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Why Does My Crawl Space Smell Like a Sewer? (And What to Do About It)

Why Does My Crawl Space Smell Like a Sewer? (And What to Do About It)

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A foul sewer-like odor emanating from your crawl space can be very uncomfortable.

Just imagine the nasty smell filling the atmosphere of your home. Worse is that no amount of air freshener can eradicate the odor.

So why does my crawl space smell like a sewer and how do I deal with it?

Causes of Sewer-Like Smell in Your Crawl Space

A sewage-like odor can be present regardless if you’ve encapsulated your crawl space or not.

The build-up of moisture provides an ideal breeding ground for bacteria and fungi that may emit a bad odor.

Fungi growth due to increased humidity usually gives off a strong musty odor. This is one way to tell that the sewage-like smell from your crawl space is not due to molds.

Clogged Sewer Line

The major reason could be a clogged or damaged main sewer. This may result in an overflow of fluid in the pipes down in your crawl space.

As a result, the nasty wastewater from your sewage pipes spills and collects in your crawl space and gives off a very unpleasant smell.

Microorganisms and debris in sewage water may produce hazardous vapors that settle in the air.

Ignoring your sewage issues may cause serious health problems. In addition, sewage leaks may contaminate your water source.

A clogged sewer line may be caused by the following:

  • Several blockages in various drains
  • Normal wear and tear
  • Broken pipeline due to corrosion or man-made factors
  • Tree roots invading the pipelines
  • Constantly flushing items in your toilet that may obstruct the pipeline (diapers, plastic bags, sanitary napkins, cleansing wipes, toys, etc.)
  • Temperature fluctuations
  • Grease, oils, and large food particles poured down the kitchen sink

To tell if your sewer line is clogged or damaged, watch out for the following:

  • The water remains stagnant or drains slowly
  • Backflows in your toilet, sink, or tubs accompanied by foul odor
  • Water buildup in your yard (specifically in areas above the main pipe)

More Reasons Why Your Crawl Space Smells

If a clogged or severed sewer pipe is not the problem, the reason may be one of the following:

  • Sewage pipes with cracks or leaks (due to outdated sealant or mechanical damage)
  • Accumulation of groundwater that may eventually start to smell
  • Dysfunctional or stagnant sump pump
  • Decaying animal cadavers (usually rats)
  • Rodent feces or urine

What to Do About The Sewer Smell in Your Crawl Space

Installing an exhaust system to temporarily halt the issue with the sewage smell is not the smartest option, and is clearly a waste of money and resources.

The best way to get rid of the unpleasant odor is through long-term fixes that focus on the underlying causes of the issue.

1 – Hire a professional

Your experts are always the best people to call when problems with your sewage system arise.

Most of the time, major problems like these will only be aggravated by careless do-it-yourself solutions.

Your local plumbers are equipped with the right tools and equipment to troubleshoot, remove debris and obstructions, repair damages, and in some cases, replace your pipelines.

2 – Properly Clean Your Crawl Space

After having your sewage line problem fixed, usually, the next step is removing the accumulated dirt and fluid in your crawl space.

You’re well aware that sewage water is really dirty and heavily contaminated, not to mention all the dust, airborne spores from molds, and toxic fumes that you might inhale.

In addition, letting sewage water sit in your space for a long time will compromise structural integrity.

When cleaning your crawl space, remember these tips:

  • Use protective gear like gloves, goggles, waterproof coveralls, boots, and a respirator (preferably N95 or higher).
  • Avoid using electricity-powered equipment to prevent shocks.
  • If there are electrical connections in your crawl space, be sure to turn off the power source first.
  • If there are items in your crawl space, remove them prior to cleaning.

These items are contaminated. You can disinfect non-permeable items like the ones made of glass and plastic, while porous objects like paper and fabric should be discarded.

  • Be sure to properly maintain your crawl space after cleaning up.
  • Always make sure to deodorize the area right after.

You can use lime, baking soda, or activated charcoal.

  • Reach out to industrial experts if unsure about what to do.

3 – Consider Encapsulating Your Crawl Space

Encapsulating your crawl space will improve the circulation of air within your house, prevent pest infestation, and reduce moisture.

All in all, encapsulation promotes healthy living conditions by forming barriers that serve as a seal in your crawl space.

4 – Avoid Unhygienic Practices

Properly dispose of your waste. Your sewage system is not built to manage solid waste.

Final Thoughts

A clogged sewer line is often the main cause of sewer-like smell in crawl spaces. As a result, wastewater backs up in sinks or toilets. It may also leak and accumulate in the crawl space.

Other reasons like leaking pipes, and decayed animal carcasses, may cause the problem. To solve the problem, seek the help of experts and do not attempt doing it yourself.

Always observe safety practices when cleaning your claw space.

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