No one wants to walk into their home and be greeted by the unpleasant smell of sewer gas. Beyond being a hassle, these odours could pose health risks if not addressed properly. If you’ve noticed that unmistakable smell, you’re probably wondering where it’s coming from and how to get rid of it.
This blog will explore the causes of sewer gas smells in your home, ways to detect the problem, DIY solutions, and when it might be time to call in a professional. Plus, we share actionable tips to prevent future occurrences. Whether you’re a seasoned homeowner or a first-time buyer, this guide will help you tackle this stinky situation with confidence.
What Is Sewer Gas, and Where Does It Come From?
Sewer gas is a mixture of various gases that come from decomposing organic matter in sewer systems. Its composition typically includes hydrogen sulfide, methane, ammonia, carbon dioxide, and traces of other gases. These gases are not only unpleasant but can also be hazardous to health, especially in enclosed spaces.
Normally, a functioning plumbing system prevents these gases from entering your home. However, certain issues can cause them to seep into your living space, leading to that recognizable foul odour.
Common Causes of Sewer Gas Smells in Homes
Understanding the root causes of sewer gas smells is key to resolving the issue effectively. Here are some of the most common culprits.
1. Dry P-Traps
The P-Trap is the curved segment of pipe located under sinks, showers, and other drains. Its purpose is to hold a small amount of water that acts as a barrier, preventing sewer gases from coming up through the pipes.
However, if a drain hasn’t been used in a while, the water in the P-Trap can evaporate, leaving it dry and ineffective at blocking the gas. This is one of the most frequent causes of sewer gas smells in unused guest bathrooms or basements.
2. Blocked or Damaged Vents
Plumbing systems include sewer vents, which allow gases to escape into the outdoor air. When these vents become blocked (due to debris, nests, or ice) or damaged, it can lead to gas accumulating in your pipes—and eventually escaping into your home.
3. Cracked or Damaged Pipes
Cracks or damage in your plumbing pipes can allow sewer gas to leak directly into your home. These issues can happen over time due to aging pipes, natural wear and tear, or damage from external factors like tree roots. Cracked pipes not only cause odours but can also lead to leaks, which could result in water damage or mould growth.
Detecting Sewer Gas Smells
Not sure if the smell in your home is caused by sewer gas? Here are some signs to look out for:
- Rotten egg smell (caused by hydrogen sulfide)
- Unexplained headaches, dizziness, or nausea (potential health effects of sewer gas exposure)
- Smells that worsen near drains, toilets, or vents
- Consistent odour in specific rooms like the basement or bathroom
If any of these ring a bell, it’s time to investigate further.
DIY Solutions for Eliminating Sewer Gas Smells
Before calling a professional, try these DIY fixes to resolve the issue on your own.
Refill Dry P-Traps
If you suspect a dry P-Trap is the problem, simply pour a few cups of water into the drain to refill the trap. To keep the water from evaporating too quickly, add a tablespoon of vegetable oil—this creates a barrier that prevents evaporation.
Clear Blocked Vents
Head outside and check the sewer vent on your roof for blockages. If it’s accessible and you feel safe doing so, use a plumber’s snake or a garden hose to clear debris. Pro tip: Enlist a helper to assess improvements in indoor air quality while you’re cleaning.
Check for Minor Leaks
Inspect the pipes in the areas where you’ve noticed the smell. Look for visible cracks, loose connections, or damp spots. Tighten loose joints where possible and use the plumber’s tape as a temporary fix.
While these solutions can address many minor issues, it’s important to know your limits when it comes to plumbing. Some problems require professional expertise.
When to Call a Professional
There are certain situations where it’s best to contact a licensed plumber to handle sewer gas issues, such as:
- The odour persists despite your DIY efforts.
- You suspect a cracked pipe or major structural damage.
- There’s visible water damage or mould around the affected area.
- You notice other plumbing issues, like slow drains or unusual gurgling sounds.
Professional plumbers have specialized tools (like smoke tests and sewer cameras) to identify unseen leaks or damage. Plus, they can perform repairs safely and efficiently to ensure no further issues arise.
Preventing Sewer Gas Smells in the Future
Once you’ve resolved the issue, it’s essential to take steps to prevent sewer gas smells from returning. Here’s how you can keep your home odour-free moving forward.
- Run taps regularly in sinks that aren’t used often to keep P-Traps filled.
- Inspect and clean sewer vents seasonally to prevent blockages.
- Schedule annual plumbing maintenance to identify potential issues before they escalate.
- Seal floor drains in areas like basements with rubber stoppers or covers.
A little proactive maintenance can go a long way in keeping unpleasant sewer gas smells at bay.
Sewer gas odours can be unsettling and even harmful, but understanding the causes and solutions can help you tackle the problem effectively. Whether it’s a dry P-Trap, a blocked vent, or damaged pipes, addressing these issues promptly will ensure a safer and more comfortable home environment.
If you’ve battled sewer gas smells before, we’d love to hear your story—share your tips below! And if you’re dealing with a lingering issue, don’t hesitate to contact a plumbing professional for expert assistance.
