Plumbing Vent Definitions & Distances
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Definition of plumbing vent terms, types of plumbing vents
How plumbing vent piping works
Plumbing vent piping distance requirements
Wet plumbing vents, dry plumbing vents, vent specifications
Plumbing vent clearance distances to building roof, vertical walls, nearby windows, or plumbing vent distance to chimneys
Questions & answers about plumbing vent piping and systems: code, installation, distances, sizes

This article defines plumbing vent system terms, distances, and functions, and other specifications and code requirements. We explain how plumbing vents work on buildings, why plumbing vent piping is needed, and what happens to the building drains when the vent piping is not working. We define the soil stack, waste stack, wet vents and dry vents, and we summarize the distances permitted between plumbing fixtures and their vent piping. We also explain how sewer gas odors m may be traced to plumbing vent problems.

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Plumbing Vent System Terms, Definitions, & Types of Vents

Our page top sketch of a plumbing stack vent and other sketches included below are provided courtesy of Carson Dunlop.

At PLUMBING DRAIN VENTS we explain the basics of proper plumbing vent piping and how errors cause trap siphonage, odors, and noises. We discuss how to diagnose and cure drain sounds at PLUMBING DRAIN NOISE DIAGNOSIS. Other advice about controlling plumbing noises in buildings is at SOUND CONTROL for PLUMBING. More details about plumbing drain line venting can be found at PLUMBING VENT DEFINITIONS & TYPES, also PLUMBING VENT DEFECTS & NOISES and at CLOGGED DRAIN DIAGNOSIS & REPAIR.

How & Why Building Plumbing Vent Piping Works

The plumbing vent system is part of the building plumbing drain system and serves two basic functions:

1. Allow building drains to flow freely by allowing air into the drain system, avoiding the vacuum and slow drainage that would otherwise occur at fixtures.

Imagine a full soda bottle with its cap off, turned upside down: the soda does not flow nicely out of the bottle. As some soda spills out, the spillage has to nearly stop to let some air into the bottle to fill the vacuum created by the soda leaving.

Now perform the same experiment, but punch a hole in the bottom of your soda bottle just before you turn it upside down. Because air can easily enter the bottle the soda flows nicely out of the bottle mouth.

2. Allow sewer gases to be vented safely outdoors. Because sewer gases may flow back up into the building drain piping from a public sewer or private septic system, and because some sewer gases are included in building waste flowing through the piping, the plumbing vent system needs to carry these gases outside, usually above the building roof, where they are disposed-of safely and without leaving unpleasant, or possibly dangerous smells and gases inside the building.

The basic plumbing vent terms are shown in the sketch at left. In these notes, the plumbing stack vents and other sketches included below are provided courtesy of Carson Dunlop.

What is the Plumbing Stack Vent?

Here we show the main building vent pipe, the plumbing stack vent, connecting inside plumbing drains to a vent pipe that extends above the building roof in order to let needed air into the drains and to vent sewer gases harmlessly above the building.

Below we explain how building plumbing vent systems work and why plumbing vents are needed for drain function and plumbing drain safety.

Above the roof plumbing vent height: vent pipes should extend to outdoors above the building roof and should terminate vertically not less than 6" above the roof surface (nor more than 24") and must be at least 12" from any vertical surface (such as a nearby sidewall). (UPC (i) 906.1 and 906.2). Note that there are other restrictions: for a roof that is also used as an occupied space, for example, the vent has to extend at least even feet above the surface and be secured with stays.

Above roof plumbing vent diameter: in areas exposed to snow or freezing or temperatures below 0 degF., that can block a plumbing vent, the vent pipe should be at least 2" in diameter beginning at least one foot inside the building in an insulated space before the vent passes through the roof. Where there is a snow-cover risk (snow can block the plumbing vent) the vent should extend 24" above the roof surface.

What is the Difference Between a Soil Stack & a Waste Stack?

The soil stack pipe, as shown in Carson Dunlop's sketch, carries waste from toilets to the house trap (if one is installed) and there connects to the sewer line extending outside the building and on to a public sewer or private septic system.

The soil stack is the large-diameter main vertical waste pipe or building drain, or vertical portion of the "main drain" in the building.

The soil stack pipe is normally extended outdoors above the building roof, as shown in the page top sketch.

Other main building drain piping sections that slope closer to horizontal are connected to the soil stack but move waste horizontally where needed in a building.

The waste stack pipe shown in the sketch refers to any other vertical drain piping in the building that does not carry soil (sewage) from a sanitary fixture (toilet). Typically waste stack piping carries drainage away from sinks, tubs, and showers.

How far can the plumbing vent piping be located from a plumbing fixture?

As we discuss at DRAIN NOISES, if the horizontal distance between a plumbing fixture and the vertical vent piping is too great, the fixture may not drain properly, producing slow drainage or gurgling noises.

Poor drainage is not just an annoyance, it can be unsafe since there is also the risk that the poorly-vented plumbing fixture will lose the water from its plumbing trap, then permitting sewer gases into the building.

As we show in Carson Dunlop's sketch, the distance allowed between a plumbing fixture (actually the fixture plumbing trap) and the vertical vent piping varies between a minimum and maximum as a function of the pipe diameter.

Tables of Plumbing Drain Pipe & Vent Pipe Sizes & Critical Distances to Plumbing Fixtures

Below our tables 1 and 2 summarize common plumbing code specifications for fixture venting and vent pipe sizes and distances that a plumbing fixture can be located (horizontally) from the vent stack. You'll see these distances also in our sketch at left. [Click any image to see an enlarged, detailed version.].

Table 1. Plumbing Drain Pipe Sizes
Drain Pipe Diameter	Vertical Drain Pipe, Maximum Number of Fixtures	Horizontal Drain, Maximum Number of Fixtures
1-1/4" dia	1	1
1-1/2" dia	2	1 (or 2 sinks)
2" diam	16	8
2-1/2" dia	32	14
3" diam	48	35
4" diam	256	216
Note: you can see from this table that at common home drain pipe sizes, if your pipe is 2" or larger you're unlikely to run into drain capacity trouble.

Table 2. Vent Pipe Distances
Drain Pipe Size	Vent Pipe Size[1]	Distance [2]
1-1/4" diam	1-1/4" diam	2-1/2 feet
1-1/2" diam	1-1/4" diam	3-1/2 feet
2" diam	1-1/2" diam	5 feet
3" diam	2" diam	6 feet
4" diam	3" diam	10 feet
[1] minimum diameter of the vent pipe [2] Critical distance between the plumbing fixture and the vent pipe. You can see that for vent pipe diameters under 4" you need to be vigilant about locating a plumbing fixture too far from its vent pipe/stack

Plumbing Vent Routing Specifications

Within the building the plumbing vent routing is generally unrestricted. That is, dry vent piping carrying only air, sewer gas, or moisture to above the roof line is unrestricted. However the piping does need to be protected from nails - use nail plates to protect vent and drain piping both where where piping passes through studs, joists, or rafters.

What is Direct Venting of Plumbing Fixtures?

Basically,larger piping diameter allows longer distances between a plumbing fixture and its vent stack. If a plumbing fixture is located too far from the main building vent stack, then its own drain pipe must have its own vent stack connection piping.

But if a plumbing fixture is close enough (five feet or less) to the main waste stack pipe (vent), the fixture does not usually require its own plumbing vent piping, and it is considered a direct-vented plumbing fixture.

Of course this rule presumes that the drain piping between the fixture trap and the waste stack is properly installed and properly sloped.

The usual slope on the fixture drain piping is 1/4" of slope per 12" (foot) of horizontal distance or "run" of piping.

What is a Wet Vented Plumbing Fixture?

In many buildings we find that the toilet is located quite close (within 5 feet) of the main building waste stack. This makes sense because the toilet needs really effective venting. Our sketch above shows a toilet located close to the waste stack - an installation that should work fine.

When you flush a toilet it sends a sudden large volume of waste and wastewater into the building drain waste vent (DWV) piping. This surge of wastewater can certainly create a vacuum problem in the waste line if the vent piping system is inadequate, blocked, or missing entirely.

It is exactly this condition that produces the gurgling or even siphonage out and loss of water in nearby sink or tub traps when you flush a toilet in a building where the vent piping is inadequate. See Plumbing Drain Noises.

A toilet that is located too far from the soil stack can be wet vented as shown in Carson Dunlop's sketch. The drain piping for a sink (basin) or other fixture located closer to the soil stack than is the toilet can provide a pathway to let air into the horizontal waste piping used by the toilet to carry waste to the soil stack.

But a wet vented fixture requires a larger drain pipe diameter in its wet portion as we show in the sketch. This diameter increase helps assure adequate air flow into the drain system in the event that the sink basin (in this example) happens to be draining at the same moment that the toilet is flushed. (908.2.3.)

Also note that wet vented fixtures (toilet, bathtub, shower, or floor drain) are permitted for bathrooms on the same floor level, not between floors.

Table of Plumbing Vent Clearance Distances to Building Features

The table below gives required clearance distances to various building features and cites pertinent model plumbing codes.

Building Feature	Required Distance from Plumbing Vent Termination to Building Feature	Comments
Roof Surface, distance to Plumbing Vent	6-inches above nearest roof surface	"nearest" accomodates sloped roof - i.e. measure from the "up-roof" side.
Nearest vertical surface, distance to plumbing vent	12-inches from nearest vertical surface	such as the side-wall of an upper story on the building
Nearest window, door, opening, air intake, or ventilation shaft: distance to plumbing vent.	10 ft (120-inches) from nearest window, measured horizontally - OR -2 ft. (24-inches) above nearest window [or other opening listed at left], measured vertically	We interpret this rule to apply to the required separation distances between a plumbing vent and nearest chimney on the building - Ed.
Distances are measured horizontally unless we indicate otherwise

Plumbing Code Citations for Plumbing Vent or Vent Stack Clearance Distances

Quoting model plumbing code such as the IRC:

12.4 VENT TERMINALS

12.4.1 Extension Above Roofs

Vent pipes shall terminate not less than 6 inches above the roof, measured from the highest point where the vent intersects the roof. EXCEPTION: Where a roof is used for any purpose other than weather protection, vents shall extend at least 7 feet above the roof and shall be properly supported.

12.4.4 Location of Vent Terminal

a. Vent terminals shall not be located where vapors can enter the building.

b. No vent terminal shall be located directly beneath any door, window, or other ventilating opening of a building or of another building, nor shall any such vent terminal be within 10 feet horizontally of such opening unless it is at least 2 feet above the top of such opening.

c. Where a vent terminal is within 10 feet horizontally and less than 2 feet above a ventilation opening described in Section 12.4.4b and the line-of-sight from the vent terminal to the ventilation opening is interrupted by the continuous ridge of a roof, the ridge shall be at least 2 feet above the top of the opening. Otherwise, the vent terminal shall comply with Section 12.4.4b.

d. Where a vent terminal is within 10 feet horizontally and less than 2 feet above a ventilation opening described in Section 12.4.4b and the line of sight from the vent terminal to such ventilation opening is interrupted by a solid wall or solid barrier, the top of the wall or barrier shall be at least 2 feet above the top of the ventilation opening and the shortest travel distance around the wall or barrier from the vent terminal to the nearest edge of the ventilation opening shall be at least 10 feet. Otherwise, the vent terminal shall comply with Section 12.4.4b.

Plumbing Code Citation References

International Code Council, 500 New Jersey Avenue, NW, 6th Floor, Washington, DC 20001 Tel: 1-888-ICC-SAFE (422-7233); Fax: (202) 783-2348 International: (202) 370-1800, Email: webmaster@iccsafe.org, Website: http://www.iccsafe.org
International Residential Code (IRC), for One and Two Family Dwellings, 2012 (First Printing)
Home Page: http://publicecodes.citation.com/icod/irc/index.htm
Citation Page:
http://publicecodes.citation.com/icod/irc/2012/icod_irc_2012_31_sec003.htm
International Mechanical Code (IMC), International Code Council [888] 422-7233, Op. Cit.
International Plumbing Code (IPC) (see NPC below), Op. Cit.
National Standard Plumbing Code, (NPC), 2009
obtained From: National Assoc. of Plumbing-Heating-Cooling Contractors in New Jersey at [800] 652-7422 or NAPHCC [800] 533-7694, [Cited by New Jersey State Department of Community Affairs]
http://www.state.nj.us/dca/divisions/codes/codreg/pdf_misc_codes/2006_nspc.pdf
New Jersey State Department of Community Affairs, Website: http://www.state.nj.us/dca/divisions/codes/codreg/

Frequently Asked Questions (FAQs) about plumbing vent installation, definitions, & clearance distances

Question: can the soil stack curve above ground to avoid a wall?

I am trying to find out if the soil stack can be curved above ground because there is a wall that I need to move. The wall will moved about 1 1/2 feet and the soil stack is currently inside the wall that I desire to move. This is in Portland, Oregon. The pipe that was used for the soil stack is cast iron, but I want to change this to the black ABS. Are there restrictions to how much the pipe can be curved? - Enan

Reply:

Take a look at the UPC (see citations in the article above or at "References" below. Certainly I've seen plenty of soil stacks (vent piping) that were not straight runs in above-ground (or above building) routing.

Because the above building vent pipe is venting sewer line gases and moisture, not liquids or solids, flow restrictions seem less likely a concern.

You might however want to look at the total above-ground run length vis-a-vis the vent pipe diameter because in a freezing climate a very long above-ground (above roof) length might increase the risk of freezing condensate and thus vent blockage in winter weather. In buildings I've examined I've not seen blockage in larger diameter vents at or above 2" but I've certainly seen it in smaller pipes.

Follow-Up comment:

Actually the part of the pipe that I wanted to curve would be down in the basement below the water closet (toilet, sink, and shower)There is only 1 restroom in this house. This means that the part that is curved would be under load from all the water draining from the sink, toilet, and shower. I was trying to avoid tearing up the concrete floor to install new drainage pipe and also because of how close the soil stack is to the cement wall in the basement. The basement is not a full basement, but about a quarter of it is still crawl space which has been framed, and drywall installed (its used for storage). The soil stack runs next to this wall that is half concrete half drywall. My plan was to cut the soil stack about three or four feet above the concrete floor and then do a 45 degree turn until the pipe enters the drywall portion of the partitioned wall and then have it go straight up to the roof. Do you know if that might cause a problem with the pipe being under load from the drainage of the water closet? I planned to change everything above the cut that I make into the cast iron pipe with ABS. Of course I would brace everything that needs to be braced.
Thanks.

Question: Can a sink and toilet share the same waste line and vent?

Can a sink and toilet share the same waste line and vent? - Jim

Reply: Yes but ...

Jim: yes vent piping can be shared, but all fixtures need to meet the distance requirements.

Question: drain trouble in a new house - bubbling lower floor toilet and slow drain

I just moved and seem to be having trouble with the drained in the new house. When someone is in the shower upstairs air bubbles come from the toilet downstairs. If you try to flush the downstairs toilet the water will not drain. Just wondering if anyone knows what the problem might be and what I can do about it. Thank you. - Lucas

Reply:

Lucas:

You may have a clogged building drain. Often a slow or partly blocked main drain line (or blocked septic system if you're not on sewer) can show up as bubbling and gurgling noises at fixtures lower in the building. Watch out for a sewage backup.

Question: one sink drains slowly and doesn't seem to clear - could it be a vent problem?

All the sink and tolets drain great in the house but one sink in the upstairs bed room. I have ran a snake, many times pipes are clean. Drain will handle water slowly. But if I fill the sink open the plunger or even take it out, it take an extremly amount of time to drain Could it be the dry vent if so, How Do I Clean it Thank you for you time. - Larry Miller

Reply:

Larry,

Indeed there could be a venting problem that leads to slow drainage but usually if that is the case for a given bathroom, in that bath, since usually all fixtures share a common vent, you'd expect to hear a glub glub sound when the drain is flowing, and flushing the toilet might produce noises at the sink drain. Maybe.

Depending on the lengths of drain, your snake may not have reached the blockage. Also sometimes a small diameter drain snake will pass right by a blockage but not make a sufficient opening to clear the drain.

If the drain used to work but has become worse, I suspect a crud/hair/soap scum blockage or if the house is old, and if drain piping is iron, perhaps rust clogging. I once paid an absurd sum to Plass the Plumber to "run a wire through a clogged drain" - a step that the plumber completed, got paid-for, and left. But his work did not help open the drain one iota. Later we began tearing open the wall to remove and replace galvanized iron drain piping. When I removed a short horizontal drain section in the wall between the sink and the main drain line, it was apparent that that section of piping was nearly 100% blocked by rust and iron deposits. The "wire snake" had just passed through that little opening but had not helped a bit. Really the only fix for that condition was to replace the piping. There was too much solid deposit to clear with a snake or with drain cleaner.

A more obscure vent problem that might leave the other fixtures draining OK could be found in a large bathroom at which the sink drain included its own vent pipe loop that eventually finds the main vent stack - and an odd coincidence of an insect or rodent blockage in just that vent - but frankly that's pretty unusual.

In sum I think you may want to pull the sink trap and try snaking with a rotary drain cleaner for a distance that leaves you sure that you've reached the main drain into which the other bathroom fixtures flow.

Follow-Up Comment: Derek Plumber offers more advice on clearing a blocked drain

A snake does not always completely clear a clog, blockage depending on how long it has taken to build up the blog, blockage can mean a difference in how you approach. Of course start with a snake the issue u have with it still draining slow is most likely that as you have gone through the clog, blockage and pulled the snake out that the Black Tar is just collapsing back on itself thus making it nearly impossible to clear with a snake.

If you have it draining slow this means that you have only cleared a path through the clog, blockage and that the issue is still there and will eventually blog up again.

You can try running your HOT water slowly while using your snake in a back and for motion many times over attempting to pushing what breaks free and is small enough for the water to push through ... a plunger will have little effect in forcing this down the drain.

This may or may not work.

Your best approach at this point, now that it will drain is to use a power flusher (you may be able to rent one)the hose is sized for the drainage pipe your working with, this works by spraying high pressure water usually min 1500 psi through the hose which has a variety of different heads attached to end. Id suggest using the head that has 3 holes spraying backward as it will help u by pushing itself through the pipe.

Make sure te hose is a good 3 feet in the pipe and u have a firm grip on it where it enters the clean out turn it on and run it slowly down back and start over till it is good and clear. - Derek Plumber

Question: how to move a toilet across the room - drain vent pipe distance trouble

I am trying to move a toilet 8 feet across a room, meaning that my venting pipe will be farther away than 5 feet. If I use the same soil stack, sloping the drain pipe 2 inches down over the 8 feet, do I need to add another vent stack pipe closer to the toilet to allow for air to escape, or can I allow the toilet to vent off of the existing vent stack? If I need to tap another vent stack into the line, any recommendations on how that needs to work?
Thanks! - Steve Strong

Reply:

Steve, if the toilet waste line is 4" or more ID, one of the sketches above, as I read it, says you can go up to 10 feet away from the soil stack. Make sure you have proper slope as well.

Question:

Can I have 3 toilets on 3 different floors conneted to the same vertical 3 inch soil pipe without separate vent pipes also added? Other wet vented fixtures are connected upstream from the toilet on the 2nd floor, which is the highest floor. - Larry Gatti

Reply:

Larry, yes; you will need to review DWV layout schematics in the model codes or training manual.

Question: definitions of discharge stack, waste stack, vent pipe

what is differentiate between discharge stack,waste stack and vent pipe. - Yana

Reply:

I take those terms to all refer to the vent pipe

Question: can water in the basement come from a leaky vent stack drain line?

When I have a heavy rain I have a puddle in the basement next to the bathroom drain pipes. This only happens during a heavy rain storm. Could I have a leak around the bathroom vent pipe? - Ray

Reply: yes but ... check these two other wet basement diagnosis clues

Ray, I have seen a few cases in which leaky vent stack flashing at the roof allowed water to run down the outside of a vertical plumbing vent stack pipe that in turn was enclosed in a chase-way that ran from roof to basement - water might indeed then show up in the basement.

But there are at least two other things to check:

Look for leaks into your sewer piping or backups that occur in flooding or very wet conditions.
Try inspecting your basement several times, with great care and a good flashlight during heavy rains. I have found that water can leak into a basement at a wall - say near a corner downspout that is not routed away or from roof gutters spilling over - then run across the basement floor to a low spot where water forms a puddle, leaving very little water along the path between the actual leak point and the puddle. If much time passes between the occurrence of the leak and the inspection, we may see only the puddle, and not the water track that leads back to its true source.

At BASEMENT LEAKS, INSPECT FOR we provide a series of inspection points useful for sure diagnosis of the cause of wet basement floors.

Question: how much clearance between plumbing vent discharge opening and top of brick chimney?

How much height clearance do I need between my plumbing vent discharge opening and the top of my brick chimney? Our vent pipe is located about 15 inches from the chimney. Chimney and vent are near the ridge (peak) of the roof. - Tim L.

Reply: Two feet or 24" is a code interpretation for distance between plumbing vent stack rooftop termination and the top of a chimney that is less than 3 ft. away.

Tim L - thank you for your question. I've reviewed and edited our section above on plumbing vent clearances to give code citations and details. I don't find chimneys explicitly named in plumbing vent sections of the model codes, but the distance to the "Nearest window, door, opening, air intake, or ventilation shaft" distance to plumbing vent needs to be 10 ft. horizontally OR the vent should terminate at least 24" (two feet) above the opening. I take this to include chimneys.

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PLUMBING VENT DEFECTS & NOISES

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Carson, Dunlop & Associates Ltd., 120 Carlton Street Suite 407, Toronto ON M5A 4K2. (416) 964-9415 1-800-268-7070 info@carsondunlop.com. Thanks to Alan Carson and Bob Dunlop, for permission to use illustrations from their publication, The Illustrated Home which illustrates construction details and building components. Carson Dunlop provides home inspection education including the ASHI-adopted Home Inspection Training Program (home study course), publications such as the Home Reference Book, report writing materials including the Horizon report writer, and home inspection services. Alan Carson is a past president of ASHI, the American Society of Home Inspectors.
International Code Council, 500 New Jersey Avenue, NW, 6th Floor, Washington, DC 20001 Tel: 1-888-ICC-SAFE (422-7233); Fax: (202) 783-2348 International: (202) 370-1800, Email: webmaster@iccsafe.org, Website: http://www.iccsafe.org
International Residential Code (IRC), for One and Two Family Dwellings, 2012 (First Printing)
Home Page: http://publicecodes.citation.com/icod/irc/index.htm
Citation Page:
http://publicecodes.citation.com/icod/irc/2012/icod_irc_2012_31_sec003.htm
International Mechanical Code (IMC), International Code Council [888] 422-7233, Op. Cit.
International Plumbing Code (IPC) (see NPC below), Op. Cit.
National Standard Plumbing Code, (NPC), 2009
obtained From: National Assoc. of Plumbing-Heating-Cooling Contractors in New Jersey at [800] 652-7422 or NAPHCC [800] 533-7694, [Cited by New Jersey State Department of Community Affairs]
http://www.state.nj.us/dca/divisions/codes/codreg/pdf_misc_codes/2006_nspc.pdf
New Jersey State Department of Community Affairs, Website: http://www.state.nj.us/dca/divisions/codes/codreg/

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The Home Reference Book - the Encyclopedia of Homes, Carson Dunlop & Associates, Toronto, Ontario, 2010, $69.00 U.S., is available from Carson Dunlop. The Home Reference Book is a bound volume of more than 450 illustrated pages that assist home inspectors and home owners in the inspection and detection of problems on buildings. The text is intended as a reference guide to help building owners operate and maintain their home effectively. InspectAPedia.com ^® author/editor Daniel Friedman is a contributing author. Field inspection worksheets are included at the back of the volume.

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Plumbing Vent System Terms, Definitions, & Types of Vents

How & Why Building Plumbing Vent Piping Works

What is the Plumbing Stack Vent?

What is the Difference Between a Soil Stack & a Waste Stack?

How far can the plumbing vent piping be located from a plumbing fixture?

Tables of Plumbing Drain Pipe & Vent Pipe Sizes & Critical Distances to Plumbing Fixtures

Plumbing Vent Routing Specifications

What is Direct Venting of Plumbing Fixtures?

What is a Wet Vented Plumbing Fixture?

Table of Plumbing Vent Clearance Distances to Building Features

Building Feature

Required Distance from Plumbing Vent Termination to Building Feature

Comments

Plumbing Code Citations for Plumbing Vent or Vent Stack Clearance Distances

Plumbing Code Citation References

Frequently Asked Questions (FAQs) about plumbing vent installation, definitions, & clearance distances

Question: can the soil stack curve above ground to avoid a wall?

Reply:

Question: Can a sink and toilet share the same waste line and vent?

Reply: Yes but ...

Question: drain trouble in a new house - bubbling lower floor toilet and slow drain

Reply:

Question: one sink drains slowly and doesn't seem to clear - could it be a vent problem?

Reply:

Follow-Up Comment: Derek Plumber offers more advice on clearing a blocked drain

Question: how to move a toilet across the room - drain vent pipe distance trouble

Reply:

Question:

Reply:

Question: definitions of discharge stack, waste stack, vent pipe

Reply:

Question: can water in the basement come from a leaky vent stack drain line?

Reply: yes but ... check these two other wet basement diagnosis clues

Question: how much clearance between plumbing vent discharge opening and top of brick chimney?

Reply: Two feet or 24" is a code interpretation for distance between plumbing vent stack rooftop termination and the top of a chimney that is less than 3 ft. away.

Questions & Answers regarding this article

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Books & Articles on Building & Environmental Inspection, Testing, Diagnosis, & Repair