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Mold/Mold Behind Drywall


Hi Daniel,

We live in a condo in a 45 year old building.  When we purchased it we noticed stains on one outside wall.  The owner said that water was coming through the bricks and rusting the drywall nails that caused the stains.  Supposedly they pointed the bricks, we painted the walls and haven't had a problem since.

Now I'm beginning to see similar stains on another outside wall, but the walls seem to be dry.  

How can I tell if those bricks also need to be pointed?

How can I tell if there is mold behind the walls without taking of the drywall?

If I do have mold, what is the best way to remediate the problem?

Thank you for your help.

Hi Steven, what you are asking of me is something that you probably should be asking the owner to do. I presume that you are a tenant renting from the owner. Have you brought this new situation to his/her attention? If you are seeing stains on an inside wall it is likely to be caused from some sort of mold situation but without proper testing it is simply a guess. You can buy a mold test kit at Home Depot, Lowe's or many hardware stores to test it. Brick walls are not moisture proof. Moisture can penetrate them and pass through to interior walls if the installers did not put a proper moisture barrier inside the wall. That moisture can cause anything that is made of metal to corrode (rust). The stain you see on the wall can be a rust stain. Or is can be a mold stain. Again you would need to test it to know for sure. If moisture is getting inside the wall there are a number of remedies that professional in the mold remediation business can advise you on. Here are two web sites that may help you. and
You can send some pictures to me if you want my further opinion on you situation.
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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