Many homes have a damp basement smell that is oftentimes strong and overwhelming. As soon as the house-basement door is opened the musty odor permeates throughout the house. Some homeowners avoid using their basements for storage for fear that the mildew smell or musty odor will imbed itself in the items stored. Basements have a mildewy, moldy or musty odor for one reason – water. Water is the enemy of a house for many reasons including mildew, mold, wood rot and mildew smells or musty odors. Many basements have no indications of a leak, which leaves the homeowner to wonder where the damp odor is coming from. Those who live near a beach, shoreline, river or stream tend to struggle with damp smells more than those who live in areas that are dry.

Getting rid of the damp odor in the house-basement is a priority for many. In order to make the house-basement a part of the living space or to use it as storage for clothing, linens, books or other items that aren’t used often the problem needs to be addressed. There are quite a few steps homeowners can take to get rid of the mildew odor and freshen up the air.

Inspection Begins Outside


Start outside the home by inspecting the gutters. Clean the gutters to remove dead leaves, twigs, nests and other debris that maybe causing a clog. If the gutters or clogged, the water runs off the roof, into the gutters and splashes over the sides. The water can soak the fascia board and get in under the shingles, run down inside the walls of the house and end up in the house-basement.


Examine the downspouts and clear clogged downspouts that can leave puddles of water near the foundation of the home. As the soil soaks in the water, a process called hydrostatic pressure pushes the tiny water droplets through the masonry structure into your basement. Add extensions to the ends of the downspouts to carry the water further away from the house than the existing distance.

Chimney Flashing

Climb up on the roof and inspect the flashing around the chimney for cracks, lifting, gaps and missing pieces. If there is damage to the flashing, repair the flashing with roofing cement. Damaged flashing allow water to enter the space next to the chimney and can flow all of the way down to the house-basement.


Check the windows for gaps or cracks around the window frame. If there is damage, remove the existing caulk and recaulk the windows with an exterior-grade latex caulk. Just as with the chimney flashing, water can leak in around the window frame and seep all of the way down to the house-basement leaving a perfect environment for mold and mildew growth that will emit a musty odor in the house-basement.


Inspect the roof for lifted shingles, cracked tiles or other damage. If possible repair the section of damaged roofing or consider having a second roof put on or tear the old roof off and install a new one.

Inside the House


Check all plumbing pipes running through the house-basement for condensation or leaks. If the pipes are sweating wrap the pipes with insulation to minimize the water. If pipes are leaking repair the leaks.


Check the washing machine, dishwasher, refrigerator, hot water heater, radiators and baseboard for signs of leaks at connections and along hoses and pipes.

Sinks and Toilets

Check the pipes under the sink along with the sprayer hose to make sure water is not leaking into the house-basement.

Getting Rid of the Damp Basement Smell

Set up a dehumidifier to pull excess moisture out of the air. If the basement is large, consider getting two dehumidifiers. Remember to empty the dehumidifier daily if it doesn’t have a discharge hose.

Fill plastic containers or old metal cans with charcoal briquettes and set them around the basement. Charcoal absorbs musty odors and helps to reduce dampness. Every two to four weeks depending on how damp the basement is, take the charcoal outside on a dry, sunny day and lay them out to dry or replace the charcoal with new charcoal.

If you are storing items in the basement, store them in plastic containers rather than cardboard boxes. Throw away old papers, carpets, rugs and newspapers. Paper and textiles absorb the musty odors and worsen a mildew smell in the basement.

Fill old cans, a bucket or shallow pan with cat litter. Cat litter is made to draw in dampness and deodorize. Dump the old cat litter and fill the containers with new cat litter every two to four weeks.

Wash linens, clothing and other textiles that you have stored in the basement. The fabric fibers retains a damp, musty odor and may make you basement smell.

Fill cans or leave open boxes of baking soda around the basement to absorb the mildew smell. You can also sprinkle a layer of baking soda over the floors and let it sit for a few days. Sweep or vacuum the baking soda and dispose of it.

Leave dampness removal products around the basement such as Damp Ridto help reduce the dampness in the basement and the smell.

Mix equal amounts of chlorine bleach and water in a spray bottle. Spray masonry walls and floors and scrub them with a scrub brush.

Sprinkle bleaching powder also referred to as chlorinated lime over masonry floors. Let the powder remain on the floor for 24 hours. Sweep the floors to remove the powder. Wear safety goggles and a dust mask when sweeping bleaching powder.

Set up an ionizer in the basement. Ionizers release ions into damp air that kill the odor causing particles and atoms.

On warm or hot dry days, open the windows in the basement and throughout the house. Place fans in the basement pointed toward the open windows to move damp air out and allow dry air to enter.

Paint masonry walls and floors with waterproofing paint to stop water from leaking through the foundation walls into the basement where it causes the damp, musty odor.