Hello all! Been lurking and learning. Thanks!

I have a tricky retrofit in progress. The homeowner bought a house "sight & smell unseen" at a foreclosure auction. Its a two floor cape, one bath, one clothes washer in utility room, kitchen sink/dishwasher. Its on a slab and all plumbing is on ground floor. 3" horizontal pvc main installed in 2001 (from what I can determine). ~11 du total. Vent is a 90 through 1st floor exterior wall @ about 7' above grade and ends. Just ends. Interior smells of sewer gas.

From sewer line the connections are as follows:
Sewer -> kitchen sink/dw -> utility drain (sanitary-tee) -> (first wye) -> (second wye) -> 3" to 1 1/2" reducer -> 1 1/2"vent
..............................................................(first wye) -> bathtub
.......................................................................(second wye) -> basin -> toilet


Sewer entry to utility drain was 3" pvc flat horizontal (I mean flat!). 13'. Yuck. (I won't mention the mickey mouse connection on the subgrade exterior to septic...).

Bathtub (wye) and utility (san-tee, v-2-h) enter main "stack" with back to back fittings. Basin/toilet branch is 3" pvc at 1/4" per foot (good).

Owner correctly identified an unvented utility room drain (~10' x 2" PVC from trap to the below fernco) and "correctly" installed a 1 1/2" vent branch from about a foot behind the 2" p-trap to the existing vent (above flood). Did not fix his smell...

After I removed the kitchen base cabinets and subfloor over the 3" main, I found a poorly connected (too short) and dry-rotten Fernco tee (which was the utility drain into stack). This fitting was leaking badly and cause of smell. I plan to add an AAV on the bathroom basin (I don't see a vent on this branch).

There is no access from the existing dwv to 2nd floor roof. The 2nd floor has a smaller footprint than the first floor. In order to do a "proper" vent, I'd have to convince the owner to rip up and re-drywall two bedrooms, the kitchen, the tiled bath and the utility room. There is no easy access to the upstairs interior or exterior walls. I thought about accessing from exterior, but there are multiple layers of siding, foam board and sheathing. Even if I could convince the owner of the need, the number of ells to get up and over and up this thing is touching insanity.

I have replaced the three inch main with a new properly graded 4" main to the 3" utility/toilet connections (1/4" slope). Also put in proper cleanouts and connections below grade to septic tank.

I am at a loss as to what to do with the vent. I see these options:
1. Do nothing.
2. Rip up the whole back of the house.
3. Leave the 1 1/2" vent as is and put a charcoal filter on it (still 7' above grade on exterior wall).
4. Where the two 1 1/2" vents come together, replace to end of vent with 3" fittings & pipe, enlarge existing vent hole w/ charcoal filter (still 7' above grade).
5. Do #4, but route vent either through soffit/first floor roof (or around soffit/roof) and put the charcoal filter above the top of the 2nd floor windows. Probably about 8' of vent pipe exposed to exterior elements, ugly but white on white.. so maybe okay. This is in east-central New York state (we freeze in winter).
6. Do #5, but also route through 2nd floor roof soffit. Challenge here is ice buildup on drip edge could shear off the vent... Soffits are roughly 10-12 inches.

I am leaning towards #4... and open to #5 or #6. #2 would be a worst case... #1 seems wrong.

Suggestions & thoughts? Thank you for your time.

on this one, you will have to provide a picture or two. you understand that each trap must be protected from syphonage. this is accomplished by installing a properly located vent FOR EACH ONE... you can combine vents and you can wet vent a trap but you can not skip venting any trap.

Unfortunately pictures are tough. Most of this is under floor or behind walls. Used smoke to diagnose and camera to verify and map before cutting away select parts of the house. The bathroom basin and toilet are the "worst vented" as its about 4' of 3" wet vent then 1 1/2" of dry vent to the side of the house (the logical top of the horizontal stack). Making this completely right is a full gut of at least one 2x4 wall which is likely load bearing and multiple other walls to get through the roof. The rest is reasonable now, minus the fact that the entire vent to outside is only 1 1/2". Surprisingly this thing worked as-is through 3 owners and 15 years until a mis-installed Fernco rotted.

Key decision is to vent to roof ($1,000's) or to sidewall with charcoal (circa $200).

Town's Plumbing Inspector's opinion (with all due respect for a very tough job) is not valuable as he originally approved the as-is state and is proud of his work.

I just want it as good as possible, given the constraints, for my client who knows he's in a tough spot.

Thanks!

the town inspector approved a 7 foot tall vent open to the atmosphere inside the house ???
can't you get a picture of the piping you have replaced?

Here goes.

Existing 1 1/2" vent from outside. Room labels are circled. Schematic drawn approximate. The horizontal main is right on top of the slab... I had a 1" to 4" deep ditch carved in the slab to get 1/4" per ft grade. Overall slab depth is approx. 7" and does not support the wall which is cinder block on footer. Blue line is owners util room vent "fix".
[i1167.photobucket.com]

Leaking boot. The end pointed to was no longer attached to the upstream pvc. It either shrank or was never well connected to begin with. I believe this was installed in 2001.
[i1167.photobucket.com]

Bathroom view. Distances in red. Pipe size in black.
[i1167.photobucket.com]

New pipe, increased long run from 3" to 4" and graded properly. I wanted to go all the way to the toilet branch (inc. wye) with 4"... owner didn't want me breaking up the bathroom to do so.
[i1167.photobucket.com]

Hope this makes it a little more clear. Thanks!

Edit #1: Note: I used clear primer...so no purple. I had a half pint leftover from another job who wanted clear.

Edit #2: All plumbing shown in bathroom pic is embedded in concrete under tile.



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Sanitary tee on it's back is not legal as a drainage fitting.

it looks to me like the only proper LEGAL solution is to open it all up and start over. sorry..

Agree. This is a disaster. Wrecking ball is the defacto best option. Rebuild with proper mechanicals and better floor plan. Unfortunately does not affect the sales potential.

Anyway, lots of reasons, excuses and small town. Anyway I can help this guy make it better without a full gut?

Sanitary tee on back is due to kitchen cabinet clearance. Only inlet is a 7/8" clothes washer hose... to fit a proper wye he needs to either build a custom cabinet to replace existing or rebuild the wall, plate to cap (I've already argued it needs rebuilt anyway).

Perfect example of not all "good deals" being good deals.

Edit: For various unrelated reasons, I know the history of this house back to the 80's - it began its life as an independent mechanic's garage. Unfortunately there are too many just like it around here...



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Thanks for looking and confirming my suspicions. Last night I told the owner he needs to get comfortable with the idea of a new-from-the-studs bathroom & some fresh sheetrock upstairs... and to look me up when he wants it done right.



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