Drainage in residential and commercial structures adheres to the same principle: gravity is utilized for pulling wastewater along drain pipes into the municipal septic tank or sewer system. This is unlike water supply systems that need the pressure to get the water into a building. Drain pipes are slanted downward to allow the removal of water through the force of gravity. Plumbing wet vents allow the natural pressure in pipes to equalize and push wastewater and other material along. Without the push added by wet vents in the drainage pipes, you would have to siphon water or remove it artificially.
What Is a Wet Vent?
While many think installing a wet vent is all about quick ventilation concerning bad smells, venting is not that simple. The process is complex and directly connected with sewer and plumbing pipes. As you may be aware, atmospheric pressure impacts all things on earth, which includes our toilets. The pressure should be balanced in waste pipes to enable the appropriate work of sewerage and water supply systems.
Wet vent plumbing has been in practice since 1920 when the first plumbing code was established. But, it has only recently been added by the Uniform Plumbing Code to the plumbing code. Due to this, people have difficulty understanding wet vents and how they work. A wet vent is officially defined as a pipe serving simultaneously as a waste pipe and vent. Also, the wet vent protects the drain’s trap for other fixtures connected to the system.
If you are not aware, every bathroom fixture needs venting. If a fixture does not have a vent, it could lead to several problems such as slow water draining, gurgling noises, unpleasant odors, and emission of methane gas, which poses a health risk for your family.
Dry Vent vs. Wet Vent
How does a wet vent differ from a dry vent? A wet plumbing vent drains water from one fixture while ventilating the air, among other fixtures. On the other hand, a dry vent only transports air and does not carry water. This is to say that wet vents may drain one fixture and vent another, whereas dry vents typically vent air from a single fixture at a time. Many choose wet vent plumbing systems because they save money, time, and materials. For instance, when adding a new bathroom to your home, it can be a hassle to build a new drain line, especially if a closet is on the way.
Wet Vent Codes and Rules
You should be aware of the following codes and rules when installing wet venting. It is essential to remember that codes vary by state and city. The guidelines below are universal to both Canada and the United States.
While wet plumbing vents are better for two or more bathroom fixtures simultaneously, all the fixtures should be on the same floor. They cannot be installed on separate floors.
When connecting a toilet in the wet vent system, the toilet should be lower than other fixtures utilizing the same vent. This rule has no exceptions.
Install a pipe supporter in every 4 feet of straight plastic pipe. The clips ensure secure holding of your pipes and help for abnormal pipe configurations. Most professionals like Proactive Comfort recommend using economical plastic pipe-hanging straps with roofing nails.
You can install wet vents to your preferred length, but most building codes have a recommended minimum size for wet vents. This is because extremely short pipes may cause a hydraulic overload. Ensure that you check your local plumbing codes before starting your project.
The angle connecting the wet vent to the horizontal drain is specified. The vent should connect to the drain line at an angle of at least 45 degrees. Ensure that pipes are the correct size. The size of the pipes determines the amount of hydraulic load they can hold.
It is essential to ensure that your wet vent pipe is large enough to prevent unnecessary problems. A small wet vent can cause leaks, hydraulic overload, clogging, and other problems. If you’re in doubt, use a 3-inch wet vent and a 4-inch waste line pipe. If you adhere to these rules, your plumbing system will pass inspection and function properly for many years.
Signs of Poor Wet Venting
Poor venting on drain lines leads to ineffective movement of wastewater and solid waste from a building. This could result in backed-up toilets, overflowing drains, and plumbing issues. Rectifying the issue may only involve unclogging the drain line. However, it could also need more substantial work to locate and fix drain lines. Consult Proactive Comfort for advice and professional services.
This is among the most evident sign of a poorly done wet vent. If wastewater moves slowly from bathroom sinks or bathtub drains, the problem could be associated with inadequate or improper venting. If your bathroom drains are emptying slowly, it may also be because of a blockage or clog along the drain line. Before implementing other significant measures to rectify the problem with wet vents and slow draining, ensure that you exhaust all other avenues for resolving a slow-moving drain.
Usually, noise should not accompany drainage. So, any sound emanating from your drain lines could indicate poor ventilation. It may indicate a venting problem if you hear gurgling sounds from your toilets or bathroom sink drains. The sound is produced when there is restricted airflow in pipes, making it difficult for wastewater and material to move within the drain pipes.
Bubbles in the Toilet Bowl
If you notice bubbles in the water in a toilet bowl, it could mean a venting problem. The bubbles usually form as the pipes try to obtain sufficient air to balance internal pressure.
Toilet and sink drains have a trap holding small amounts of water after draining the toilet or sink. The water creates a seal that stops odors and gases from leaving the drain system and accessing your home, creating unpleasant smells. If the air pressure from the vent is insufficient, the water can be lost. When these traps go dry, sewer odors won’t have anything blocking them from escaping into your home’s interior.
Empty Toilet Bowls
If your toilet bowl does not refill after flushing or the water level in the tank or bowl falls or rises suddenly, it could mean venting issues in the drain. If there’s insufficient pressure in the drains, water in the tank or toilet bowl may flow away, resulting in inconsistent water levels.
Your Local Expert Plumbing Company
When doing wet vent plumbing, you should strictly follow the codes and rules regarding wet vent installation. Therefore, you should carefully review and follow them in detail. Failure to do this will lead to your project not being approved by your local plumbing inspector. You may be asked to redo it, which is expensive and bothersome. Save yourself this frustration and allow Proactive Comfort to do your wet venting project.
At Proactive Comfort, Nashua, NH, our highly trained and licensed technicians and plumbers have the knowledge and experience to keep your plumbing, air conditioning, and heating operating flawlessly. Call our office today, and we will be glad to be of assistance.