A friend is remodeling their bathroom and found some mold that they need to kill and remove. Unlike most mold that people are worried about this mold is white but that does not mean it isn’t dangerous. So, what precautions should they take and how do they go about removing it?
Mold will occur anywhere there is warmth, food and moisture. Because mold spores are constantly on everything including our bodies we have to take precautions to eliminate it when we first see it growing. In a wall void with plumbing pipe the moisture that will allow the mold to grow does not have to come from a leak it can come from condensation just like on a soda can. Warm Air and a Cold pipe or the other way around and moisture will begin to form. There really isn’t much you can do about it except use good materials that will resist the mold. In bathrooms with high humidity you really should use a fiberglass drywall rated for mold hold out. This type of drywall is also suggested in basements. Pressure treated lumber would be nice but unfortunately its not suited for this area. You could apply a closed cell foam insulation but that is not always going to be a final solution.
Precautions When Working Around Mold
FIRST… NEVER USE A VACUUM CLEANER TO CLEAN UP MOLD OR ANY MATERIALS, DUST OR OTHER IN A ROOM THAT HAS AN OPEN WALL WITH MOLD. YOU MUST CLEAN THE ROOM BEFORE RETURNING TO WORK BECAUSE MOLD WILL GET ON EVERYTHING IN THE ROOM EVEN IF YOU CAN NOT SEE IT. USING A VACUUM CLEANER IS JUST LIKE HOOKING A GARDEN HOSE TO YOUR SEWER LINE AS MOLD WILL REMAIN IN IT AND BROADCAST IN ANY FUTURE AREA IT IS USED.
When you find mold you need to take precautions because it is not worth the risk of getting sick. If the materials are damaged you won’t be able to clean them. It is mandatory that you wear safety equipment that will protect you from the mold. A respirator that is rated for mold should be used and you can find tyvec painter’s suits that should be worn along with nitrile gloves and bags over your shoes. This precaution will take 10 minutes of your time and maybe $20 but in the end its worth not getting sick.
Repairing Building Materials Damaged By Mold
Mold can eat through drywall and it will feed on the paper. I have seen a water leak from a roof eat the top side of a piece of drywall used for the ceiling in a utility room and the painted surface looked fine but you could put your finger through it. There is no fixing that you just need to cut back to good drywall and replace what you need to. In addition wood can be damaged in the same way. Mold Rot on wood makes it unstable and if you can’t cut out a piece to repair it you will need to replace the whole thing.
Basically when in doubt replace anything that has come into contact with mold. If the cost is minimal then don’t even question pulling out some drywall or lumber that has been infected because treatment of the mold is not 100% guarantee that you will remove all of it and then it will grow back faster than it did before.
Treating and Removing Mold
For treating mold the best solution is Bleach. You want to use a high grade bleach that is not diluted. The Dollar Store might have gallons for $1 but it is likely diluted quite a bit more than standard bleach.
Any materials that are covered in mold should be wrapped in plastic and sealed before they are removed from the room. You do not want to carry that stuff through your home in an open way. Trash bags and plastic tarp should help you get the materials to a safe location outside for removal.
The materials that you can not remove should then be soaked with bleach for a prescribed time to kill the mold. Unfortunately all mold is different as is the strength of your bleach so I can’t give you the exact time but at minimum you want to keep the surface wet for 30 minutes by continuing to mist the area with a spray bottle or garden sprayer for larger areas. The mold should change color when it dies however that is also not guaranteed. There are research papers online that you can find more exacting times.
Allow the area to dry and then remove the material using a plastering knife. Secondary treatments may be required.
I like to neutralize bleach especially on wood with strong vinegar. White vinegar 5% is available for canning foods and it will bring the material back up to a neutral acid/base level.
Final Note
Mold can be very dangerous and it doesn’t take a lot to make you sick. If you have any doubts about doing this work yourself especially if the area is very large you should hire a professional.
Remember that when working with mold you want to protect the other areas of the house from contamination and that means a drop cloth on the doorway but you will also need fresh air.
When you are done discard the clothing you were using to remove the mold and never use it more than one day or once. You can not put it back on whether its before and after lunch or the next day.