Head

Once you’ve ruled out the drain, move on to the shower head. Pull the metal ring around the shower head – it’s called the escutcheon – and run the shower while looking at the pipes with a flashlight. Watch for a leak. If you don’t find one, do the toilet paper test. Wrap some toilet paper around a screwdriver and insert it into the opening where the shower head pipe emerges. Hold it under the pipe for a few moments, and then check the paper to see if it is wet. If it is, you’ve found the leak.

The Tub Spout

It’s complicated to check for a leak at the tub spout because it may be necessary to cut into the drywall. If you’ve ruled out all other possibilities, you’ll need to check this one – but with professional help. Call a plumber before you go any further.

What to Do?

Let’s say that you’ve found the source of the leak. What now? If it’s a simple repair and you have the knowledge, experience and proper tools to do it, then go for it. If you don’t, this is no time for pride. Put down the toolbox, pick up the phone and call in a pro. Every plumber from Cleveland to Kalamazoo has a story of how a job that should have taken only a few hours mushroomed into a major project, with a bill to match, when the homeowner tried to fix it first. In addition to repairing the original problem, the homeowner ended up having to get an electrician, a flooring contractor, a drywall specialist.... You get the idea. Be smart and get it done right – for less, and with a lot less hassle – the first time.

Rahel Jaskow is a home improvement writer, covering topics from pest control to frugal DIY.