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Black Mold

By Tim Carter
©1993-2008 Tim Carter
Summary: Black mold and other types of mold have been around us for literally millions of years, but in the past few years they have really gotten everyone's attention. Because many people think the mold they see is toxic mold, they start to wonder what is the best way to tackle mold removal. Mold remediation can be a do-it-yourself job if the amount of mold is not too large. 

DEAR TIM: We accepted a contract to sell our home. After the home inspector discovered some mold, a mold expert was brought in. The two areas of mold, each one measuring about 3 foot by 3 foot, were caused by a burst water pipe that was immediately fixed and the water dried up within 48 hours. Do I have to have the mold professionally cleaned? What about the chronic mold in my bathroom? Barbara S., Lancaster, PA

DEAR BARBARA: To a large degree, I think this mold hysteria has gotten a little bit out of hand. Don't get me wrong, there are molds that are highly toxic and other common molds that can produce life-threatening allergic reactions in highly sensitive people. But everyone needs to understand that mold is a part of the food chain and we actually need it. Mold is just about everywhere outside your home and in many foods we eat. It is just not a good idea to have mold growing on things inside your home.

Black mold such as this can blossom in days under the right conditions. PHOTO BY: Tim Carter
There are over 30,000 known types of molds so you can see that even professional micro-biologists could spend a lifetime and not be an expert about each one. But the rest of us who do not actively study mold on a professional level need to know that mold growth, for the most part, can be easily stopped in a home. The secret is to simply keep surfaces inside your home dry.

Mold spores are already in everyone's home unless you happen to live in a house built like the sterile rooms at the Centers for Disease Control and Prevention where scientists wear special moonsuits. Mold spores are invisible to our eyes as they often are only 3 microns across. The smallest object the average person can see with the naked eye is often 50 microns or larger in size. The spores are actual seeds that sprout and grow into microscopic plants when they come into contact with water. They are everywhere in the average home just waiting for water.

The mold spores in your home must be in contact with an organic substance like food, dust, paper, cardboard, dirt, leather, etc. in order to grow. Surfaces such as ceramic tile and even stainless steel can have mold on them, but the mold is growing in and on a thin invisible layer of dirt, grease, oils, body skin cells, etc. As soon as the spores come into contact with water, the outer surface of the spore dissolves and starts to soften the organic material. Small roots grow out of the spore much like a regular plant into the softened organic food source.

Some molds need very little moisture to flourish while other molds need lots of water to quench their thirst. But when you consider how small the mold spores are, you can see it doesn't take much water to get them to grow. In fact, the water needed to start and support the mold's life cycle can be an invisible fog of tiny water droplets that are also invisible to your eyes.

This is one reason people have so much trouble controlling mold growth in bathrooms such as yours. When you take a steamy shower you see the mirror fog up. This same fog covers the ceiling and walls as well and is the water needed to fuel the growth of the pesky mold. This is why bathrooms must have powerful fans that duct the humid air to the exterior of your home, not up into your attic.

After you have bathed, tub and shower walls and shower doors should be squeegeed down to direct as much liquid water as possible to the drain. Bathroom shower curtains need to be shaken to remove as much water as possible. Leave your shower door, shower curtain and bathroom door open when you leave the room. You want all surfaces to dry out as rapidly as possible.

The mold the inspector found does not have to be professionally cleaned. Since each area is less than 10 square feet, it falls within the guidelines of do-it-yourself cleanup as stated by the Environmental Protection Agency. When surface areas get larger than 10 square feet, it might be necessary to call in a professional that works with special protective clothing and breathing apparatus and is able to minimize or eliminate the spread of mold spores throughout the rest of the house.

It is very wise to wear an N-95 respirator when cleaning mold. The cleaning process can liberate additional mold spores into the air that can cause mold to spread and more importantly, create health risks to those people who are allergic to that particular mold.

It is a good idea to lightly mist the area to be cleaned with a biocide solution such as regular chlorine bleach and water before you start to clean it. Wear rubber gloves and goggles that do not have ventilation holes. You want to avoid getting mold on your skin and in your eyes.

If possible, try to place a large fan in a window in the room you are cleaning to exhaust mold spores outdoors. Imagine the air being filled with smoke. The air will be filled with mold spores as you disturb the surface you are cleaning, so try to exhaust as many spores as possible outdoors.

Be sure to rinse well all cleaning tools, rags, etc. immediately after cleaning. Wash all clothes immediately so they do not grow mold in the clothes basket or hamper. Dry all cleaned surfaces with rags, paper towels or a fan. Remember, the key to stopping mold growth in its tracks is to prevent water from getting on any interior surfaces of your home.

 






Comments

Ricky Cole
12 Dec 2007, 16:49
Dear Tim,

We live in a basement apartment in Orem, Utah. I noticed that every now and then there will be a nasty moldy smell that will fill our apartment. I later noticed that it only smelled bad when the landlord upstairs would use their clothes dryer. I thought that maybe the dryer vent came attatched and was blowing through the walls and sockets. Immedietely the thought of mold came into mind. After a few months of worrying about it, I decided to pull the dishwasher in the kitchen away from the wall to locate the source of warm moist and stinky air. I was disgusted to what i found. Someone has cut away a section of drywall about 1'x2' and i could see a water pipe that serves an outside hose bibb that was leaking water (quite a bit) There is mold EVERYWHERE, and the dryer vent makes it very warm. It is so disgusting! I wanted to find some advice before talking to the landlord about it. Do you any idea what kinds of mold could grow in these conditions (Dark WET and Warm environments) Do you think i should have an inspector come in to test it? I don't want to live here if its going to danger my new born baby.

Thanks so much for your help.
AsktheBuilder
15 Dec 2007, 08:23
Ricky,
This is a VERY serious situation. You need to take immediate action. Call the landlord. Move to a friend or relative's house. Contact the local Public Health office on Monday.
Shawn O'D
24 Dec 2007, 13:54
Dear Tim,
I live in a custom built Santa Fe style home in Apache Junction Arizona.. Ever since the house was built some of the windows have had leaks below them where water will puddle up.. I know its coming from the windows. When I showed the contractor he said it was the windowsill and that the water was draining in the house insted of out.... He has since re sculped two of the worst ones and they still leak... His other solution was to put calking along the bottom that didn't help either.. Now I see black mold at the floor of 5 of my windows... #1 I'm wondering how to fix it. Do I need to reinstal all my windows? #2 Is the contractor still responsable for this? My house is 6 years old.. I also know that all my windows were installed without any window flashing by the contractor.. I would rather not use the same contractor for fear of the same results.. I also have a sliding glass door with the same problem.Please help, what can I do to save my house and my health.. Good thing it doesn't rain allot in Arizona..
Thanks,
Shawn O'D
Anita
07 Jan 2008, 07:29
Hi Tim,
We added onto our home about 12 years ago. We installed many new windows mostly Pella, from a major chain discount store. Every year we have had condensation on the windows. We now have areas of black mold (I am sure that's what it is) staining the window between and adjacent to the pane area and the wood frame itself. Pella told me I had broken the seal by using a razor blade to scrape away varnish after I varnished the windows years ago.
The wood sliding glass door also has this mold between the two sections that slide by each other in the winter also. I have asthma and notice the increase in respiratory problems. I have tried to clean the areas up in the summer with bleach and then revarnishing and the condensation returns every year and the black staining returns. HELP!!!! what can we do short of replacing all these windows again? My husband is very frustrated and so am I. Anita
AsktheBuilder
07 Jan 2008, 07:38
Anita,
It is a water issue. Read all of the columns in my Condensation category and all of the columns in my Mold section. Follow my advice to the letter.
Alex
08 Jan 2008, 16:43
I had a water leak come through my wall and it was covered by a huge mirror. I found black mold behind it. Got rid of the mirror and completely saturated the wall with Chlorox, no water just straight chlorox. The mold disintegrated. It looks like it never happened. I had the leak fixed. My question is, will that be enough or do I have to replace the wall? The mold only covered a couple of feet across. Thank you.
AsktheBuilder
08 Jan 2008, 17:11
Alex,
Beats me....... Is the wall sound? It is impossible for me to comment if I can't tell its condition.
Sorry!
Dawn D.
17 Jan 2008, 12:36
Alex,
My husband and I live in a manufactured home and it was built in 2003 and we moved in in August 2003. After 4 years of living in the house, water is now running in from our bathroom into our kitchen. We have black mold on 2 of our walls and mold in the flooring of our bathroom. It appears that the piping wasn't installed properly when the house was put on the land. There is a bag and foam around the pipe from the ground to the house that has been cut and tape put over it and the washer and nut are glued on. Can my house be saved?
AsktheBuilder
18 Jan 2008, 06:44
Dawn,
I am not Alex. Have no clue where he is. You need to call a fantastic remodeling contractor to tell you what needs to be done to fix your problems.
Chris Burton
22 Jan 2008, 15:33
Hi Tim,

Black mold has been uncovered behind the walls in my apartment when a leak developed.

I've read a lot of articles saying that chlorine bleach does *not* completely kill the mold because of it's ionic factor.

Do you know of a product that will kill the mold forever?

Thank you for your time.
Sincerely,
Chris Burton

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