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Eliminating Musty Odors & Other Smells In Basements

A finished basement that has been completely destroyed by flooding, mold, rot, and mildew.  All materials will need to be ripped out.

Warm air moves upwards in a home, exiting through the attic and upper levels of the building.

As it does, it creates a vacuum, which pulls air upwards from the lower levels. This means that up to 50% of the air in your living space comes from the basement. If the space smells musty, the rest of your house can too.

Some of the most common basement problems that our customers ask us to solve are related to damp, musty, or foul odors. Our dealers are proud to say that we've had a practical, effective solution for every one.

Musty odors in basements will quickly become a much larger problem. As the air moves naturally upwards in your home due a building science phenomenon known as the "stack effect", this musty air will enter your upper levels.

Getting Rid Of That "Musty Basement" Smell

There's a lot of advice out there about the best ways to eliminate musty smells in basements. Some of them work, some do not, and some are just plain dangerous!

A short-term solution is a great way to eliminate a small odor problem -- such as cleaning up cat urine on a basement floor.

However, if your basement has odors from mold, sewage, or water intrusion, your best bet is to stop the problem at its source -- permanently!

We have warranted solutions for wet and humid basements that have been used on basements worldwide for over 20 years!

If you'd like a free dry basement estimate, call or e-mail us today! Our estimates come at no obligation and include an on-site professional inspection, consultation, and a copy of our full-color book!

Candles, reed diffusers, and other scented items.

Air fresheners, incense, and other scented products do nothing more than cover up the odors that you smell..

If you want to create a healthier space, you'll also need to permanently eliminate mold, mold spores, and dust mites in your basement.

Sources Of Basement Odors

Musty odors commonly occur on the basement for the following five reasons:

  1. Mold & Mildew: The most common reason for musty odors in basements is the prolonged growth of mold in the space. Mold growth can be in visible spaces as well as hidden in wall cavities, in carpets, and above ceilings.
  2. Wet Building Materials: Wet drywall has a musty smell, while wet fiberglass have a sulfuric, rotten egg smell.
  3. Animal Smells: Animal waste and urine is a common concern in a basement. Additionally, foul smells can occur when rodents or other pests die in the walls or elsewhere in the basement.
  4. Sewage Smells: Sewage smells are usually connected to a plumbing issue in your home. This can be as simple as replacing a wax ring seal or as complicated as a cracked sewer line.
  5. Iron Ochre: Iron ochre is a rusty-colored, gelatinous ooze that appears in some basements. It as a foul smell that's been described as musty, oily, swampy, or like sewage.

Odors & Your Health

Controlling mold and dust mites in your home will provide the added benefit of making your home a healthier, better preserved space. Less mold and fewer dust mites in your home means lower counts of allergenic mold spores and dust mite waste in your air. It will also mean less rot damage, which could lead to expensive and time-consuming repairs and mold remediation in the future.

More about Basement Mold & Your Health

Warning: Mold Removal Is Professional Work!

If you have a mold problem, it's best to use extreme care in removing it from your home. At Basement Systems, we do not recommend removing mold without professional help.

While rare, it is possible for mold (especially "black mold") to be harmful, toxic, and/or carcinogenic to humans. Other molds are allergenic and may cause allergic reactions in some individuals.

Fumes created during cleaning are also a significant concern when dealing with mold -- especially in the case of combining cleaning agents.

Additionally, improper removal of mold can result in further mold issues down the road. It can be common even among professionals to miss a mold source, leading to serious health and home renovation implications later on.

A bucket containing several cleaning agents such as bleach, ammonia, and window cleaner.

When cleaning dirt, efflorescence, mold, and other stains on your basement walls and floors, take care that you're not mixing bleach- and ammonia-based products together.

Mixing bleach and ammonia can result in in the creation of dangerous substances like chlorine gas, nitrogen trichloride, and hydrazine, depending on the mix of bleach and ammonia added.

Short-Term Solutions For Odors

The following solutions are temporary ways to eliminate mold or musty odors in your basement. These are meant as temporary, "quick fix" ways to eliminate odors only.

These solutions should be used in combination with the permanent methods listed later in this article.

Vinegar & Water: Mix one part vinegar with three parts water. Using a stiff broom or brush, scrub the walls, floors, and other materials that have a musty odor thoroughly.

Throw Out Moldy Organic Materials: Throw out any organic materials that show mold damage, such as boxes, books, or chipboard.

Wash Clothes & Wood Furniture: Moldy musty clothing and cloth stored in the basement should be washed thoroughly. Carefully wash off all wood furniture. Any furniture with deep mold growth should be discarded.

Lay Out Dishes Of Vinegar: Vinegar can help to break down the damp, must smell found in basements. Leave several dishes of vinegar in the basement for 2-3 days to combat musty odors.

Leave Out An Open Bag Of Charcoal: Charcoal can absorb odors and dampness in the air. Leave an open bag of charcoal in the basement, changing it every six months.

Sprinkle Chlorinated Lime: Sprinkle chlorinated lime over the floor of your basement until the must odor disappears, then carefully sweep it up. Do not let pets or children come in contact with the chlorinated lime.

Do Ozone Generators Work?

To eliminate stubborn odor problems in a basement, some homeowners will buy or rent an "ozone generator" - a machine that claims to eliminate odors such as cigarette smoke, chemical odors, cat urine, mold odors, and similar odors.

The United States Environmental Protection Agency makes it very clear that they do NOT recommend these devices, and also suggests that they can be dangerous and/or ineffective to use. Ozone is a toxic gas, and whether it's in pure form or mixed with chemicals, it can be hazardous to your health.

Additionally these machines will not filter the air, and they will not remove large particles such as dust, dander, pollen, or mold spores (even dead mold spores are allergenic). It will also not eliminate water vapor or humidity or provide a long-term solution for mold, mildew, or dust mites.

The United States EPA has this to say about the effects of ozone on humans:

"The same chemical properties that allow high concentrations of ozone to react with organic material outside the body give it the ability to react with similar organic material that makes up the body, and potentially cause harmful health consequences. When inhaled, ozone can damage the lungs. Relatively low amounts can cause chest pain, coughing, shortness of breath, and, throat irritation. Ozone may also worsen chronic respiratory diseases such as asthma and compromise the ability of the body to fight respiratory infections."

Read The United States' EPA's Document On Ozone Generators

Fiberglass that is thoroughly soaked with water from a humid environment.

In the summer, a ventilated basement brings in hot, humid summer air. When humid air is cooled, that humidity will be deposited on surfaces in the form of condensation.

During the most humid times, fiberglass insulation can become soaked with moisture, like in the photo above, leading to rot and mold in both the insulation and the floor joist it touches.

Does Basement Ventilation Help?

The importance of basement ventilation is a building science myth that's costing homeowners a fortune in energy bills and home repairs.

Why Basement Ventilation Fails

Throughout the seasons, you're venting your home with three types of air:

Humid Summer Air: When humid summer air cools in a basement, moisture is deposited on all surfaces. This moisture will saturate your building materials, allowing for mold growth and rot.

Wet-Weather Air: When it's rainy, foggy, or damp outside, basement vents bring wet air into your home. Isn't the opposite of what you wanted?

Cold Winter Air: Your basement is the home of many utilities that are meant to be hot -- like water heaters, furnaces, hot water pipes, and heating ducts. If you bring cold winter air into your home, these utilities are cooled, forcing them to work harder than ever to operate normally.

More about The Case Against Basement Ventilation

Sewage Smells In The Basement

Most sewage smells in your basement are a result of these five common sources:

  1. A Dried-Out Water Trap: The water trap located underneath a laundry tub, floor drain, or wash basin has dried out due to lack of use. As it dries out, sewer gas rises up through the drain and enters the room.

    How To Solve It: Dump a pitcherful of water into the drain to restore the trapwater. Follow up by pouring a couple tablespoons of cooking oil into the drain. The oil will coat the water, which will slow down the evaporation process of the trapwater.

  2. A Missing Cleanout Plug Inside the Floor The Drain: If the cleanout plug is missing from a floor drain, there's a direct path for sewer gas to bypass the water trap and enter your home. Sometimes, these plugs are remove to clean sewer lines and are not replaced.

    How To Solve It: Buy a replacement plug at the hardware store and put it in place.

  3. Dried-Out Water In The Toilet Trap: Weeks of disuse can cause the water in the toilet trap to dry out. As it does, sewer gas is free to rise up and into the living space.

    How To Solve It: Simply flush the toilet, and the trap should refill with water.

  4. The Wax Ring Seal Between The Toilet Flange And Toilet Base Is Defective: This wax ring can occasionally leak -- which is sometimes caused by a rocking toilet whose seal is broken. With the seal broken, sewer gas can escape from under the toilet.

    How To Solve It: Remove the toilet and replace the wax ring. If the toilet is rocking, use plastic shims between the stool and the floor. Caulk the joint completely. By leveling the toilet, you ensure that future rocking will not destroy your new wax ring.

  5. Your Sewer Line Has A Leak: Sometimes, a sewer line will break or crack, or a loose connection joint in the ceiling or buried in a wall will fail.

    How To Solve It: Make sure that problems 1-4 aren't your problem. Then use your nose to start investigating the issue, starting with all visible sewage joints. If you can't find a leak in the line, contact a plumber who is qualified to hunt down sewer line leaks.

The Good News: Most sewage smells have simple, easy solutions! If you're not familiar enough with home plumbing to solve this kind of issue yourself, a home improvement contractor can easily help you solve most of these issues.

Long-Term Solutions To Eliminating Basement Odors

The best way to eliminate basement odors to restore the quality of life in your home (as well as the home's resale value!) is to completely eliminate the odors at their source.

With the problem solved, your home will not only smell better, but it will be a healthier place to live. Your home will have fewer allergens, and your basement will be upgraded to be more valuable, usable space.

At Basement Systems, we recommend the following six steps for a permanent solution:

We Provide Long-Term Solutions For Damp, Musty Basements!

Your local Basement Systems dealer has the experience, training, and products you need to upgrade your damp, musty basement and transform it into dry, usable space in your home. Our products are designed to create permanent solutions for your home that create a more attractive and beautiful space for you and your family.

Our International Waterproofing Network includes locally owned and operated dealers throughout Canada and the United States. To schedule a free dry basement estimate, contact us by phone or e-mail today!

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Quality, Innovation, Patents, Awards

Our innovative and forward-thinking approach to designing products has solved wet basement problems that the basement waterproofing and crawl space industry has faced for decades, and our patented sump pump systems are the smartest and most reliable. Plus we listen to our customers and respond accordingly! Basement Systems Inc. has been awarded 24 Patents and 19 Innovation Prizes on waterproofing products we use every day, including a battery back up sump pump system. This approach ensures the best waterproofing systems and solutions available.