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Mold/Mildew in one room in house...


Hi - I have a problem with one room in our house. A little background will help explain the problem. The house is an earth berm home (ie., basically dug into the earth - on a concrete slab) and we had it enlarged several years ago. It appears that the drain tile was improperly installed and the grade of the soil around the new part of the house is wrong so that we have had rainwater literally flood the new part of the house 3 or 4 times. One room in particular has gotten a lot of water in it and that's the room with the mildew problem. We are in the process of getting the draintile and soil grade corrected, but this room seems to have a mildew problem. the floor is bare concrete and has been for a year til we get the water problem fixed, but it is quite damp and I have found mildew on several things in it recently, and there was a strong mildew smell.  After a lot of research, I bought a gallon jug of Microban RTU and liberally sprayed the concrete floor. it seems to have helped quite a bit, as I don't smell mildew anymore but more a musty, damp concrete sort of smell.  Long and short of this question - did I (or CAN I) kill mildew spores in the concrete and how do I get rid of that damp concrete smell? Would sealing the concrete in that room be the thing do do? And which type of sealant would be the best - I was looking at sodium silicate ones but I would very much welcome ANY input you have on this problem!

thank you for your time in reading this very long question/problem and I appreciate any help you can offer!


Hi Kim, thanks for your question. I actually built an earth berm, passive solar house in Northborough Massachusetts back in 1982. It is there today and uses very little energy to keep warm in the winter and cool in the summer. I hope your home performs well in this regard too.
The fact is that if there are these three things, moisture, air and a food source, then mold can grow. When mold is alive and growing, it "off gasses" the "musty" smell. So, you do have active mold growing somewhere in that room. It absolutely needs to be determined exactly (where the mold is growing) and (why) otherwise you will never "kill" it or resolve the musty smell. I cannot help you determine that being 25 miles west of Boston unless I come there and see and perform tests in the room myself. I have never been to Nebraska, and I'd love to come but you may not wish to pay my expenses. So, you need to find a "mold remediation" expert close by where you live to help you. You can start to find one by contacting your local Board of Health department in the town/city where you live. They may be able to help you.
You can also buy mold test kits at Lowes, Home Depot and many hardware stores and test for mold yourself.
Without question you need to find the source of moisture that is keeping the floor or walls wet enough for mold spores to grow. That moisture source needs to stop if it is possible to do so. If not you will need a dehumidifier in that room that will dry out the air constantly.
You can also get a lot more information from the following two web sites; and They have all kinds of information and resources to help people with mold.
Good luck! Daniel


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Daniel Cetrone


I am probably able to help you understand the mold problem you are having, why it is happening and what to do about it! Most mold problems small, thus easy and simple to remediate. Large mold problems are a different case! They can cause an entire home to be unhabitable!


I am a residentail contractor with 29 years or experience remodeling, repairing and building homes. Throughout many of those I handled insurance damage restoration and remediation projects.

Fitchburg State College, Secondary Education Major, Industrial Ars specialty 1975 Water Damage Restoration certification from (IICRC) Institute of Inspection, Cleaning and Restoration Certification 2000

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