Mold can be a worrying issue, but it can only grow in areas of high moisture. It is hard to combat mold growth directly, but it is easy to combat excessive moisture. First, identify and fix the source of the moisture. It may be a leaky pipe, bad insulation, or a broken water appliance.
Next, all wet and contaminated materials must be removed from your home. Even if you do not see mold on it, the roots may be lurking just below the surface. The only way to be certain mold will not return is to remove all materials that could possibly be contaminated. Additionally, you should not rebuild until everything is completely dry. It is always best to let the professionals handle the challenge of removing and preventing mold.