Plumbing System and Bad Odors in Your House | PlumbRite


How the Plumbing System Can Cause Odors in Your House


guy working on plumbing

Problems with your plumbing system can fill your house with foul odors. When you understand the potential causes of those odors, you can prevent or deal with them. Below are some causes of such odors.

Drainpipes Blockages

Blockages in your drainpipes can cause unwanted odors in different ways. For example, clogged drainpipes allow wastes to decompose within the pipes. Decomposing wastes emit a foul odor that can flow back into the house.

Causes of drain blockages include:

  • Food wastes, such as coffee grinds, which don't break up easily in the garbage disposal
  • Mineral buildups within the drainpipes
  • Tree root intrusion into the drain pipes
  • Solid objects that people mistakenly flush down the toilet

Flush slow drainpipes before they clog to avoid such problems.

Venting Blockages or Inadequacy

Plumbing removes stale air from your plumbing system and allows fresh air to flow into the house. Thus, anything that interferes with air circulation through the vents can trigger foul odor in the house. For example, stale air from your plumbing system might circulate in the house if something blocks the plumbing system.

Dry P-traps

A P-trap is U-shaped piping between open drains and the main drainage systems. For example, a P-trap typically connects the kitchen sink's drain to the main drain line. One function of the P-trap is to prevent sewer gases from flowing back into the house.

The P-trap can only trap sewer gases if it has water. The trap can dry if you don't use your plumbing for some time, which will allow sewer gases to flow into the house.


Plumbing leakages in different parts of the house or plumbing system can also cause a foul odor. Below are some leakages of particular concern.


Damaged or disconnected drainpipes can spill wastes in your house. PVC pipes can crack, and metal pipes can develop holes due to corrosion. Damaged plumbing seals, such as toilet seals, also cause leaks. Drain wastes typically have a bad smell. Secondly, the wastes can also cause materials to rot and smell. Lastly, the wastes can encourage mold growth - and mold can smell bad.


Freshwater might not smell, but it can also cause rot or mold growth, both of which smell. Water issues usually occur over time and are common with hidden leaks.


Because natural gas is odorless, gas companies add smelly substances to their gas supplies. The additives help homeowners detect gas leaks and avert danger. People usually describe gas as having a rotten egg smell. Get out of the house and call 911, the local fire department, or your gas company if you detect such a smell in your house.

Septic or Sewer Backups

Septic or sewer wastes can sometimes back up into the house. For example, your septic waste can back up into the house if the tank is full and additional wastes have nowhere to go. The backed-up waste can smell, cause material rot, or emit its intrinsic foul odor just as drain leaks.

Debris Buildup in Appliances

Plumbing appliances that handle wastes can also smell if you do not regularly clean them. A good example is the garbage disposal that handles food wastes. The disposal needs regular cleaning to remove traces of food that remain inside the disposal every time you use it. Otherwise, the debris will decompose and emit an unwanted stench.

Hopefully, your plumbing problems won't cause serious complications in your house. Both minor and major plumbing problems can cause foul odors in your house. Contact PlumbRite for help if you cannot diagnose or clear such odors. We have over 20 years of plumbing experience and promise you superior plumbing service at cost-effective rates.

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