Plumbing Vents & Your Roof: Potential Problems

Plumbing Vents & Your Roof: Potential Problems

A plumbing vent is one of the least noticed yet most important parts of a residential plumbing system. While you may see them up on rooftops (along with attic vents and chimneys) — typically plumbing vents just look like narrow tubes pointing into the air.

Your plumbing system needs two important things in order to work: 1. A place to release sewer gases, and 2. A place to bring in oxygen. Plumbing vents provide both at the same time. When sewer gases build up in pipes, those gases naturally rise. The gases are then released near your roof (where no one can smell them). What would happen if the gases weren’t released? Those gases would block and damage pipes, rendering your plumbing unusable. The “stack” or pipe that leads up to your roof also draws in air for a similar reason: Your sewer system needs help breaking down waste. Your pipes need air to maintain a neutral pressure that allows water to flow properly through your home.

Not everyone has a plumbing stack (there are alternative vents for releasing gases). In addition, not everyone has a one located on their rooftop—however they are still very common. In fact, they are so common that chances are if you went outside and searched your roof right now, you would find one.

Do Plumbing Vents Need Maintenance?

Most of the time, plumbing vents do not require maintenance. They have a simple job that doesn’t need much attention. The big exception to this rule occurs in the event of a plumbing vent clog. Because these vents are often open to air and not very far up from the roof surface— they can get clogged a number of ways. Common clogging culprits include:

  • Debris: Leaf and dirt buildup can clog plumbing vents (especially in fall or if there are trees nearby).
  • Bird nests: Smaller birds will build their new nests in plumbing vents sometimes. This block can cause a clog.
  • Snow and ice: If too much snow builds up around your roof, the snow could cover up the plumbing vent.
  • Dead animals: This is unpleasantly common, as both rodents and birds may go exploring in your pipe. If they get trapped and die there, they’ll block the pipe so that gases cannot easily pass.
  • Random objects: This is less common, but sometimes bits of construction materials and other objects can become lodged in your pipe.

Plumbing Vent Problems: What Are The Signs?

Signs of a clog are similar to signs of a sewer system problem. Your pipes may make strange sounds, and your drains will not be reliable. Sinks, showers and tubs may take a long time to drain even if you can’t find a clog, or they may bubble with stinky sewer gases at odd times.

Keep in mind that clogs can occur throughout plumbing vents, so just climbing on your roof and looking down the stack won’t always help you locate the problem. Professionals use inspection cameras, drain snakes, and a number of other specialized tools to find and remove clogs. Hire someone who knows how to properly climb around your roof. They’ll have a much better chance of fixing the plumbing vent problem without causing any new damage!

Photo Source: Flickr

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