Water damage may spread to other areas not otherwise affected by primary water discharge, causing secondary damage thereby rapidly increasing the scope of insurance claims while increasing claim costs.
Transfer stains occur due to wood and metal furniture, especially antique, staining carpeting.
Discoloration of furniture.
Paper goods start to swell, warp, and split.

Furniture delaminates or starts to swell and/or warp, legs begin to split.
Wet Drywall begins to soak up the water
Finish Building Materials begin to swell, warp and split.
Musty Odor becomes apparent from the standing water.
Tarnishing of uncoated metal surfaces.
Normal household odors become more apparent.
A Clean Water intrusions starts to become a Grey Water situation

Water damage becomes a Grey Water intrusion
Fungi appear, along with a stronger musty odor.
Internal components in pianos and organs swell and warp due to the effects of water or elevated Relative Humidity (RH) (>60% RH).
Wet Drywall (Sheetrock, gypcrete) and other porous building materials begin to swell and disintegrate.
Uncoated metal surfaces begin to rust.
Door and window casings swell and warp or split.
Wood decking, joists, studs begin to swell, warp and split.
Electronic components may malfunction.
Health Hazards associated with Indoor Air Quality (IAQ) becomes an issue
Occupants with health issues or compromised immune systems begin to experience distress.

A Grey Water intrusion turns into a Black Water situation
Mold spores associated with the building materials prolonged exposure to water damage starts to erode natural fibers, paper coverings on wet drywall, paneling, and other building materials
Building materials comprised of wood components warp and split, while chemicals within wood dissolve discolor or destroy finishes.
Claim costs on Water Damage Insurance Claims escalate dramatically; demolishing and replacing contaminated building materials becomes necessary.
Serious occupant health hazards abound; liability increases on insurance claims
The Indoor Air Quality (IAQ) turns into a serious health hazard and proper Personal Protection Equipment (PPE) is required to enter the area effected by water damage
Serious consideration should be made to contacting an Industrial Hygienist (IH) to perform mold testing and formulate a mold remediation protocol