Locating vent pipe behind drywall?

[jhqpzjg]

Hey Folks,

I'd like to attempt to locate an abs vent pipe behind drywall. The vent services (I believe) several fixtures in the basement. All the fixtures are in the finished basement along a foundation wall. I believe the vent runs up the wall, makes a short 'jog' from the exterior wall toward the peak of the roof, then through the roof deck. There is no attic access to this vent, as the ceiling is vaulted in that area.

I poked a couple holes in the drywall under the vanity and found that that there is no vent directly above where the vanity drain enters the wall.

So, what are some ways to locate the vent in the basement wall without poking a bunch of holes? I'll try to attach a photo of the fixture arrangement.

Thanks,

Jason

 

[Geofd]

find the vent in the basement have someone tap on it see if you can hear it above

 

[jhqpzjg]

Hi Geofd,

Thanks for the reply. I probably should clarify. The basement and the main floor are both finished, so the vent pipe is not visible except where it comes out of the roof. I'd like to locate it in the basement wall, through the drywall without putting a bunch of holes in the drywall.

Since the original post, a friend suggested pouring hot water down the vent from on the roof and using an thermal imaging camera to look for the heat of the water in the vent pipe through the drywall. That means I have to find a thermal imaging camera, though. Any problems with this method? Other ideas?

Thanks,

Jason

 

[Geofd]

Hi Geofd,

Thanks for the reply. I probably should clarify. The basement and the main floor are both finished, so the vent pipe is not visible except where it comes out of the roof. I'd like to locate it in the basement wall, through the drywall without putting a bunch of holes in the drywall.

Since the original post, a friend suggested pouring hot water down the vent from on the roof and using an thermal imaging camera to look for the heat of the water in the vent pipe through the drywall. That means I have to find a thermal imaging camera, though. Any problems with this method? Other ideas?

Thanks,

Jason

do you have a medicine cabinet in your first floor bathroom?????maybe you could take it down and make a hole there.....
if you can see the vent on the roof ….and have access you could run an electric drain snake down it that way you may hear it

 

[jhqpzjg]

There is no bathroom on the first floor above the basement bathroom, unfortunately. I like the drain snake idea though...make noise that would be audible through the wall.

Based on the picture I included, is there an area where the vent would 'likely' be traveling upward from the basement? There are a number of fixtures, between the bathroom, washer/dryer and utility sink that use this vent. With those types of things all lined up along the wall, is there a 'typical' installation location for the vent? Like in line with a particular fixture out of those along the wall? It would seem to make sense to go as straight up the wall as possible, between studs, so that you could minimize having to put elbows in the pipe and cut holes in the studs, but maybe that's not always practical.

Thanks,

Jason

 

[ExtraMilePlumbing]

most vents takeoffs are above(6inches above flr of vanity)
the toilet because its the biggest pipe