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What You Can Do When Your Basement Smells Bad

Have you got a foul odour coming from your basement? There are several potential causes of foul odours in the basement or anywhere in your home, especially where plumbing could be a factor. Mold, drainage problems, sewage, pests, leaks, and rust are all potential culprits for a bad-smelling basement. Before you can do anything about it, you need to identify the source.

There are some quick fixes to bad basement smells that can provide temporary relief, but to really conquer basement odours, you need to find and fix the source of the problem.


1: Pests

Pests are a common source of bad odours in the basements. The smell could be coming from waste left by rodents or bugs, or even from the body of a dead rodent hidden behind a wall or in a corner of your basement. If you can’t locate the smell, an exterminator should know how to find it, as well as how to deal with the problem.

While an odour coming from pests isn’t something your plumber can deal with, rodents often find their way into their home around your plumbing. Do an inspection around the outside of your home (or have a qualified exterminator identify like access points for rodents). To prevent any further intrusions from rodents and bugs, seal up gaps around pipes and drains.

You can use caulk to seal up smaller gaps to keep out insects. Unfortunately, mice and rats will still be able to gnaw their way through caulk and expanding foam. You can stuff steel wool into the gaps with a screwdriver to protect against rodent intrusions.

For larger gaps, you may need to use welded wire trimmed to fit the space or a flexible metal screen to fit around oddly-shaped entry points. Remember that while many gaps are the result of the construction, leaks and water damage can also soften building materials and create entry points, so keep your drains and pipes in good condition and check once in a while for leaks.


2: Mold or Mildew

Mold and mildew are among the most common reasons for funky smells in the basement. Mold may form somewhere visible, but it can also grow in wall cavities, above ceilings, or even in carpets, which can make it difficult to track down.

Mold is the growth of unchecked bacteria. It’s caused by stagnant moisture, often the result of a leaky pipe, condensation, or exposure to the outdoors. Leaky pipes are often to blame for the growth of mold.

If you’ve identified a mold problem due to a leak, call the Sewer Squad for drain repair or replacement — we are your local plumbing experts in the GTA. Many pipes in the GTA are over half-a-century old. They break and corrode over time, and that causes damage to your home. With cold winter temperatures, pipes can also freeze and burst.

Once you’ve fixed your leak, you’ll need to remove the mold to fix the smell. There are different methods to remove mold from different materials like drywall, wood, carpet, or tiles and grout:

Drywall: You will have to cut away sections of drywall with mold on it. If you remove the drywall between two beams, it will be easier to replace. If it’s on painted drywall, you won’t have to replace it, just scrub the mold off using bleach, borax, vinegar, hydrogen peroxide, or another appropriate cleaning material.

Wood: You can usually keep wood after it has been cleaned up. Simply scrub the mold off with a wood-friendly cleaning agent and a sponge or a scrubbing bush. It may leave a mold stain, which shouldn’t regrow if you’ve scrubbed the mold away and fixed the issue, but it can be a cosmetic issue. You can sand away mold stains.

Carpet: Unfortunately, there’s not much you can do about a moldy carpet. Your best bet is usually to get rid of it. Even carpet that has become soaked through (but not yet become moldy) should simply be removed, as it takes longer to dry out than the time it takes for mold to form.

Tiles and Grout: Scrub away mold with a household cleaner like bleach for the best results.


3: Sewage

Does the odour in your basement smell more like sewage than mold? Your nose can tell. A sewage smell is probably due to a plumbing back up. It could be a clog that’s keeping sewage in your pipes, a crack in your sewer line, or just a seal that’s broken that usually keeps odours from coming back into your home.

One of the big differences in service we provide at Sewer Squad is a camera inspection of your plumbing. When we snake a drain, we inspect the plumbing with a camera to find the source of the issue.

We view the results on an iPad and you can take a look as well, without having to be in the same room as the foul odours coming out of your pipes. Camera inspection gives us better insights into the nature of the problem so that we can clean out clogs thoroughly or replace pipes as needed.

If you’re replacing your plumbing due to stubborn smells or corrosion, it may also be a good opportunity to install new fixtures in the kitchen or the bathroom. In addition to emergency drain repair and cleaning, you can also ask us about experts and installations for conventional household plumbing as part of a home renovation.


4: Wet Drywall or Fiberglass

Wet drywall has what’s best described as a musty smell, while fibreglass produces a sulphurous smell like rotting eggs. Building materials in your wall can get wet due to leaky plumbing or a ceiling leak. In the basement, plumbing is a likely cause of wet drywall and you need to fix or replace the pipes first.

If a pipe bursts or leaks in your home, your basement ceiling can get soaked, and that can become a problem. First of all, there are structural concerns, as the loss of structural integrity and water weight can cause drywall to come crashing down.

If drywall is bubbling or drooping, there may be water actively pooling. Drain it by setting up a bucket and using a nail to puncture the drywall. Then you should find the source and fix it, whether it’s rainfall or a plumbing leak.

Mold can bloom within a matter of days and quickly spread, causing that foul basement smell. Replacing drywall is easy enough, but you have to locate the source of the water damage. The drain experts at Sewer Squad can help you inspect your plumbing and fix any problems. You can also check out our latest promotion on emergency repairs and fix any leaks that have been causing mold growth.


5: Iron Ochre

Is there a rust-coloured ooze around your water heater or pipes? Iron ochre, also known as iron bacteria, lives by oxidizing the minerals you find dissolved in water, including iron. It turns into a rust-coloured gelatinous slime that can also give off a foul odour. Because of the way it oxidizes, it can also be extremely harmful to your pipes, worsening leaks and cracks.

Iron ochre smells unpleasant, to say the least. The smell might resemble sewage, though it can also be described as swampy or oily. It will also leave nasty, stubborn stains on everything it touches, especially concrete. Concrete is a porous material that soaks up moisture, meaning iron ochre stains will be especially difficult to remove.

When iron ochre grows inside pipes, it will cause clogs and quickly corrode pipes. It can form inside pipes, at the end of faucets, and inside water tanks or pumps. If you’re worried about iron ochre corroding your plumbing, have your drains cleaned by the drain experts at Sewer Squad.


Emergency Plumbing in Toronto

These are ongoing basement problems that can lead to foul odours, but not every source of bad odours happens slowly. A sudden leak or flood can cause extensive damage and lasting effects, including foul odours and negative health effects.

Don’t let emergency plumbing issues linger when they happen. You can reach Sewer Squad for emergency plumbing in Toronto 24 hours a day, 7 days a week. Plumbing disasters never happen at a convenient time. Give us a call when you need a drain expert to come to your home fast.

You can also call us for any emergency drain problem. Besides bad odours in the basement, we’re often called about municipal water main services such as a water main break. Don’t hesitate to give us a call.


Cleaning Basement Odours

Once you’ve identified and fixed the source of basement odours, it’s time for some cleanup to make sure the smell isn’t lingering. You will need to remove any moldy or mildew objects, wash (or toss) any fabrics that have picked up the smell, and seal away papers in airtight containers.

Cleaning books or papers is difficult – if they’re documents you need to keep, lock them away where the smell won’t come out and permeate the basement again. You can save yourself a second call to the plumber by taking care to seal away any possessions affected by bad odours.

Next, you should deal with any furniture you plan to keep by airing it out. Low humidity and hot, dry sun can help. Finally, clean the basement using borax, a mineral-based fungus-killer that’s great for basements. All you need to do is use 1 cup of borax in a gallon of water and scrub the walls and floors affected by the odour.

Don’t forget to call a plumber and fix the problem before you clean up. Otherwise, the smell will be back with a vengeance.

24/7 Emergency Plumbing Services in the GTA

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