Combining Bathroom Ceiling/Drain Vents

Discussion in 'Plumbing Forum, Professional & DIY Advice' started by P. Martin, Oct 8, 2005.

  1. P. Martin

    P. Martin New Member

    Oct 8, 2005
    I purchased a home 3 years ago and continue to uncover wonderful shortcuts by the builder. Most recently, when diagnosing poor venting in both upstairs bathrooms, I found that the ends of the vent hose terminated in the attic (buried in the insulation).

    Due to lofted celings there is no room to send the vent hoses to the front or back of the house without hitting the roof line. The gable ends of the house are accessible, but are a good 15-20' away in either direction and I'm afraid the fans are not adequate to push that distance.

    I am uncomfortable making a new hole in the roof. One person suggested that I tie into the 3" plumbing vent that runs within a few feet of the ceiling fans. Is there anyway to do that successfully, or am I asking for trouble?


  2. Terry

    Terry Administrator Staff Member

    Aug 17, 2004
    Bothell, Washington
    Not a good idea to tie into plumbing vents for your fan.

    Cutting the roof is not a big deal and would give you the best ventilation.
    They make roof jacks just for that purpose.
    Sewer gas should be kept seperate from your ventilation system.
    Last edited: Oct 9, 2005
  3. Sponsor

    Sponsor Paid Advertisement

  4. hj

    hj Moderator & Master Plumber Staff Member

    Aug 31, 2004
    Cave Creek, Arizona

    How does asking for "big trouble" sound to you. Sewer gases would flow from the drain into the fan vent and from there into the rooms. It is not really a "bad" idea, it is a "horrible" idea.
Similar Threads: Combining Bathroom
Forum Title Date
Plumbing Forum, Professional & DIY Advice Combining vents. Please proof my layout. Jun 6, 2014
Plumbing Forum, Professional & DIY Advice Combining vents in attic Jul 27, 2013
Plumbing Forum, Professional & DIY Advice Combining Vent Pipes May 2, 2010
Plumbing Forum, Professional & DIY Advice Combining 3x3x2 wye + 1/8 turn May 21, 2008
Plumbing Forum, Professional & DIY Advice Combining sink and toilet's water pipes? Oct 6, 2007

Share This Page