How to remove toxic mold and smell in drain pipes

Anywhere there is moisture that sits for a prolonged time period and is a food source, you are most likely going to find mold.

That is why a favorite hiding and breeding place for molds (fungi) is in and on the drains (pipe sweating) of your property.

Your drains serve as the delivery mechanism for all the dirty water and food waste that your property produces and delivers it to the city sewer pipes.

Over time, these wastes such as human hair, dead skin, and old food deposits start to build up in places like the the P-trap, which is the S-shaped pipe located underneath the sink and other areas.

The odor may be coming from the drain trap, which is designed to hold water and prevent sewer gases from entering your home through the pipe. If the trap has a clog from hair and other debris, it can’t do its job properly.

One of the best ways to get rid of an odor in a bathroom drain is to remove the clog.

The build-up is the perfect food for various molds and bacteria that will start to grow on the inside of the pipes if you do not clean and maintain them properly. This is a problem that is more common in older homes, but can happen anywhere.

As these microorganisms start to thrive, they reproduce more offspring as millions die to then become food for the new generation of microbes. Before you know it, your drains will be covered in a thick, pathogenic and toxic bio-slime that will create a foul smell.

Worse yet, this thick mold sludge may also lead to clogged pipes and extensive water damage. That is the last thing you want to happen!

Not only do these molds and bacteria create this unpleasant odor in your home, they can also cause health problems for you and your family.

According to the CDC and EPA, some molds can cause respiratory problems including allergies and asthma. Other molds may actually be more toxic or carcinogenic.

How do you clean the drain pipes?

Here are 5 quick steps to removing the smell from your drains:

Step 1: Expose the drain or remove the drain trap

You will need to remove the drain cover if this is for a shower or sink drain so you can clean it out properly.

If the smell is also coming from the trap, you may have to remove that as well if possible.  The trap is an elbow-shaped pipe that’s located in your sink or tub drain underneath the sink.

Some traps have a cap that can be unscrewed, while others have to be removed using a wrench or pliers. Water will drain out immediately, so have a small bucket or bowl and rags handy.

With a shower or tub, it may not be possible to remove the trap unless you can gain access from underneath via a basement or crawl space with adequate room to perform the work.

Step 2. Remove all hair and debris

To remove hair from any of these areas, first use your plunger to clear any debris out of the drain pipe. Then use a pair of pliers to grab hold of any strands that might be caught in the drain opening.

Even better than pliers, purchase a plastic snake drain tool that can go deeper and is more effective. They feature sharp edges to easily grab strands of hair and gunk stuck inside your plumbing.

Step 3. Clean the drain trap

Make sure you remove al the hair and gunk Get half a cup some baking soda and slowly pour it down the offending drain and let it sit overnight. This will start to kill the mold and dry up the slime.

Step 4: The next day, get 2 cups of white cleaning vinegar or hydrogen peroxide and pour it down the same drain. It should start to foam.

This will also kill the mold and start to loosen the mold colony’s hold on the inside of the pipes.

Step 5: Next, get about 5-6 cups of very hot water (not boiling) and then pour it down the drain to wash away the dead mold, baking soda, and vinegar or hydrogen peroxide.

You do not want to use boiling water because it can damage your pipes and connections. Especially if they are made of PVC.

Bonus Tip: Flush out your pipes and clean them periodically to prevent bad smells from developing in your drains using the steps listed above. You can also do this once every two weeks or one per month to stop mold from growing and to maintain clean pipes.

If the foul or mold smell does not stop after cleaning

If you have cleaned out your drain and the smell continues, think of the odor as a warning sign that something in wrong with your drains.

If so, you most likely have a mold problem or the sewer gasses are leaking into your home from the drains.

This may also be a sign that your drain is not properly installed and or the lead seal around the drain has failed or become rotten. Sometimes when the lead seal fails, people will attempt a cheap fix by trying to caulk it with silicone which rarely lasts.

In order to locate the problem, all you will need to do is take off the drain cover and perform a visual inspection of the drain pipe and seal. What you are looking for is mold growth and any gaps around the drain pipe and shower pan.

If there is a gap around the pipe, then you most likely have a serious water damage and mold issue hiding within your floors where the pipe is located. If it is located on an upper story of a multi-story property, you most likely now have water damage and mold running down to the bottom floors.

For example, here is an image of a shower drain pipe that is not only installed incorrectly, it also has black mold in and around the pipe.

If you find mold in your drain pipes, and or a defective seal or a gap around the pipe allowing water to leak, your safest bet to get immediate relief is to place a temporary vapor seal over the infected drains because you and your family could be breathing in the toxic off-gasses and mycotoxins from molds (fungi) and bacteria.

Next, you need to determine if it can be cleaned and fixed properly.

If it is just mold, you are in luck and can most likely clean it pretty easily. If you have a defective seal or gap around the pipe, you may now have extensive water damage and mold hiding in your floors and within your walls.

To handle this type of problem properly, you would need to have your property professionally remediated and the plumbing repaired. This can get expensive and there is no quick or cheap fix.

The good news is that your homeowner’s insurance may take care of the problem if it is an active water leak.

I recommend that you inspect your drains often for any signs of clogging, leaks, microbial growth, and foul smells. If any leaks or smells are found, fix or clean them immediately.

Contrary to popular belief, you do not want to pour bleach down your drains.

Bleach is made with highly toxic chlorine that can produce gasses that you are your family breathe in, and it also contaminates our environment and our oceans. People who use bleach in their homes and poisoning themselves, their families and the world, so don’t let that be you!

A quick, safe and easy fungicide you can make that will kill the mold and get rid of the smell is a combination of baking soda, white vinegar or hydrogen peroxide, and hot water.

If you need a mold inspection, mold remediation, or would like a professional consultation, please or text call us at 760-818-6830.

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