Venting Saniflo (or similar) Macerator From Basement

**Grybas44** · 01-01-2011, 07:59 AM

I am in the planning stage of finishing my basement. Part of the finish includes a half bath with a toilet and sink. I am intending to use a Saniflo (or similar) macerator for removal of waste and water. I have found step-by-step instructions through forums, websites, and videos explaining the installation process. However, the one bit of information that seems to be overlooked every time is the installation of a vent line.

I plan to locate the bath under a junction where my two bathrooms and laundry room are located. I have clear access to the water and septic lines. My house is a ranch with ample room in the attic to access the existing vent pipe.

How can I go about venting the macerator? Do I need to drill from my basement to the attic? Saniflo has already said that their system does not work with air admittance valves (AAVs). Since all fixtures need to be vented, would I still be able to place an AAV on the sink, and do a normal venting on the macerator itself?

Thank you.

**jadnashua** · 01-01-2011, 08:57 AM

WHen waste tries to go into the tank of the Sani-flow, it must displace air (out). An AAV only lets air in, so the waste will have a hard time getting in. That's why it needs an atmospheric vent line. Yes, run it into the attic and then attach it to an existing vent before it goes through the roof, or make a new penetration specifically for it. You'd be better off connecting the vent from the sink to this same line rather than using an AAV there.

**Grybas44** · 01-13-2011, 08:57 AM

Jim:

Thank you for the answer. A few of my friends were trying to convince me that it is perfectly fine to use a wet vent, but I do not intend to use their suggestions. How difficult would it be to run the vent pipe up through the existing walls on the first floor? I know that the wall separating the two bathrooms on the first floor hasn't any electrical or plumbing complications that could get in the way.

**cacher_chick** · 01-13-2011, 06:13 PM

Running a pipe through a wall is really not much different than fishing an electric wire through. It is mostly a matter of careful measuring and the right tools. In a single story home with good attic access, it is fairly easy task. Working on the roof during the winter is more challenging.