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PLUMBING TOPICS
SEPTIC SYSTEMS HOME
SEPTIC SYSTEMS ONLINE BOOK
SEPTIC SYSTEM DESIGN BASICS
SEPTIC DESIGN ALTERNATIVES
SEPTIC INSPECTIONS
SEPTIC & CESSPOOL SAFETY
  TANK, & CESSPOOL WARNINGS
  SPECIAL WARNINGS FOR HOME OWNERS
  SEPTIC METHANE GAS
SEPTIC SYSTEM FLOODING
SEWER GAS ODORS
  First Steps for Sewer Gas Odors
  Dangerous Conditions
  Building Drain & Sewer Line
  Cure Odors in Septic Systems
  Other Causes of Odors from a Septic System
  Plumbing Fixtures or Traps
  Plumbing Vent Definitions, Types
  Plumbing Vent Defects
  Septic System or Sewer Piping
  Site, Weather, or Failing Neighbors
  Tests for Indoor Sewer Gas
  Tracking Odors to Source
SEWER GAS ODORS in COLD WEATHER

More Information
ODORS in BUILDINGS

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Open sewer cleanout in basement (C) Daniel Friedman

Diagnosing and Curing Sewer or Septic Odors Caused by Building Drains
SepticAPedia ^©

How to diagnose septic or sewer odors coming from building drain piping
How to prevent or cure sewer gas odors from septic systems, building plumbing, & other causes
Sewer gas smell diagnosis - plumbing checklist
Septic gas smell diagnosis - septic system checklist

Our site offers impartial, unbiased advice without conflicts of interest. We will block advertisements which we discover or readers inform us are associated with bad business practices, false-advertising, or junk science. Our contact info is at inspect-ny.com/appointment.htm.

This page describes how to diagnose, find, and cure odors in buildings caused by leaks or other defects in the building drains or sewer line - leaks that make sewage smells or sewer gas smells or "gas odors" in buildings with a focus on homes with a private onsite septic tank but including tips for owners whose home is connected to a sewer system as well. What makes the smell in sewer gas? Sewer gases are more than an obnoxious odor.

Because sewer gas contains methane gas (CH₄) there is a risk of an explosion hazard or even fatal asphyxiation. Sewer gases also probably contain hydrogen sulfide gas (H₂S) In addition some writers opine that there are possible health hazards from sewer gas exposure, such as a bacterial infection of the sinuses (which can occur due to any sinus irritation).

Depending on the sewer gas source and other factors such as humidity and building and weather conditions, mold spores may also be present in sewer gases. Also see CLOGGED DRAIN DIAGNOSIS, Drain Noises (gurgling drains means bad vent piping or clogged drains).

Citation of this article by reference to this website and brief quotation for the sole purpose of review are permitted. Use of this information at other websites, in books or pamphlets for sale is reserved to the author. Technical review by industry experts has been performed and is ongoing - reviewers welcomed and are listed at "References."

© Copyright 2008 Daniel Friedman, All Rights Reserved. Information Accuracy & Bias Pledge is at below-left. Use links at the left of each page to navigate this document or to view other topics at this website. Green links show where you are in our document or website.

Building Drain & Sewer Line Defects Can Release Sewer Gases & Odors Indoors

Check for a cap left off of a sewer line cleanout:

Our client is pointing out an open sewer line in the basement of a home she was purchasing. The cap had been left off of a cleanout port where main waste line exited the building.

We suspected more trouble than just an open drain cleanout permitting sewer gases to leak into the basement.

Because this "work" appeared to have just been performed, right before our property inspection, we wondered if someone had been asked to attempt to clear a blocked connection between the building sewer line and the community sewer (or private septic system).

Inspect the building drains and gas lines for leaks: Plumbing drains and traps may smell regardless, as they are usually a reservoir for organic debris.

Remember that a building drain can be leaking inside of a wall or ceiling cavity without showing up as a wet spot or mold.

But if you notice a sewer gas smell particularly at one or more plumbing drains, the fixture may not be properly vented.

If the plumbing fixture or drain "gurgles" or makes funny noises when it is draining, or if you hear gurgling noises at some fixtures, say a sink or tub when nearby fixtures are draining, we would certainly suspect that the fixture is not well vented or may not be vented at all.

If you suspect that odors are due to a problem with the building drains but you cannot find a drain line leak nor an open drain cleanout cover, take a look at CLOGGED DRAIN DIAGNOSIS.

Use links at the left of each page to navigate this document or to view other topics at this website. Green links show where you are in our document or website.

SEWER GAS ODORS
  First Steps for Sewer Gas Odors
  Dangerous Conditions
  Tracking Odors to Source
  Plumbing Fixtures or Traps
  Building Drain & Sewer Line
  Septic System or Sewer Piping
  Cure Odors in Septic Systems
  Site, Weather, or Failing Neighbors
  Other Causes of Odors from a Septic System
  Tests for Indoor Sewer Gas
SEWER GAS ODORS in COLD WEATHER

The Septic Systems Online Book - Where Are We?

This Chapter: SAFETY WARNINGS
Next Chapter: SEPTIC SYSTEM DESIGN BASICS
First Chapter: SEPTIC SYSTEMS ONLINE BOOK

Technical Reviewers & References

Particular thanks are due to experts and also consumers who read these articles and suggest corrections, changes, and additions to the material. Content suggestions, technical corrections and content critique are invited for any of the content at our website.

Daniel Friedman - InspectAPedia.com ^TM Website Author/Editor
Thanks to Slade Franklin for the reminder that a leaky wax ring at a toilet can lead to septic odors in bathrooms. 11/2007
Thanks to J.V. (privacy protected) for the reminder to make a detailed inspection of the plumbing vent system when sewer gas odors are present. 07/2008
Thanks to Roger Hankey & Cheryll Brown, www.hankeyandbrown.com, ASHI home inspectors in Minnesota, for the deteriorated transite pipe gas flue vent photograph and comments. Mr. Hankey is a past chairman of the ASHI Technical Committee, serves as co-chairman of ASHI legislative committee, and has served in other ASHI professional and leadership roles. 7/2007.
Critique, contributions wanted: Contact Us to suggest text changes and additions and, if you wish, to receive online listing and credit for that contribution.

Use links at the left of each page to navigate this document or to view other topics at this website. Green links show where you are in our document or website.

More Information on Building Diagnostic Inspections and Repairs

Cold Weather Septic Odors or Sewage Odor Diagnosis for additional odor tracing and cure advice focused on sewer gas odor tracking in cold or wet weather.
Drain Noises: may indicate defective or clogged plumbing: how to diagnose and cure drain sounds

The Septic System Information Website home page for this topic
Septic Systems Inspection, Testing, & Maintenance- online textbook. Detailed how to inspect, maintain, repair information
The Home Buyer's Guide to Septic Systems
Septic Tank Pumping Guide: When, Why, How to pump the septic tank
Home & Outdoor Living Water Requirements
Septic Tank Capacity vs Usage in Daily Gallons of Wastewater Flow, calculating required septic tank size, calculating septic tank volume from size measurements
How Big Should the Leach Field Be? - table of soil percolation rate vs. field size
Septic System Drainfield Absorption System Biomat Formation - what leads to drain field clogging and expensive drainfield repairs
Table of Required Septic & Well Clearances: Distances Between Septic System & Wells, Streams, Trees, etc.
What is a Septic System An Engineer's View - Types of treatment tanks, adsorption systems, pumps, and other special equipment are discussed in some further detail in this text
Components of a Septic System- the Basic Parts of a Conventional Septic Tank and Leachfield, a chapter in the Home Buyers Guide to Septic Systems
A Toxic Gas Testing Sampling Plan for Residential Indoor Air Investigations

Pennsylvania State Wastewater Treatment Fact Sheet SW-161, Septic System Failure: Diagnosis and Treatment
Pennsylvania State Wastewater Treatment Fact Sheet SW-162, The Soil Media and the Percolation Test
Pennsylvania State Wastewater Treatment Fact Sheet SW-l64, Mound Systems for Wastewater Treatment
Pennsylvania State Wastewater Treatment Fact Sheet SW-165, Septic Tank-Soil Absorption Systems
Document Sources used for this web page include but are not limited to: Agricultural Fact Sheet #SW-161 "Septic Tank Pumping," by Paul D. Robillard and Kelli S. Martin. Penn State College of Agriculture - Cooperative Extension, edited and annotated by Dan Friedman (Thanks: to Bob Mackey for proofreading the original source material.)

InspectAPedia^® Home & Site Map - Building & Environmental Inspection, Testing, Diagnosis, Repair, & Problem Prevention Advice: In-depth research & advice on diagnosing, testing, correcting, & preventing building defects & indoor environmental hazards. Unbiased information, no conflicts of interest.

The Mold Information Center: What to Do About Mold in Buildings, When and How to Inspect for Mold, Clean Up Mold, or Avoid Mold Problems

Use this simple, economical mold test kit by following our instructions on how to collect and mail mold samples to our lab

Environmental Inspection, Testing, & Diagnosis On-Site IAQ, Gas, Air Testing, Mold Investigation, Sick Building Diagnosis, Lab Services, & Remediation Plan Preparation - indoor air quality testing, problem source determination, supporting lab work, written remediation plan addressing removal of environmental and other hazards and prevention of their recurrence.

Building Inspection, Problem Diagnosis, Forensic Investigation & Testing, Repair Consulting

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