Water from outside the structure is contaminated and should be handled be professionals such as PuroClean. Even if the water was not from outside if it is there for an extended time then many materials will need to be removed because of the increased contamination from long-standing water. Drywall will soften and may fall, especially from ceilings. Carpet, pad and other floor coverings may need to be removed. Every situation is different! For the best, specific advice, please call your local PuroClean as soon as the damage is discovered.