When you think of clogged plumbing, blockages in drain pipes are probably the first issue that comes to mind. But there’s another part of your plumbing system that can become blocked: your sewer vents. Located on the roof, these vent pipes allow gases to escape from your sewer system. They regulate the air pressure in your system, allowing waste to flow freely. If they become blocked, your system won’t drain properly. Here’s a closer look at this issue.
Signs That Your Sewer Vents Are Blocked
The signs of a blocked sewer vent often mimic those of a blockage in the drain pipe. For this reason, some cases of blocked vents go undiagnosed for months or years while the homeowners try DIY fixes to clear drain lines-but to no avail. The following are common signs that your sewer vents could be blocked.
You may hear gurgling or even see water bubbling up and out of the drains as they drain. You may also hear gurgling coming from your toilet shortly after you flush. The gurgling is caused by air escaping through the drain. The air should be flowing up and out of the sewer vents, but since they are blocked, it has nowhere else to escape but through the drains.
Note that in some cases, you may hear gurgling in drains other than the one you’re using at the moment. For example, if you flush a toilet, you may hear gurgling in the tub. This indicates that these two plumbing fixtures share a vent-and it is blocked. In some cases, gurgling noises indicate that there is no vent for that particular drain or fixture.
A single slow drain usually indicates a blockage in the drain itself. And slow drains can certainly be an indication that there’s something clogging your main sewer pipe. However, if all of the drains in your home are slow and you’re also noticing the other issues described in this section, blocked sewer vents are more likely to blame.
The air emitted from your sewer lines doesn’t smell like a bed of roses! If you notice sewage odors coming from your drains and toilets, but you don’t see any overt sewage backups or spills, what you’re probably smelling is the air escaping through the drains.
Causes of Blocked Sewer Vents and Their Solutions
There are a number of possible causes of blocked sewer vents. These three are the most common.
If you started to experience the problems described above after a snowstorm, snow on the roof is probably blocking your sewer vent. This is most likely to occur on a flat roof, from which the snow does not drain properly, or after a really heavy snowstorm that results in several feet of snow on the roof.
In the short-term, your plumber can fix the issue by clearing snow away from the vent and melting any snow that has made its way down inside of the vent. However, to prevent this issue from occurring again, they’ll also want to replace your vent pipe with a longer one that extends above the level of snow on your roof.
Your plumbing vent should be angled at the end to prevent leaves and other debris from making their way into it. If your sewer vent is filled with debris, your plumber may remove it using a special grabbing tool. Then, the vent pipe may be re-angled and a new cap may be put into place to keep debris from clogging it again.
There may be a clog in the sewer line right where it meets the vent pipe. This blockage keeps air from traveling up the vent pipe properly. Sometimes, these clogs comprise materials like wet wipes and feminine hygiene products, which homeowners commonly flush even though they are really not designed to go down the drain.
This kind of blockage is the hardest to remove. Your plumber may need to access the blockage through the vent on the roof, pushing a plumbing auger down through the system to grab onto the offending material and pull it out. In the future, sticking to flushing only human waste and toilet paper will keep you from dealing with the same problem again.
If you’re having trouble with slow drains and sewer odors, and plunging your drains has not fixed the issue, then it’s definitely time to call Jim Dhamer Plumbing. Whether the blockage truly is in your vent pipes or in your main sewer line, it’s important to deal with it promptly before it results in raw sewage or smelly air flowing into your home.