Dealing with a smelly drain is a common household problem that can be embarrassing. The stink in a drain often results from buildup of organic matter, which causes odors and contributes to clogs. Fortunately, there are several simple methods you can use to naturally deodorize your drains and keep them flowing freely. Below, we’ll explore these effective methods and tips to prevent odors from occurring in the first place.
Causes of Smelly Drains
Drains can develop odors from a buildup of organic matter like grease, soap scum, and body oils, which coats the inside of the drainpipe and collects hair or food particles. This accumulation of organic matter creates a slimy layer of microorganisms known as biofilm, which can cause odors and contribute to clogs.
As biofilm grows thicker, it becomes more difficult to dissolve, which can lead to persistent odors and slow drainage. So, it’s important to clean smelly drains promptly to remove the organic matter and biofilm before they worsen.
Before You Begin
Safety first. The substances in a smelly drain are full of bacteria and fungi, so wear gloves and protective eyewear when deodorizing your drain.
Do not mix chemicals. If you have already used a chemical drain cleaner, do not use a different type of cleaner without thoroughly rinsing the drain first. Mixing different cleaners can cause dangerous fumes or even an explosion.
Plug double-sided sinks. If the drain is in a double sink, you must block one side with a plug or cloth while you clean the drain, then switch sides and repeat.
Methods to Deodorize Sink Drains
A quick fix for minor odors
You can deodorize most smelly drains with a simple homemade drain cleaner using 1/4 cup baking soda poured into the drain, followed by a squirt of liquid dish soap. Then run the hot water faucet for 2 full minutes to flush the pipe. The soap and hot water will dissolve light biofilm while the baking soda eliminates odors.
Boiling water flush
To clean a smelly drain using boiling water, bring a pot of water to a boil and remove it from the burner. Stir in 2 tablespoons of a degreasing liquid dish soap. Carefully pour half of the mixture down the drain and wait five minutes for it to dissolve any oily buildup. Then, pour in the rest of the mixture to flush the line and remove the odor.
Hot vinegar is an effective solution for dissolving biofilm and eliminating bacteria causing drain odors. To use this method, boil 4 cups of white vinegar on the stove. Pour half of the vinegar down the drain slowly, and wait two minutes for the heat to dissolve the biofilm. Pour the rest of the vinegar into the drain and wait for two more minutes before flushing the line with cold water. This method is especially useful for cleaning bathroom sink drains which tend to collect soap scum and body oils.
Baking soda and vinegar
To clean a smelly drain with baking soda and vinegar, start by priming it with hot water for two minutes to soften any buildup. Next, turn off the water and pour 1 cup of baking soda (bicarbonate) down the drain, immediately followed by 1 cup of white vinegar. Cover the drain with a plug or cloth to keep the fizzing within the drain for 30 minutes. After 30 minutes, carefully pour boiling water down the drain to flush it.
Use a plastic drain snake
To use a plastic drain snake, remove the drain plug or stopper and slowly feed the snake down the drain. Holding the tool by the handle, turn it slowly, which will cause the short, tough bristles on the snake to collect hair, gunk, and other debris coating the inside of your drain. After several turns, slowly pull the snake straight up out of the drain so you don’t dislodge the collected grime. Once you’ve removed the snake, run hot water down the drain for several minutes to flush the line. If someone in your home has long hair, repeat this every 2 months to prevent odors and keep your drains flowing well.
Deodorizing Drains with Garbage Disposals
If you notice a foul odor coming from your kitchen sink drain only when the dishwasher runs, it’s because the two share a common drain. In this case, buildup in your garbage disposal can be the cause of the unpleasant smell. To remedy the situation, try cleaning your garbage disposal with one of the following methods.
Run ice cubes through it
To clean your garbage disposal with ice, push a few ice cubes past the rubber flange into your disposer. With the cold water tap going full blast, turn on your disposal and let the blades break up the ice for one minute. Finally, turn off the disposer and the cold water, and run hot water for a minute to flush the drain and remove odors.
Grind citrus peels
To clean and deodorize garbage disposals with citrus slices, run the hot water tap for two full minutes to loosen grime. Turn off the tap and push a couple of thin slices of lemon or orange peel into your disposal. Turn the cold water on full blast and start your garbage disposal. Let the blades grind the citrus completely for a couple of minutes, then turn off the disposal and the cold water. Finally, flush the drain by running the hot water for a full minute.
Cleaning Smelly Washing Machine Drains
If you notice a sewer odor coming from your laundry room, there’s probably greasy buildup in the drain line behind your washer. This is also an excellent step to perform after you deep-clean your washing machine. Here’s how to deodorize a smelly washer drain:
- Use a pencil to mark where the drain hose enters the box, so you know how far to reinsert it.
- Remove the hose and put a funnel in the drain box opening.
- Combine 1 gallon of warm water and 1 quart of white vinegar in a pitcher. Slowly pour this into the funnel.
- Flush the drain by pouring 1 gallon of cold water down the funnel.
- Remove the funnel and reinsert the line, stopping when you reach the mark you made.
Tips to Prevent Drain Odors
Dispose of grease and oils properly. Let grease and fats cool after cooking, then scrape them into a container and dispose of them in the trash. To dispose of large amounts of grease, like oil from a deep-fryer, use a solidifier powder.
Use drain screens to keep hair and debris from entering the drain. Placed over the drain, these screens catch hair and food particles so they don’t wind up in your plumbing system. They are easy to install and remove. For shower drains, look for screens that fit into the drain and are level with the floor.
Keep P-traps from drying out. P-traps should hold a little water at all times to act as a barrier to sewer gasses. When the P-trap goes dry, those sewer gases enter your home. Run the water in seldom-used sinks once a week to ensure the trap is full.
Clean your drains seasonally. Cleaning and deodorizing your drains is part of ongoing home maintenance. Use the quick cleaning method described above every three months to keep your drains flowing freely and free of odors.
When to Call the Professionals
You may need to contact a plumber if home remedies don’t remove the drain smell. Persistent sulfuric odors may indicate a problem with your water heater or water supply caused by hydrogen sulfide gas. A moldy or musty odor coming from the drain can signal poor ventilation or a blocked vent stack on the roof. A professional plumber or drain cleaning company can fix both and remedy your smelly drain problem.