What causes the smell in my shower drain?

There are several common reasons for smelling shower drains. Listed below are the most likely reasons why your drain smells like mildew or sulfur. You should have no trouble finding and removing the virus after following these tips. 

Strainer or stopper clogged

Most showers come with a strainer or stopper built into or over their drains. Hair, soap scum, and other debris are caught by these fixtures before they flow down the drain. Your strainer or stopper may accumulate gunk and grime over time. Typically, odors in shower drains are caused by old, accumulated debris and shower runoff caught by your strainer or stopper.

Your stopper can probably be removed by hand. Using a small screwdriver, remove the screw on strainers. As soon as you pull out the strainer, you’ll likely notice hair, grease, and scum. You can clean the strainer with a sponge, a bristle brush, or an old toothbrush if you wear some gloves. You should also remove any scum left on the drainpipe where the strainer was removed.

Mildew or mold growth

Dark, moist places are perfect for mold and mildew to flourish. Anywhere in your shower where it has a chance to grow, it will. Make sure your strainer/stopper is seated correctly when you remove it. Check the seal on the drain cover itself as well while you’re at it. Mold and mildew flourish in any spaces between the drain cover and tub or the strainer and tub.

Using a mold and mildew removal solution, remove the drain cover and stopper. As well as the underside and ring around the drain, be sure to spray them down and clean them. Ensure that your cover fits snugly over your drain once you’re done. You need to replace it immediately if it won’t sit properly and is warped.

Dry p-trap


Your p-trap may not be working if you smell sewer gases or rotten eggs. Look down the drain with a flashlight. If there is no water in the trap, there could be a problem. Let two cups of water flow through your drain for an hour. Pour four ounces of cooking oil down the drain along with the water if that doesn’t work. If it doesn’t work, the cooking oil may prevent the water from evaporating.

Blocked or clogged vents

Your shower’s vents may be blocked if you’re trying to introduce water into your p-trap but it keeps disappearing. The venting of pipes allows air to escape when water is introduced. Without it, water could continually leak out of your trap due to suction inside your pipes. All pipes have a vent that connects to the vent stack. Vents are connected to your traps and eventually to an outlet called a “vent stack.”

Clogs in vent stacks are most common. Perhaps a bird’s nest was near its entrance, or perhaps debris fell into the vent. You might be able to clear it yourself if you know where the vent stack’s outlet is. To begin, remove anything that is in the vent’s mouth. If you cannot locate anything, the problem may be deeper inside and you can contact Epsom Plumbing Services. Try turning the stack’s outlet on and running a hose down it. The water pressure should aid in clearing up the vent system.


Paul watson