Home>Discussions>BATHROOMS>Combining Batroom Exhasut Vent w/Existing Vent
3 posts / 0 new
Last post
wetwindow
Combining Batroom Exhasut Vent w/Existing Vent

I would like to remove a 4" dryer type hose venting that runs to the gable vent and tie it into the existing PVC vent stack that goes through the roof. The PVC vent stack is much closer to the bathroom exhaust fan and I think it would more efficent. Are there any issues with tying these two together?

canuk
Re: Combining Batroom Exhasut Vent w/Existing Vent
Quote:

Are there any issues with tying these two together?

1 - the main plumbing vent stack also exhausts methane gas.
Tying the bathroom fan into this will allow an avenue for that sewer gas entering the home.

2 - the other function to allow air in for the drain system to function properly.
If you are pushing air out while there is a need for air in the drains you can have vacum locks and poor functioning drains.

I'd recommend leaving the vent stack alone to function as intended .

2 cents worth.

A. Spruce
Re: Combining Batroom Exhasut Vent w/Existing Vent

You definitely don't want to tie the two together, aside from the toxic gases coming into the room you'll also be getting sewer odors. What you can do is vent the bath through it's own roof penetration, the only caveat to this is if you live in cold climates the vertical vent could be prone to icing and freezing from the damp air being vented from the bathroom or possibly being covered by snow.

TV Listings

Find TV listings for This Old House and Ask This Old House in your area.