The source or sources of odors can be very difficult and expensive to determine.

Here’s a quick overview:

Musty or Dank – Excess moisture in the home or commercial space can cause mold to form. Keeping humidity levels below 50% can help with this. Also, exposed earth in a crawlspace or basement can also take on a musty odor. Sealing the crawlspace with plastic (“sealing” does not mean throwing a piece of plastic over the dirt – www.cleancrawlspace.com for an example of a sealed crawl space) and sealing or finishing the basement should improve the odors. It may be necessary to do professional mold testing in the living areas.

Smell of Death – We have heard about everything from birds decomposing in dryer vents to mice caught in the wall cavities of brand new homes. However they get in, decomposing animals smell terrible. Unfortunately, short of ripping out the wall, the only remedy is time.

Sewer – Sewer gas lives in your plumbing. Fortunately, we don’t have to smell it thanks to the “P-Trap” on every drain. That’s the U-shaped bend in the pipe leading away from the sink. This pipe normally has a little water in it all the time to prevent the sewer gas from drifting up into the living and work areas. But, if you have an unused sink or other drain, the water in the P-trap can evaporate, and the sewer gas is released. To prevent that foul sewer odor, run water in all sinks and pour a small amount of water into any floor drains once a month or so to keep the water in the trap from completely evaporating. Also check wax seals around toilets. If the seal is damaged, the same sewer odor may occur.

Fishy – This is the one that seems to baffle homeowners most often. Where on Earth could that fishy smell be coming from? Interestingly, it is usually coming from burnt wiring or something plastic touching a light bulb. Older wiring in particular has a fish odor associated with it when it melts or burns. If you smell something fishy, check your outlets, light fixtures and other sources of wiring for overheating or damage.

Rotten Eggs – That sulfurous odor in your home could be coming from a couple of difference sources. Sulfur is added to natural gas, which is naturally odorless, to alert people to a potential gas leak. If you smell rotten eggs in your home, the very first step is to call your gas company and have them confirm or rule out the presence of a gas leak. Breathing natural gas can be fatal as well as explosive. Once you’ve ruled that out, see if you can get closer to determining the location of the odor. If it is coming from a faucet, then it is likely coming from something called an anode in your hot water heater or well. Check with your plumber for details, but it may be necessary to chlorinate the water in the tank or well.

Chemicals – It might be the smell of nail polish remover, or the fumes from a busy street, diesel or moth balls. The usual “bad guys” that are causing the odors are auto additives, paint, other home repair liquids, cleaning chemicals and beauty products. If that doesn’t eliminate the chemical odor, you may wish to consider testing to scientifically identify what chemicals are causing the odors. Chemical testing is lengthy and expensive.

Cigarette (second hand) Smoke – Cigarettes have an unmistakable odor. We can test, with a special wipe/cloth, if second hand cigarette smoke residue is present. This testing is also lengthy and expensive. You may wish to ask the person smoking to stop and end the problem. For apartments/condos/homes that had a previous long term occupant that was a heavy smoker, sometimes the sheet rock will need to be removed or the building treated professionally with ozone. Don’t confuse professional ozone treatment for either cigarette smoke or a fire with a home ozone machine. We do not recommend home ozone machines. There are commercial applications where an inline ozone system added to the HVAC system is appropriate, but not for residential use.