My wife and I just bought a house and have been smelling sewer gases from our tub. After taking a look at the piping, the tub doesn't have a p-trap. My original plan is to install a trap before the sink's tie-in, but I have two questions:
1) With the current piping, is a tub trap all that I need?
2) What is up with the vent being after the toilet tie-in?
Attached is a simple drawling of the plumbing, and here's the description:
We live in a rancher house, with a main floor and basement underneath (Where all the piping connects)
The main air vent (2" diameter / Purple line in the drawling) runs from the roof down to the basement ceiling
The tub's drain connects directly to it's overflow pipe, and then runs straight down to the basement ceiling (Total length of pipe to the basement is about 2ft)
The tub's piping in the basement runs straight into the sewer line (Orange line in the drawling / Total length of the basement run to sewer line is an additional 5ft)
The bathroom sink has a trap underneath, which empties into the tub's line in the basement
The Toilet (with built-in trap ties directly into sewer line 6 inches down from where the tub's line connects into the sewer line
The Air vent line ties directly into the sewer line 6 inches down from where the toilet ties into
Does this make sense that the air vent would be so far down the line (After the tub, sink and toilet)?
Thanks for your time! :)
P.S. Here's a few notes:
- This house was built in 1972
- When the house was built, it originally had a septic tank, but since the early 2000s, it has been on city sewer (Not sure of exact date)
- The tub, sink and toilet drain without an issue (No gurgling or slow draining)
Edit: I had some time to take pictures of the actual plumbing, see below:
2) Tub - Overflow and Drain Connection
3) Tub - Piping to Basement
4) Tub - Piping in Basement
5) Sink - Piping to Basement
6) Sink - Piping in Basement
7) Tub and Sink - Connection to Sewer Line
8) Toilet and Air Vent - Connection to Sewer Line