I have a basement bathroom with exhaust fan but I have no idea where it goes to. Finished basement with no way to look in joist area sort of cutting a hole in ceiling.
Is there any sort of colored smoke bomb that could help?
I have to be careful what I use as the wife has lung problems in case it leaks into the house.

I can find where the other bathrooms exhaust exits but have no clue where basement one goes.


Any suggestions?

Was the basement bathroom built with the original house build or later on?

Find the way the ceiling joist run(most run front to the back of the house). Usually, it will be exhausted out the back in the joist run the exhaust fan is in. I've seen them run out the front at times. It's hard to run an exhaust vent anything but up in the joist. If there is a HVAC duct run sometimes they will run it with that.

What kind of ceiling do you have? Drywall or drop?

Hate to tell you but I have seen some shady remodels/basement build-outs where they just vent it in the ceiling.

Can you shine a flashlight into the fan and see which direction the hose is going? If not, I'd try dropping the fan if it's fairly easy and seeing what direction the hose is going and see how far I can see it.

My basement bathroom fan goes up to the garage and then goes up the wall to the outside soffit.

It was not uncommon back in the day for them to dump bath exhaust into a joist bay, crawl space, or attic.

Run the fan, and look for exterior vents with airflow.

Depending on the age of your home, it could go nowhere, or into a space that is "vented."

It was also common to have "fans" that went nowhere.

Just because there is a fan, doesn't mean there is exhaust. People do all kinds of shit.

quote:

Originally posted by arcwelder76:
It was not uncommon back in the day for them to dump bath exhaust into a joist bay, crawl space, or attic.

Run the fan, and look for exterior vents with airflow.

Depending on the age of your home, it could go nowhere, or into a space that is "vented."

It was also common to have "fans" that went nowhere.

Just because there is a fan, doesn't mean there is exhaust. People do all kinds of shit.

I see it all the time, it's never been allowed by code, ever. It's homeowners and BS contactors that do it.

When I find it's the case I just tell homeowners I install the fan, you call HVAC Co, roofer, or handyman to compare duct run

My father was a "contractor." I've seen him fake more crap like exhaust fans into a joist than you can imagine. Drop the fan and look for the duct.

Bought house with the basement finished, drywall walls & ceiling. No way to see up above ceiling with out cutting drywall. If this fan is like the one I changed upstairs (looks the same) I will have to cut ceiling to get it down.
I am guessing it just dumps in joist area.