I am a newbie at plumbing and I want to install a Kerdi Shower in my basement. The house was built in 1959 and has a full bath on the first floor along with a sink and toilet in the basement. The basement fixtures were installed when the house was built.
I noticed that both the sink and toilet in the basement are not vented and the exit directly into the floor. Both basement fixtures are about 15 feet from the main stack. If I were to install the shower, the shower would be located between the toilet and the main vent and tied into the main sanitary between the toilet and the vent (in the floor).
Q1: The shower is still at least 10 feet away from the main vent. Due to this distance, I am assuming the shower must be vented due to its distance - is this true?
Q2:Why aren't the other two (existing) fixtures vented?
Q3: Do I have to worry about wastewater from the shower possibly existing floor drains (due to the volume of water)?
Thanks for everybody's input. If there is additional info needed, let me know.
1. 10' is too far to function as a vent for this, you need one closer.
2. Hard to say...
3. If the shower is vented, trapped, and you have the proper slope, no, unless the line gets clogged.
If the stack is draining things from upstairs, you can't (or at least shouldn't) run your vent into it unless you do it above the flood plane of the highest drain (i.e., probably in the attic would be easiest). You might find it easier to just run a new separate vent in a more convenient place.
Important note - I'm not a pro
Retired Defense Industry Engineer; Schluter 2.5-day Workshop Completed 2013