The bathroom that smelled worse with the fan on
Illustrative example. Not a real job or customer.
Illustrative example, not a real job or household. In May, a family in a 1950s house near Sloan's Lake notices a rotten smell in the upstairs bathroom. It gets stronger whenever someone runs the exhaust fan, and a few large flies collect at the bathroom window.
- They stop using the fan and open the window instead.
- From the yard, with a phone zoom, they see grass and twigs sticking out of the exhaust cap on the roof, and the flap is missing.
- A roofer removes the cap and finds a dead starling and a nest in the first few feet of duct.
- The short section of flexible duct is replaced, and a new cap with a working damper and bird guard is installed.
- The family wipes the fan grille and housing and runs the fan with the window open for a day.
The smell was gone within two days. The household later checked the dryer vent cap, which also had no guard, and had one fitted.
Bathroom with the toilet removed and the flooring taken down to the subfloor. A general example of this kind of work, not a photo of a particular home, business or job.
What pointed to the duct
- IfSmell surged when the fan ranThenThe fan was pushing air past the source in the duct.
- IfFlies gathered in the bathroomThenThe source was close to that room.
- IfNesting material showed at the capThenA bird had entered through a missing flap.
Lessons from the example
Exhaust caps without dampers or guards invite starlings and sparrows, which nest in spring. When a bird dies in the duct, running the fan sends the smell straight into the room. Checking the cap from the ground before calling anyone saved time and pointed straight to the repair.
Replacing the short flex duct was simpler than trying to clean it, and the new guard stops a repeat.
What made the fix stick
Replacing the missing flap with a cap that has a working damper and a guard was the key step. Without it, another starling would likely have nested in the same duct the next spring. Checking the other exterior caps at the same time found a second vulnerable spot before it caused a problem.
Common questions
Could the fan motor have been damaged?
Nesting material can strain a fan. If it sounds labored after the duct is cleared, have it checked or replaced.
Could the family have removed the bird themselves?
The cap was on a second-story roof, so a roofer was the safer choice. A ground-level dryer vent is a more reasonable do-it-yourself job with gloves and a mask.
General information for Sloan's Lake, not a quote or professional advice. In an emergency, call 911.