First, contain the mold to keep it from spreading to other areas. Use thick plastic to form a barrier around the affected area.
Second, protect yourself in the affected area. Wear a face mask (respirator would be even better), rubber gloves, and old clothes you wouldn’t mind throwing out if they get contaminated.
Third, find out where the moisture is coming from. Mold needs moisture to survive. It could be coming from a hole in your roof or siding, a leaky pipe, flooding or even a blocked air-conditioner drain. Do whatever is necessary to discover the source of the water and fix the problem, since new mold will continue to appear if you don’t get the water source stopped.
Fourth, test your mold. Either hire a mold inspector or use a dyi mold test kit, but find out whether you are dealing with a toxic variation of mold, such as Stachybotrys or Memnoniella. You or your inspector will want to test each area that may have been affected, including adjacent ceilings, walls, floors, and behind drywall. Cut through building materials to take a small sample. Place each sample in a carefully labelled separate ziplock bag.
Remove moldy items. Once you have your tests done, and you are ready to proceed, remove any items from the area by putting them in plastic bags. When you do this, bring the plastic bag to the item, and seal the bag immediately. Don’t carry the item anywhere before sealing it in plastic, because mold spores are just looking for a way to spread, and they can easily move through the air when being transported.
Items you wish to keep: If there are items in the area that you believe are unaffected, first decide if the item is worth taking the chance. If it is washable, use boiling hot water with mold remover poured over it. Then lay it out in full sun for awhile to kill any leftover mold spores, before returning it to your house. If you have any doubt, it would be better to toss the item (in sealed plastic, of course).
Any exposed drywall should be carefully sealed and disposed of. One area that is especially problematic is the attic, if your mold is located in your upper floor’s ceiling. Since most attics are seldom used, mold can grow unseen for some time. A gap in your eaves may be all it takes to allow moisture to get in, which is what the mold needs to grow.
Use products specifically made for mold removal for the final cleanup. Most professionals will tell you that bleach is ineffective, and allows the mold to return.
The removal of toxic black mold is serious business, which is why a mold remediation service can be a preferred way to go, to protect your home and loved ones.