What is the purpose of a flood cut?
For clean small water leaks, only the visibly damaged area may need to be removed to prevent further moisture damage. Unfortunately, flood waters or exceptionally large water damages require extra care, which will likely mean a flood cut for the reasons listed below:
After a very large water damage there may be a good chance of mold growth. With flood waters sewage, chemicals and other bacteria can easily be picked up in the flowing waters.
The large amount of water that has likely worked its way up the walls can create a welcoming environment for mold growth. Even though it may not be visible, the moisture in the drywall and other materials create an environment that the mold needs to grow in.
There is insulation behind the walls in many homes, which cannot be properly dried. If left as is, it will no longer provide its designated insulated properties.
If your home has a very large substantial amount of water damage, the best bet is to use a flood cut. This will help you determine how much of the material needs to be removed, as well as will help the area dry out better.