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Smells in the Basement Answered

I have multiple smell problems in my basement.  A bit of information to assist:

The floor is a concrete slab
The outer walls are made of cinder block
About 80 percent of the outer walls are under ground (on the outside of the house)
There are two rooms in the basement, a laundry room and a finished room (currently used as a bedroom)
It is bare cinder block wall on the exterior wall in my laundry room
It is drywall over wood frame wall against the cinder block (with fiberglass insulation) in the finished room
The laundry room has some bare concrete and some vinyl stick on tiles as a floor
The finished room has concrete slab (unpainted and untreated)  covered with carpet padding and then carpet
The carpet in the finished room is about four years old
I have had the entire basement tested for mold. mildew, etc. with the results showing none.
I am not sure when the house was built.
Our house is near Annapolis, Maryland

The two smell issues are as follows:

The laundry room always has a pretty strong musty smell.  In the winter when it is cold, the smell is not as strong.  As the weather warms up the smell gets stronger and stronger.  I have read that the warm weather draws moisture into the basement threw the walls creating the smell and that a dehumidifier will eliminate.  Dehumidifier removes a lot of water daily and may help a bit with the smell but does not get rid of it.

The finished room has an odor problem that does not seem to be in the entire room but is certainly present in one corner of the room where the two exterior walls meet.  The smell is not really strong on the walls but pretty strong in a 4X4 section of the floor in the corner.  My wife smells it all of the time, I can smell it when I put my nose top the carpet.  My wife ha a nightstand near that corner and can smell the odor in cloths that she keeps in the nightstand.  This section is in the right corner of the room.  In the left corner of the room, we have a 4X8 walk-in closet.  She smell the odors from both rooms in the walk-in closet and also smells it in her clothes that are in there.

Any help with either of these issues would be greatly appreciated.


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5 years ago

Musty smell signifies the existence of mold and should be dealt with immediately. Maybe this is spreading to the nearby room too. Mold can cause health problems. My basement had leak problems which lead to the development of type-1 mould. I got rid of this upcoming health hazard with the help of experts in mold removal at Oakville ( http://www.healthyenvironmental.ca/services/mould-removal/ ) .


6 years ago

I had moisture problems in a basement before and in the end I gave up and moved into a different place as the owner was not that interested in fixing.

First thing to test are the the drain pipes for rain water and those inside, especially in the laundry.

Cracked pipes are always true fun :(

For those inside you can use ammonia, simply will all drains with a good amount and close the openings tighly with a plug and tape where you have overflows.

Do that in the evening or best when you leave the house for a day or two.

The ammonia will the way thorugh cracks and holes and after a good venting you should be able the smell coming back in you smelly spots a few days later - not strong though.

Wood inside the walls can also cause smells when it starts to rot, and it does not always rot due to moisture.

Costly but well worth it is actually sealing the outside walls from the outside and to add good, waterproof insulation along with adequte drainage.

There are companies that offer moisture checks of walls, ceilings and floors, it is a good investment to use them as these guys can locate "wet" spots using infrared and sensitive sensors to pick things up we simply can't see or feel.

As a short term solution I suggest the use of an Ozone generator.

Small device are quite cheap but don't go dirt cheap or for something with extrem Ozone output above 2000ppm.

In the ideal case the generator is working without you noticing any ozone smell at all - if you do the intensity is too high.

Getting higher ozone levels is not easy, keeping high levels low is as easy as using a timer on a more powerful device.

Ozone helps in your case in two ways:

a) it removes ANY smells from the air, including cigarette, cooking smells and sweaty feet ;)

b) it kills bakteria and fungus preventing harmful stuff to grow out of control

Keep in mind that an ozone genrator might remove the smells you don't like but it won't cure the problem causing it.

And: Merry X-mas!


Reply 6 years ago

Thanks for the input. I should have added that I tried the ozone generator and my wife could smell it at any level. Additionally, she read up on them and the end result was that they are unhealthy to use. We have no pipe or drain leaks (we have already tested those), the smell is coming through the wall (in the laundry room) and the floor (in the bedroom).

We will look for a company that does moisture checks. How expensive is that?

Thanks and happy holidays


Reply 6 years ago

It depends...
I had 5 rooms checked (europe) for abour 200$.
But in return I got heat images of all walls and floors, fungus readings and a list of companies dealing with the resolution of the problems.

Did not go that far though as the owner did not agree on the costs of fixing.