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How to Remove Sewage Smells in a Home

Removing sewage smells from your home can be tough, especially if you do not know how to locate the source of the smell. However, learning how to get rid of sewage smells yourself can save you a lot of money in plumbing expenses.

It is helpful to know how the plumbing is supposed to work. You also need to know how to track down the smell and tips for removing sewage smells from your home.

Determining whether sewer gasses are harmful to people and pets

Hydrogen sulfide, a toxic gas, is responsible for the odor that sewer gas emits. However, for sewage gas to be detrimental to people or pets, it must be in a much higher concentration than that what enters your home.

Studies show that hydrogen sulfide starts affecting a human central nervous system in concentrations of150 parts per million (PPM). This is 10 percent higher than the typical gasses detectable to humans and animals. The sewage gas smells people may experience in their homes never reach such levels. The bottom line is that it is not harmful, but it is unpleasant.

Understanding how the plumbing should work

Plumbing consists of a piping system that runs throughout your home. When the plumbing is put together and maintained properly, it should not emit any odor. Plumbing is designed to bring clean water into your home and take waste water out. The pipes that carry waste water out of your home are just as important as the pipes that bring in clean water.

Each water source, such as sinks, toilets, and showers or baths, has a drain vent and traps that prevent waste water from reentering your fixtures. Once the water leaves the drain, sewer gasses should not reenter your home either.

Finding the source of the smell

Sewer gasses can only get into your home if there is a plumbing issue. The most common plumbing problem that leads to sewage odor is a drain that is missing a trap. Basement and utility drains are the most common source of smells due to missing traps. Plumbing is designed with ventilation pipes to take sewer gasses outside. Other sources of sewage smells include the following issues.

Dry traps 

When water flushes down a toilet or drains down a sink or tub, some of the water gets caught in the plumbing trap for that fixture. This trapped water acts as a seal, preventing sewer gasses from reentering your home.

However, if certain fixtures are not used regularly, the water can evaporate. This allows sewer gas to leak into your home’s atmosphere. You may need to run some water or flush the toilet in question every few weeks to prevent bad smells.

Damaged drainage pipes

If the drainage pipe is cracked or broken between the trap and the sewer line, sewer gasses can seep through the cracks.  A broken pipe can also allow sewage to drain into the basement or crawlspace underneath the house. Standing sewage under the house will also emit a foul odor. If you have a mess on your hands or the damaged pipe is hard to reach, you may need a professional plumber to take a look at it. Raw sewage can pose serious health hazards if you are not careful.

Plugged vents

Most homes have roof vents connected to the plumbing system. When you release water into the drain system, it creates suction. The vents allow the system to pull in fresh air to replace what is pushed down the drain.

Sometimes the vents get clogged with leaves or other debris. When this happens, the plumbing system still has to replace displaced air. Instead of pulling the replacement air through the vent, it pulls it through the trap of a nearby fixture. The pressure removes the water seal from the trap, allowing sewer gasses to enter your home. Make sure the rooftop vents are free of debris, then run water down the fixture with the odor.

Testing plumbing with a smoke machine

Smoke machines make artificial smoke that does not leave a lingering odor or stain surfaces. Connect the smoke machine to your plumbing then block off the sewer drain pipe and cap the roof vents. Make sure all the fixture traps contain water.

The smoke can help find holes or cracks in pipes, vents, or traps by slightly pressurizing the plumbing system. The water barriers prevent the smoke from bubbling up through the fixtures. Instead, the smoke will exit any cracks. This professional plumbing trick can significantly reduce the time it takes to find a damaged or leaking pipe.

Gathering supplies to remove sewage smells from your home

Get prepared for the task at hand by having these supplies handy

  • Wrench
  • Screwdriver
  • Water hose
  • White vinegar
  • Baking soda
  • Two gallons of hot water
  • Bleach
  • Mineral oil

Shower drain smells like sewage

If the smell is coming from a shower drain, you can clean and freshen it to remove the smell from your home. First, unscrew the trap, then dump one cup of vinegar down the drain. Next, pour in ¼ of a box of baking soda, close the bathroom door, and let the mixture sit for two hours. After that, pour a gallon of hot water (not boiling) down the drain, and let it sit for 15 minutes. Then, thoroughly rinse the vinegar out of the drain with cold water.

Next, pour a half a cup of bleach into the drain and leave it for two hours. Close the door and open a window or turn on the exhaust fan; the bleach smell can be as bad as the sewer gasses. Rinse the bleach out using another gallon of hot water. Turn on the faucet and run the water for ten minutes to flush the drain.

The final step is to dump four ounces of mineral oil into the drain. This prevents the water in the trap from evaporating as quickly. You do not need to use the mineral oil if the fixture is in frequent use. This procedure will also work for smelly bathroom or kitchen sings.

Dealing with home sewage problems

Here are a few other solutions for ridding your home of sewage smells.

Seal uncovered floor drains. Sewer smells can omit from uncovered floor drains. The drain covered by tapping a piece of plastic over the opening, and poking holes in it, allows water to drain.

Install an automatic seal trap. You can purchase automatic seal traps at many plumbing supply stores.

Purchase a self-priming trap. This trap is suitable for areas where water spills are common.

Getting rid of a sewage smell in the bathroom

If the toilet emits an odor, you may need to remove it. Make sure to turn on the water and drain the holding tank. Use a wrench to take out the bolts, then remove the toilet. Check the floor for water damage, which can cause a foul odor. If the floor is the source of the smell, replace that section of floor.

Replace a broken toilet

Inspect the toilet for signs of damage like cracks or chips. Replace the toilet if the porcelain is broken.

Check the flange placement

If the toilet flange top is below the floor surface, the seal may not be preventing sewer gas leakage. To fix a low-lying flange, unscrew it with a screwdriver. Next, attach a flange extender and screw the flange back in place. Now bolt the toilet back to the floor.

Install traps for storm drains

If your storm drains do not have traps, consider installing them. Although storm drains are different than waste water drains, it can back up your waste water system if they get clogged.

Preventing sewage smells from returning

Follow this routine checklist, to avoid sewer gas odors from reoccurring in your home.

  • Never allow a drain to go unused. Routinely run water in your sinks, showers, bathtubs, and toilets.
  • Pour mineral oil into infrequently used drains to keep the water seal from evaporating.
  • Keep your rooftop vents free of debris.

Finding and removing sewage smells from your home can be tough. However, learning how to get rid of the smells yourself can save you plumbing expenses.

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