Vent line thru multiple king studs/top plate.

[BRycraft]

I have been reading a lot of the Q&A on this forum, looking thru plumbing and building codes trying to educate myself, and have a dilemma that I have not been able to find an answer for. Currently I am moving a kitchen sink about 7 feet to center under a window thats about 72" wide. I am going to place a kitchen island where the sink currently is and put in a small bar sink since the drain and supply are already there. I live on a slab and have to break up the concrete to run the drain and supply lines. My question comes in the installation of the vent. This obviously is an outside wall the vent pipe is entering which is under a window. I want to slope the vent up and to the side of the window and up thru a bay between king studs into the top plate into the attic. I have read about drilling a hole 40% the width of the stud but if there are 2 king studs you can drill up to 60% Since these are 2x4 seems a 2" line would not be to code since that exceeds the 40% rule, these studs have previously been notched for conduit to pass thru, so first can you even bore holes and also have notches as well within a short distance from each other?... I will install shoe plates, strapping whatever would be required. The drain is going to be 2" and would rather have a 2" vent because up the wall and over to where the current vent line is located is about 16' away not including the distance of pipe going into attic 8' foot ceiling, maybe 28 feet total run. Would 1 1/2" be ok or would 2" be better?, this is a farm sink and a dishwasher connected to this one drain and thats it beside further down the line will be the bar sink that will use the existing plumbing already in place..
Ok my real dilemma is because this is a large 3 lite slider window whoever built the house installed 3 king studs adjacent to the window with a cripple stud before the kind stud so essentially 4 studs together, and the next framing king stud is only 6" on center. I have read you can only drill thru 2 king studs to get the 60% allotment of hole size, so am I out of luck because of the 3rd king stud? even though there is another king stud 6" away? I want to run the vent in that narrow bay up into the attic. Seems a 3rd kind stud would be stronger then 2 and drilling a 2" hole would be 57%. Problem is I cannot get shoe plates for 4 studs and if they make them for 3 studs I can remove that cripple stud install a shoe plate and reinstall it back in place.
So is this more a building code issue? I have seen where someone piped around the outside of the king studs like a curve in a roundabout. This shouldn't be a problem because a dishwasher will be positioned right in front of these studs and there is enough room for the pipes without hitting the dishwasher.
I like doing things right and since I have had 2 plumbers here telling me 2 different things contradictory things, I prefer to find the right way and do it myself and save a boatload of money..
Whats are my options and what would be the best way? Can I even drill thru the studs that are already notched? Can I notch them myself the 25% just to recess the pipes somewhat? The drain will be coming out the floor and will install a cleanout as well, then run the vent into the back wall thru the cripple studs. I have read that its always best to slope the vent pipe upward, so I was thinking sloping the pipe upward to the side of the window and up the bay.. Next part of my question is the top plate, sandwiched 2x4 and I read that 40% rule applies but does the 60% rule apply since there are 2 top plates? I would rather not plumb out and around them into the ceiling because it will be visible, unless I move over another bay where it will be hidden by cabinets but thats drilling thru another king stud.. Can I drill thru the king studs and top plate and reduce the pipe to 1 1/2" thru those boards and go back to 2" for the runs, even at 1 1/2" it exceeds the 40%, how else do they manage to run pipe thru structure if most of the sizing exceeds the value allowed by code?
Also this is a single family home, single level so no upper level to deal with.
Currently the vent stack where its located is servicing a washing machine and the kitchen sink in its current location. The vent pipe is only 1 1/2" for the washing machine and the kitchen sink is 2", so the 1 1/2" pipe increases to 2" for the kitchen sink and then it increases to 3" going thru the roof, thats the current configuration. I figure to tie into that 2" pipe, however this probably won't fly but to save some time and working in a very hot attic would be a plus. I have a high efficiency furnace that is vented to the outside wall which would be about 10 feet above the window but is turned down with a 90 elbow and is a few feet from the soffit. I assume tying into the vent is prohibited? Just wondering.. Included photo of desired run of vent and current vent.
Or should I simply increase the vent to 3" in the attic and have it exit the roof the minimum 6"is that even allowable? Also one 1 other vent in home on other side of house for bathroom.

If I did use stud shoes do they allow for pipe on an angle?

Once I solve this problem I will be back with some other questions regarding the PEX I want to install for the supply lines...

Thanks for any help Bill

 

[Cacher_Chick]

I would run a 2" trap arm off the sink keeping it inside back of the cabinets until it is past the king studs, then into a new drain and vent stack in the wall. A 1-1/2" vent all the way up into the attic is fine, increasing to 2" or larger before it goes through the roof.

Your vent below the flood rim of the sink would not be allowed to fall less than 45 degrees and still meet code, and drilling the king studs for a 2" line is not a great idea. We would have to have engineering approval for steel support where the studs are compromised.

 

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[Terry]

Have you considered venting with an AAV?
Many kitchen sinks here are going that direction. Especially those on islands. It sure beats drilling the king studs.

 

[BRycraft]

View attachment 47875

Have you considered venting with an AAV?
Many kitchen sinks here are going that direction. Especially those on islands. It sure beats drilling the king studs.

I had considered it my first option but was told they are strictly prohibited in my town and should we ever sell it won't pass inspection. The other option I was given was loop back the vent in the floor to the vent the sink is currently connected to. Was told again not allowed.. This is why I came here, one plumber says drill thru the Studs the other says loop back, the only thing they agreed on is AAV is not to code where I live.

Ia it possible to bend around the studs with 1 1/2" then resize back to 2" so I limit the size pipe thru the back of the cabinets? like in this photo but reducing around the studs, why he went around two studs and thru 1 seems odd and should it still be sloped. What about the top plate? Thanks Bill

 

[Terry]

You only need 1.5" to vent a kitchen sink.
Most inspectors will allow a vent lower than 42" in that situation. The window prevents a normal situation.

 

[BRycraft]

I would run a 2" trap arm off the sink keeping it inside back of the cabinets until it is past the king studs, then into a new drain and vent stack in the wall. A 1-1/2" vent all the way up into the attic is fine, increasing to 2" or larger before it goes through the roof.

Your vent below the flood rim of the sink would not be allowed to fall less than 45 degrees and still meet code, and drilling the king studs for a 2" line is not a great idea. We would have to have engineering approval for steel support where the studs are compromised.

I am not quite following you about the less then 45 deg, between the sink and the vertical riser going thru the ceiling that can be horizontal? but it can't be sloped as much as I can to clear the window? I thought as long as it was sloped so any water that gets in the line can make its way to the drain unobstructed, seems a horizontal run would hold any such water?

 

[Reach4]

.I am going to place a kitchen island where the sink currently is and put in a small bar sink since the drain and supply are already there.

Did you understand cacher_chick's suggestion?

 

[BRycraft]

You only need 1.5" to vent a kitchen sink.
Most inspectors will allow a vent lower than 42" in that situation. The window prevents a normal situation.

Even with a total run of pipe vertical and horizontal about 30 feet? I just want to prevent any slow draining or gurgling from a vent that is at its limit?

 

[BRycraft]

Did you understand cacher_chick's suggestion?

I do I just don't understand the 45 deg comment, so I can run it on the outside the wall in the back of the cabinets but it can be horizontal from the from left to right as it passes over the studs but it can't have slope?

 

[Terry]

Most codes want to see the horizontal at 6" above flood. With a 36" cabinet, that would be 42".
Is your window preventing that? Most inspectors will still allow you to run it below the window. It depends on the inspector.
I normal bring the waste up to the side of the window for venting, and arm over. You can make an argument for either layout. Life isn't always perfect.

 

[BRycraft]

Yes my window is preventing that its 72" and a sink base of 36" on center if I had the drain and vent as far off to the side as possible it would be 18" closer to the side of the window but still 18" away from going straight up. Would running that piece on as much of an angle be better then going straight across and up?
Thanks Bill

 

[Reach4]

Yes my window is preventing that its 72" and a sink base of 36" on center if I had the drain and vent as far off to the side as possible it would be 18" closer to the side of the window but still 18" away from going straight up. Would running that piece on as much of an angle be better then going straight across and up?
Thanks Bill

The comment was that the vent should stay vertical until 42 inches above the floor, but 45 degrees is considered vertical for this case. However that does not help you here.

The solution proposed was that you put the santee just left of the king stud, come out of the wall with 2 inch, and go up to 4 ft (entire path) to the right under the window to the p-trap. That way the vent is to the left of the king stud.

 

[BRycraft]

I think I understand so I included a photo of what my interpretation of Cacher_Checks idea. My actual drain would be 43 inches from the center of my sink to the left. Being this is a slab and nothing has been broken up yet my options are still open. This would be possible as actually the supply lines that are currently servicing the island where my sink and dishwasher are currently positioned are directly in line, the drain isn't but past those water lines the drain does come in that services that island. Since I am looking to demo as much concrete as possible I will run the water lines with the drain pipe, however can I bring up those lines (PEX) and run them across the back wall over to the sink and install my shutoff there. Since this is a outside wall I can't install the lines inside them per code here. If this is the route when I run the pipe from the sink to the Sanitary T is a 90deg bend allowed because the pipe will be running parallel to the wall and needs to turn into the wall, whats the best solution?
Right now those service lines are copper coming up thru the floor. I will be breaking out in that area. I want to still service a new island with a small sink, can I tie into those water lines with pex using a T and then run the pex to the new sink location back under the slab?

Just thought this will be coming up right where my dishwasher will be located.. Could I still do this but not move the drain so far over to the right where I could run the vent on a 45deg angle and clear the window, would that be allowed, somewhere between in line with the king stud and sink so I can make that riser from sink to vent lay at 45 deg or more..?

Thanks for all the help. Bill

Something like this???

 

[Reach4]

I think I understand so I included a photo of what my interpretation of Cacher_Checks idea. My actual drain would be 43 inches from the center of my sink to the left.

If that became a problem, you could select a sink that has the drain on the left.

when I run the pipe from the sink to the Sanitary T is a 90deg bend allowed because the pipe will be running parallel to the wall and needs to turn into the wall, whats the best solution?

You can use a long sweep, and maybe a medium sweep.

Here is another possibility: bring the santee out of the wall and under the counter:

Below the concrete, the transition from vertical to horizontal for the drain should be a long sweep. That is where clogs tend to happen.

Just thought this will be coming up right where my dishwasher will be located.. Could I still do this but not move the drain so far over to the right where I could run the vent on a 45deg angle and clear the window, would that be allowed, somewhere between in line with the king stud and sink so I can make that riser from sink to vent lay at 45 deg or more..?

I am not following. Are you looking to go thru the studs?



Incidentally, I have read that PEX A (Aquapex etc) is more likely to survive a freeze. Any PEX is more likely to survive a freeze vs CPVC or copper.

 

[BRycraft]

No I am not looking to go thru studs if that violates any codes building or plumbing, especially if it weakens the structure. If code allowed it then I would have no problem but at this point I believe going around the stud is the best and safest option. Thanks so much for the help, greatly appreciated. Bill

 

[Cacher_Chick]

The entire sink drain line needs to be 2". The entire vent can be 1-1/2". A standard sink drain starts at 14- 15" above the floor, which leaves enough room for a deep sink with a disposal.
I an not clear as to why you would not run tbe drain and vent straight up and down to either the right or left of tbe window. The trap arm can be up to 4 feet long if need be to make it to the drain& vent stack.

If the inspector is following the code, you will not be permitted to run a vent on the horizontal below the window, unless it is at least 6" above the flood rim of the sink.

 

[BRycraft]

I am now planning on running the drain vent on the left side of the window and not drill thru any studs except the top plate.. I have a farm sink so its going to sit lower then a traditional sink. I am going to do as you suggested, place a sanitary T on the other side of the king studs and place the drain over there as well, then run a trap under the sink across the back wall into the sanitary T. Whats funny is currently my sink in its current location is on a island and the vent is about 3 feet away and they did the same thing ran the line after the trap into a sanitary t thats in the wall.. Never considered moving the drain vent over to the left until you suggested and Terry questioned me if I understood. I plan on doing what is in the
photo. this actually makes things a little easier because the drain running to the other side of the room will tie into the current 2" line feeding the 4 inch that runs to the main.. Whats a joke is if you look online all you see is people who drilled thru multiple king studs, horizontal runs etc.. SO first assumption is this must be ok because the window poses a problem and other people have worked around it... Then you find what they did was such a poor idea plumbing and building code wise explains why I rather find the correct info and do it myself. The one plumber was going to go thru those studs like it was nothing... This a professional licensed plumber, I just don't get it..

My only question regarding tying into the sanitary T from the sink how do I transition from horizontal to vertical into the sanitary T, what kind of transition piece can I use that doesn't obstruct water flow?
Thanks so much, this is why I ask those who are more knowledgable then myself.. Another reason I rather do thing myself, when we first moved in I hired someone to run a simple 120V line to service a hot tub in my back yard.. I didn't have the actual receptacle so the electrician rough wired it and left me to connect the outlet when it arrived, it was a special configuration plug but still 120V.. When I go to install it the guy NEVER RAN A GROUND WIRE... For a hot tub?, a hot tub and doesn't run a ground wire sounds like a disaster waiting to happen, this is when I decided if I can do it myself. Too many people taking short cuts but not at my expense anymore... Thanks Bill

 

[Reach4]

My only question regarding tying into the sanitary T from the sink how do I transition from horizontal to vertical into the sanitary T, what kind of transition piece can I use that doesn't obstruct water flow?

The sanitary tee transitions the flow from horizontal to vertical.

Another reason I rather do thing myself, when we first moved in I hired someone to run a simple 120V line to service a hot tub in my back yard.. I didn't have the actual receptacle so the electrician rough wired it and left me to connect the outlet when it arrived, it was a special configuration plug but still 120V.. When I go to install it the guy NEVER RAN A GROUND WIRE...

He may have run the wires in metal conduit, and if so, that acts as the ground wire.

 

[BRycraft]

No he unfortunately didn't, the plug from the hot tub was a GFCI plug, it required a ground wire back to the service panel to function safely.. Then he used blue and yellow wires, (WHAT), yellow is usually a switching wire and blue is generally travelers for 3 way wiring.. Maybe he didn't have black red or white IDK but shoddy work for a professional.. Like doctors someone had to be the worst who passed...lol

 

[Reach4]

I suggest you modify my sketch in #14 with your intentions.