musty smell in house with inaccessible crawl space


I am buying a house. I cannot access the crawl space. The house has been closed up awhile and has a real musty smell. What product do I need and how do I eliminate the odor?

Homes left vacant for some time will many times get “musty” – with or without crawl spaces. So for now, lets focus on the living areas.

To remove the odor in the living spaces, you’ll want to fog with either NNZ or N7C. These products work on odors directly and effectively break them down so the odor is diffused and no longer present. In other words, they don’t “mask” the scent; they break it down so it can’t come back.

The NNZ is odorless; the N7C has a slight “clean” smell so you know when its been applied, where you sprayed it, etc. Both will work and you only have to choose if you want a slight odor or odorless. As for coverage; 1 jug of each will make at least 8 gallons of finished spray which is enough to treat the average home 3-4 times.

Now the best way to treat is when the house is still vacant and empty. This way the spray will have access to all the surface areas (walls, ceilings, floors, etc.) and you’ll be able to treat unimpeded with a clear and direct path to the target areas. This will allow you to treat with little effort and it will allow you to get the treatment done quickly.

If the home is already occupied and filled with furniture; it can still be treated the same way. It will just take a little more effort to make sure the treatment gets under appliances, furniture, etc. so you don’t miss important surfaces.

As for how to apply it; fogging is clearly the most effective method. You can use a MINI FOGGER or our FOGGER RENTAL machine. Either will do a great job and its really a matter of whether you’d like to own a fogger (which can be used for general pest control like fogging for mosquitoes, gnats, etc.) or if you’re okay just renting one for the job at hand.

Lastly, ask any good home inspector about an in accessible crawl space and they’ll all tell you it would be wise to gain access. This might sound difficult to do but in most cases, you only need to break through a small section of foundation wall and many times this section can be inside the home. Having access to such areas is always smart. And when purchasing a home, its even more important to know what’s happening in every part of the structure so you don’t come to find out the hard way there was some kind of major problem previously hidden in this space.

Now once the area is open, you may or may not need to deodorize. As stated above, just having a crawl space does not mean its responsible for an odor found in the living spaces of the structure. But if you do get access and you’re treating the rest of the home, it only makes sense to treat the crawl space too. And with either fogging machine listed in this response, you can usually get the entire area covered with little effort. Basically you should only need to fog from the entry point you create since both machines can propel a fog 25-30 (and more) feet no problem.

Oh, and one other thing, you can definitely mop or wipe down any surfaces with either product. You can even use a standard pump sprayer to do the treating. Its just much easier to apply it as a fog since you’ll get better coverage, use less material and overall, get better results.

Here are direct links to the information and products listed above:



Mini Fogger:

Rental Fogger:

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