Move drain off vent

[robkeith]

Good day,

I am remodeling a bath and would like to move the sink drain from it's current location (where it's coming out of the wall through a cut in the side of the vanity) so that it comes out of the same wall as the supply lines). In the picture attached, you'll see the current layout where the trap pipe is attached to what I presume is the vent. I want to:

1) cut the ABS vent pipe above the connection to the drain pipe
2) cut the ABS pipe just past the elbow in the floor
3) use a Fernco to attach PVC that goes from the vent pipe, down into the floor to a "T" in the floor where you see the elbow. The "T" would then connect the vertical vent pipe, the new drain, and the plumbing going to the rest of the house.

Will that drain properly if I pull it off the direct vent and will it be to code?

Thanks,
Rob

[Jerry Peck - Codeman]

First, a few questions and comments:

1) The studs and plate in the wall where the vent is now looks to be larger (2x6?) than the wall where you want to move it to (2x4?) - is that correct?
- The pipe might not fit in that wall.

2) Is that 1-1/2 inch or 2 inch pipe for the vent and waste drain?

3) If everything physically fits in the other wall, you will need to run a vent up from the sink drain, around the corner, and over to reconnect with the existing vent (or use an AAV if allowed in your area, some AHJ do not permit AAVs to be installed) as you need to vent that sink drain.

4) There may be some other options, depending on distance, pipe size, stud size, etc.

5) If you did the "tee" below the floor, you would not be allowed to use a "sanitary tee" there, you would need a wye and an 1/8 bend (or a single combination wye and 1/8 bend fitting). Sanitary tees are made for changes in direction from horizontal (the drain) to vertical (the waste drain and vent going up), not for horizontal changes in direction as you describe.

[robkeith]

Thanks Jerry, good point about the studs. The studs in the wall where the vent is now, actually are 2x4's. The other wall studs are 2.5" deep (as in, it looks like they ripped 2x4's down). The vent and waste are 2" pipe.

It's not really very practical to attach a vent up and over, so if I stay under the floor and use a Wye and 1/8 bend, how would the Wye be connected? My sense is that the "straight" part of the Wye would go from the sink drain straight to the existing plumbing and the 90 degree bend in the Wye would go to the vent. Am I getting that right?

Also, I assume I have to use a Fernco (or similar) to connect ABS to PVC, correct?

Thanks again,
Rob

First, a few questions and comments:

1) The studs and plate in the wall where the vent is now looks to be larger (2x6?) than the wall where you want to move it to (2x4?) - is that correct?
- The pipe might not fit in that wall.

2) Is that 1-1/2 inch or 2 inch pipe for the vent and waste drain?

3) If everything physically fits in the other wall, you will need to run a vent up from the sink drain, around the corner, and over to reconnect with the existing vent (or use an AAV if allowed in your area, some AHJ do not permit AAVs to be installed) as you need to vent that sink drain.

4) There may be some other options, depending on distance, pipe size, stud size, etc.

5) If you did the "tee" below the floor, you would not be allowed to use a "sanitary tee" there, you would need a wye and an 1/8 bend (or a single combination wye and 1/8 bend fitting). Sanitary tees are made for changes in direction from horizontal (the drain) to vertical (the waste drain and vent going up), not for horizontal changes in direction as you describe.

[Jerry Peck - Codeman]

Rob,

... good point about the studs. The studs in the wall where the vent is now, actually are 2x4's. The other wall studs are 2.5" deep (as in, it looks like they ripped 2x4's down).

They likely use 2x3 studs and plate for that wall (2x3 is 1-1/2" x 2-1/2") as ripping a 2x4 in half would be less than 2".

Also, it doesn't make much sense to rip separate 2x4s down ... 'doesn't make sense' does not mean that is not what they did, contractors have been known to do many things which 'don't make sense'.

The vent and waste are 2" pipe.

Measure the overall OD of the fittings widest points - 2" pipe is about 2-1/2" OD, and the fittings go over the pipe, making the fittings even larger ... if that wall only has 2x3 studs for 2-1/2", that is not going to fit inside that wall. You would need to fur the wall out with minimum 1x2 (3/4") to get 3"+ (3-1/4" basically) to get the pipe and fittings into that wall.

It's not really very practical to attach a vent up and over, so if I stay under the floor ...

no, it is not practical, but you will still need to vent the sink drain some way. Are AAVs (Air Admittance Valves) allowed by your building code?

... and use a Wye and 1/8 bend, how would the Wye be connected? My sense is that the "straight" part of the Wye would go from the sink drain straight to the existing plumbing and the 90 degree bend in the Wye would go to the vent. Am I getting that right?

Also, I assume I have to use a Fernco (or similar) to connect ABS to PVC, correct?

Correct on both.

And make sure to get the correct Fernco couplers, they will have what they are for stamped/molded into each end of the coupler fitting.

[robkeith]

Thanks again, Jerry.

Good info re: furring out the studs to fit the pipe. I figure worst case scenario is that I come up through the floor and bottom of the vanity. That will at least hide the drain pipe vs coming in from the side.

Re: the AAV, I don't know, that's a terrific question. I'm remodeling to sell the house, so if it passes inspection, then I'm ok with using them if I have to. How often do AAVs fail?

Re: the Fernco, attached is the one I bought. I measured the pipe on the outside to determine the 2" dimension.

Rob

Rob,

... good point about the studs. The studs in the wall where the vent is now, actually are 2x4's. The other wall studs are 2.5" deep (as in, it looks like they ripped 2x4's down).

They likely use 2x3 studs and plate for that wall (2x3 is 1-1/2" x 2-1/2") as ripping a 2x4 in half would be less than 2".

Also, it doesn't make much sense to rip separate 2x4s down ... 'doesn't make sense' does not mean that is not what they did, contractors have been known to do many things which 'don't make sense'.

The vent and waste are 2" pipe.

Measure the overall OD of the fittings widest points - 2" pipe is about 2-1/2" OD, and the fittings go over the pipe, making the fittings even larger ... if that wall only has 2x3 studs for 2-1/2", that is not going to fit inside that wall. You would need to fur the wall out with minimum 1x2 (3/4") to get 3"+ (3-1/4" basically) to get the pipe and fittings into that wall.

It's not really very practical to attach a vent up and over, so if I stay under the floor ...

no, it is not practical, but you will still need to vent the sink drain some way. Are AAVs (Air Admittance Valves) allowed by your building code?

... and use a Wye and 1/8 bend, how would the Wye be connected? My sense is that the "straight" part of the Wye would go from the sink drain straight to the existing plumbing and the 90 degree bend in the Wye would go to the vent. Am I getting that right?

Also, I assume I have to use a Fernco (or similar) to connect ABS to PVC, correct?

Correct on both.

And make sure to get the correct Fernco couplers, they will have what they are for stamped/molded into each end of the coupler fitting.

[Jerry Peck - Codeman]

Check with the building department about the AAV before you start the work, otherwise you may find out after doing all the work that you have to remove or change all your work at the time of your inspection - not something you want to find out then.

The AAV would be mounted in the cabinet under the sink.

AAV rarely fail when installed properly, and they are required to be accessible for replacement if needed. They also require ventilation (they allow air in, but not out), thus they are not to be sealed up in a wall, and a cabinet allows sufficient ventilation.

If you measured the outside of the pipe at 2 inches, the pipe will be 1-1/2 inch pipe (pipe is measured inside diameter). Hold that Fernco next to the pipe and see how much larger it is.

Also, what state are you in? Some states have licensing and require licensed conductors when doing work for others - and that is essentially what you are doing being as you are planning on selling it. Some states require the use of licensed conductors if sold or rented, or offered for sale or rent within one year of completing the work ... I.e., you did the work for others.

[robkeith]

I have a message into the building dept re: the AAV. I read the code and it's not terribly clear.

I'm in Virginia (Fairfax County), so good to know about the license contractor possibility. Are you familiar?

Thanks,
Rob

[Jerry Peck - Codeman]

Rob,

I'm in Virginia (Fairfax County), so good to know about the license contractor possibility. Are you familiar?

I'm not familiar with Virginia statutes, but a Google search found this (among other things, but this is the best of what I found): (right click over the ilnk, select 'open in new tab' or 'open in new window') http://www.dpor.virginia.gov/uploadedfi ... 27regs.pdf

Read through this part: (on file page 46 of 78, document page 41) § 54.1-1101. Exemptions; failure to obtain certificate of occupancy; penalties.
- I didn't see an exemption for what you are doing.
- The closest exemption may be this one, but it indicates that there is a 24-month period of ownership when it states "for his own use": (at bottom of same page as above)
- - 7. Any person who performs or supervises the construction, removal, repair or improvement of no more than one primary residence owned by him and for his own use during any 24-month period;

Short of having an attorney review the statutes and rules for their opinion of what you are doing (this could be somewhat costly), I recommend sending an email to their Board of Contractors (email: contractor@dpor.virginia.gov ) and asking them about any requirements for an owner-developer (their term as used in the linked document above) who is doing the work themselves and will then be selling the property/building which the work was done on (this would likely be no cost). They can tell you what is required and what time frame of ownership there is after the work is done ... and it will be in writing because it is email, keep their answer in writing in case you need it when selling.

[robkeith]

Wow, terrific info!!! Thanks!