NC Plumbing Code - Administration

Chapter 1: Scope and Administration

Much of this chapter has moved to another book – North Carolina Administrative Code andPolicies – which should be studied in addition to the Plumbing Code. What is left is general requirements for existing structures, temporary facilities, repair, and remodeling. There is also a section on inspection and jurisdiction.

It often comes into question, “What requires a permit, and what should be inspected?” Those requirements are addressed in this section.

All new construction and additions to existing plumbing systems require a permit and inspections. Some minor repairs and replacements can be completed without a permit, but they are very limited. You can, for example, change out an existing fixture, such as a faucet or toilet, without permit or inspection. You can even replace a water heater if it is the same size and fuel source, but not if the piping needs to be rerouted – so if you are moving the heater to the other side of the laundry room or closet you need a permit.

The basic rule is – you can replace piping and appurtenances exactly as they exist, but if the system must be altered then a permit and inspection is required.

The code also touches on historical structures and new innovation. Since historical structures must remain as they were constructed for historic purposes, the code allows for replacement and repair by historic methods that may now be prohibited by code. It also allows for special engineered designs that may allow new innovations of materials and methods. In all of these special cases a great deal of latitude is given to the local code official to use discretion.

This brings up a point that runs throughout the code – local rulings and the authority of the local inspector. The local inspector is expected to interpret and arbitrate the written code along with possible local ordinances or accepted practices. There may be requirements imposed by the local health department, for example, or minimum standards for a specific type of building. Much is left to the inspectors discretion when performing inspections.

It is always a good idea to check with the local official on anything that doesn't seem clear in the code. It never hurts to ask a question.

If you are working toward your journeyman or technician license there will be less emphasis on administration and more on piping systems on the test. But it is still important to understand the laws and regulations that must be followed. If you are working toward a state contractors or “Masters” license you will need a copy of North Carolina Administrative Code and Policies. In either case there will be questions on administration.

HB2 - Simple Solutions

The battle for bathrooms rages on. It has drawn national attention and cost a sitting Governor his re-election. And even as North Carolina is ranked in the top five states economically the media bewails the “millions of dollars” HB2 has cost the state economy – from basketball tournaments to rock concerts. But let's have a more serious look.

The Charlotte ordinance which prompted HB2 required businesses to allow transgender individuals access to facilities based on the gender they “identify” with. The law applied to public and private facilities, including schools. We are not only talking about individual toilet rooms or changing rooms at Target with latching doors. The rule applied to open “gang” showers and locker rooms.

In modern western culture we have developed the idea of personal modesty and privacy. That is the reason large public bathrooms have stalls and doors. If a man or woman exposes themselves to a member of the opposite sex it is considered a crime. There are cultures where such puritan ethics are unheard of and public bathing is not an issue, but not in western culture. There are also cultures where rape is not considered taboo.

That is the problem with Charlotte's ordinance and the reaction of the State in HB2. Supporters of HB2 have failed to present that basic, and simple, argument. They have allowed outside forces and liberal politicians to frame the case as “homophobia” and bigotry against a growing LGBTQ community. But the truth is more complicated. The Charlotte ordinance was bigoted against those who desire a degree of privacy and modesty.

If you asked the question “Are you okay with having a male in the shower with your daughter?” the answer would be almost unanimously NO. The person's “gender identity” is not really relevant when everyone is naked. What is relevant is young men and women being presented with the genitalia of the opposite sex in places like locker rooms and gang showers where they are required to disrobe. What is at issue is privacy and modesty.

This is an easy problem to fix that doesn't require either side to give up their rights. We do not need to force members of one biological sex to be in close proximity with the opposite biological sex while both are exposed. Remember, we put stalls with doors in bathrooms so we don't even have to expose ourselves to members of our own sex while we take care of business.

I remember when I was a kid many public restrooms had long trough urinals where men would crowd in, shoulder to shoulder. They were deemed unsanitary, and men wanted a little more privacy, so today we have individual urinals with partitions between them. Many facilities have done the same with showers, though many schools still have large, open, gang showers. But we have never had unisex gang bathrooms or public bath houses where men and women share facilities.

The simple fix is more privacy, not less. Just like the case where the state code requires division between urinals, a move to individual facilities would solve the problem without injuring the sensibilities or rights of either side. It is a design problem, not a political one. Trans people do not want to use the facilities of the gender they do not identify with and many non-trans people do not want to expose themselves with those of a different biological sex. Individual facilities do not require gender distinction.

This is where my whole rant relates to the plumbing industry, which is the point of this blog. We can design facilities that are more private and thereby more inclusive without stepping on anyone's toes. The cost may be slightly more, but not unreasonable if facilities are properly designed. I'm sure there was some complaint from business when trough urinals were phased out. But the payback in customer satisfaction, and saving expensive remodeling later with the whim of politics, is worth a little redesign.

It is up to us as plumbing professionals and designers to solve this issue. We should lead the way and make the battle over bathroom bills a non-issue. Some simple measures could be having partitions extend floor to ceiling with lockable doors, partitions in locker rooms, and individual shower rooms with adjoining changing areas. All of these exist in some facilities, it's just a matter of standards.

If our designs look at the places people demand privacy, and provide that privacy, we can make facilities that are more open and more private at the same time. A large unisex facility could have individual toilets and showers with individual changing rooms yet a large common area of lavatories and lockers. No one's privacy would be intruded, but there would be more inclusion and possibly a savings in construction and maintenance costs.

When we look to solve problems, not posture on ideology, we can find efficient, progressive answers. The “Bathroom Bill” debate is more about posturing than solving problems. As the nations designers and builders we can fix this. As America's plumbers, this is our arena – our area of expertise. Leave bathrooms to the State Board and to plumbers, not legislators and pundits. North Carolina can lead the way. Plumbers can once again “protect the health of the nation.”

Vents and Venting 101

When I talk to people in the industry – plumbers, designers, and engineers – I find a lot of confusion surrounding proper venting techniques. Venting in a piping system is based on one simple principle. If you place a drinking straw in a glass of water, then place your finger over the end of the straw and remove it, the straw stays filled with water. The water in the straw cannot flow out until air is allowed in. The straw is air-locked.

In a piping system, as fluid flows through the pipe, air is pushed ahead of the fluid and air must enter the system behind the fluid. This creates pressure changes in the system with pressure ahead of the flow increasing and pressure behind the flow decreasing. In a closed system the flow would stop, as it does in the straw. In an improperly vented plumbing system the flow is restricted, pressure on downstream traps can cause sewer gasses to push through, and negative pressure on upstream traps can siphon them dry. The restricted flow can also cause stoppages.

The principles behind proper venting allow these pressure changes to be eliminated. The most basic and effective vent system would be to individually vent every fixture in the system, and some engineers use this configuration for its simplicity. But this is lazy design and adds unnecessary piping which in turn adds cost to the customer. It is not necessary to individually vent every fixture in order to create a fully functional vent system. With a little thought, vents and their related cost can be eliminated without changing the effectiveness of the system.

Two of the chief confusions I find comes from terminology used and proper application of principles. I will focus on three main concepts that represent the same basic principle and seems to create the most confusion – Wet Vents, Circuit Vents, and Loop Vents. Keep in mind our guiding principle – fluid flowing in a pipe creates pressure fluctuations. We want to limit those fluctuations and allow air to freely enter and exit the system to keep the fluids flowing.

Circuit Vents and Loop Vents are in essence the same thing. In both cases a vent is extended up from the horizontal piping between the last two fixtures on a branch in order to vent a group of fixtures. The only difference is where the vent terminates. In a Loop Vent the vent loops back to the Stack Vent. This is only possible on a stack with one branch interval or the topmost interval of a multi-interval stack. Circuit Vents terminate individually or tie into a vent stack or vent header.

Loop Venting has advantages over Circuit Venting as it creates a relief vented loop with a vent before the first fixture on the branch (the Stack Vent) and a vent before the last fixture on the branch which are then tied together providing circular air flow within the branch. We will discuss relief venting later. In the Circuit vent we are limited to a single vent to provide air to our system. Yet often that is all we need.

In a Circuit Vent, as in a Loop Vent, the horizontal branch line is vented, providing a common vent for all fixtures connected to the branch. This eliminates the need for individual vents. We are limited to eight total fixtures on the branch, and only four can be water closets unless we add another vent before the first fixture – a Relief Vent. With the relief vent, or with a Loop Vent (which provides its own relief vent) we can vent up to eight water closets. That eliminates up to seven individual vents!

We can also connect multiple circuit vented branches in series, so in essence we only need one vertical vent for every eight fixtures on the horizontal branch (Remember: only four can be water closets unless we relief vent). In applications such as gang toilets or gang showers the cost savings for the customer really add up. And we are still providing ample air flow to our system. The principle behind this technique is based on the physics of fluid flowing in the pipes. In a properly sized and graded horizontal drain line (the grade on a circuit or loop vented drain should be no more than 1:12) the fluid stays in the lower half of the pipe, leaving air in the top half. This allows the drain itself to partially act as a vent.

That brings us to the Wet Vent. A wet vent is simply a vent that is also used as a waste for another fixture – generally a lavatory or sink drain. In a bathroom group, or two adjacent bathroom groups, all of the fixtures can be vented through the lavatories as a wet vent. This configuration is very much like the Circuit or Loop Vent – the fixtures on the horizontal branch are commonly vented through the waste riser serving the lavatories – but the wet vent can be the last fixture on the branch. It is also permissible in Circuit Vents and Loop Vents to utilize a Wet Vent for any or all of the required vents or relief vents mentioned previously.

A Wet Vent can also be used to vent another fixture as a Common Vent, such as venting a floor drain with a lavatory drain. Also, one fixture above another on a stack, such as a sink connected above a washing machine or a lavatory above a water cooler, can act as a wet vent for the lower fixture. We can even stack fixtures floor-to-floor, such as hand sinks or mop basins on multiple floors connected to a single vented waste stack. There are of course restrictions to what fixture drains can serve as wet vents, and pipe sizes required, but often one vent can serve multiple fixtures and thereby lower costs and complexity of the plumbing system.

Proper venting is not that complicated when we keep the basic principle of pressure changes in mind and follow the simple sizing and maximum fixture loads spelled out (with charts!) in the NC Plumbing Code. And when in doubt, an extra vent here or there will not hurt anything. You cannot over vent, but you can waste the customer's money by adding unneeded vents. The balance we seek is adequate air flow with minimum vent piping for the most efficient design and installation.

A few points to keep in mind:

• Eight fixtures on a single branch (no more than four water closets) can be vented with a single vent located between the last two fixtures on the branch – Circuit Vent
• More than four water closets on a branch requires a relief vent before the first fixture on the branch – Circuit Vent or Loop Vent
• A Loop Vent is, in essence, a Circuit Vent tied back into the branch's relief vent (Stack Vent)
• A Wet Vent is a vent that receives discharge from another fixture
• A Wet Vent can be used to vent two complete bathroom groups
• A Wet Vent can be used as the vent and/or the relief vent on a Circuit or Loop Vented branch
• Multiple fixtures can drain into a single, properly vented stack

A few “Gotchas” in Mecklenburg County:

• Urinals on a Circuit or Loop Vented line should tie-in to the branch on the horizontal and cannot be used as a Wet Vent
• Fixtures downstream of a water closet must be individually vented (some inspectors allow floor drains on a Circuit Vent with water closets – but better to individual/common vent and be safe)
• Pumped lines, such as a washing machine drain, cannot be used as a wet vent. Some inspectors consider a dishwasher to be a pump discharge – or a pump from an icemaker or condensate line.

In closing; I would suggest a quick reading of the NC Plumbing Code, Chapter 9 – Vents. It is very clear on when and where vents should be placed. I will also suggest a quick Google Image Search of Circuit Vent. As I said at the beginning, much of the confusion seems to stem from the terminology. There is very little difference between Circuit, Loop, and Wet Vents. They are all based on the same principles.