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PLUMBING VENTILATION: WHAT IS IT AND HOW DO I KNOW IF IT’S WORKING?


plumber doing maintenance work for sink pipes

Most homeowners know that every toilet, sink, shower, dishwasher and washing machine has a drain to carry dirty water away. However, what many don’t know is that ventilation is also an integral part of their plumbing system. Here’s the lowdown on plumbing ventilation and how to tell if yours isn’t working.

What is plumbing ventilation?


Plumbing ventilation helps to regulate the air pressure in your plumbing. Each drain in your home should have a ventilation pipe that connects to the vent stack on your roof. This system plays two important roles:

  1. To help water drain efficiently. Proper airflow is an important aspect of efficient plumbing. Think of pouring liquid from a can. With one small hole, the liquid won’t come out evenly. Putting a second hole opposite the first lets air come in to replace the liquid, allowing it to pour out smoothly.

  2. To stop harmful gases from building up. Each fixture has a P-trap that holds a small amount of water that stops noxious fumes from escaping into your home. Without a vent, this water would be siphoned out completely and replaced with sewer gases.


Signs your plumbing isn’t vented properly

If you notice any of the following issues, your ventilation lines may be clogged or have another issue.

  • Gurgling sounds. These noises can occur when air is unable to escape the pipes as it normally would.

  • Sewer odours. Poor or clogged ventilation may cause P-traps to empty and release harmful gases into your home.

  • Bubbles in the toilet bowl. If drain pipes struggle to get enough air to equalize the pressure within, bubbles might form in the standing water in your toilet.

  • Fluctuating water levels in the toilet. Without enough pressure in the pipes, water in the toilet can rise and fall suddenly or be drained away completely.

  • Clogs that can’t be cleared. If a clogged drain remain sluggish after repeated attempts to clear it, the venting could be at fault.

If you think you have an issue with your plumbing ventilation, it’s important to get it looked at by a professional. Plumbing ventilation isn’t something that can be repaired by the average homeowner.

Plumbing Help in Southwestern Ontario


The pros at Pitton Plumbing & Heating are equipped to handle virtually any residential, commercial or emergency plumbing issue you have. Call us to schedule a visit from a plumber today. We serve Hamilton, Burlington, Toronto and most parts of Southwestern Ontario.

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