This house had a strange smell nobody could diagnose - call a home inspector instead!
Many companies had been in the house - air quality companies, mold search and destroy companies, pest companies looking for dead animals, HVAC companies - well, the term "many companies" applies. Their solutions were each different, each complex, and each EXPENSIVE!
The smell? A mixture of jock strap, running shoes after a rainy marathon, morning breath, old shrimp shells, and, um, sewer gas. The basement smelled! They said it smelled worst in the morning, and they would not go into the basement.
The smell was most pronounced near the HVAC equipment.
I noticed a few of things:
1. A new HVAC system.
2. Sheet metal taped over the hole in the metal duct where the old humidifier used to be.
3. There is no humidifier now.
4. The old humidifier drain line was laying on the floor.
5. The old humidifier drain tubing, with a P trap, was uncapped.
My diagnosis took less than 1 minute.
This was an easy one!
The hint is the red arrow.
We have just come off a winter with a new furnace and an unused humidifier drain line.
Since the old humidifier was removed, no water had drained into that line indicated by the red arrow for many months.
And over that time the water in the trap had evaporated.
The trap TRAPS water to prevent sewer gases from re-entering the house from the sanitary drain system.
If there is no water, there is nothing to TRAP the sewer gases, and they enter the house when the plumbing is used.
What happens in the morning? Showers, morning hygiene and kitchen activity. The sanitary drain fills with flushed and drained water. As the water enters the drain, the putrid air inside is displaced. Air will go where it is allowed to go. It is supposed to exit through the vents on the roof. But!
HERE SOME PUTREFIED, SEWER-GAS-RIDDEN, AIR WAS DISPLACED INTO THE HOUSE.
And they smelled it!
My solution: a plastic drain cap glued over the hole indicated by the red arrow. Cost - about $5.
My recommendation: a home inspector is a detective who has no financial interest in the problem(s) he is asked to objectively identify and perhaps solve. The solution to this problem was logical and cheap. And the problem was solved. May I suggest you contact a home inspector first? Who knows, you may just find he comes through big!
Jay Markanich Real Estate Inspections, LLC
Based in Bristow, serving all of Northern Virginia.
Office (703) 330-6388 Cell (703) 585-7560