A common cause of water damage occurs when potted plants are placed directly on a rug. The plant is watered regularly, the pot leaks, and the rug under the pot stays permanently damp. Within two or three weeks the foundation of the rug can become so weak that chunks can be torn from the affected area by hand. If you use planters near a rug, try to place them on a slim legged stool, or a caster-based support that lets you see under the pot and allows for ventilation. After watering the plant check to be sure the rug under it is completely dry.
Another form of water damage can affect rugs used in a basement or other area below grade level. If the basement floods the potential for damage is obvious. The rug must be removed quickly, properly cleaned, and allowed to dry completely. A more insidious form of damage can be caused by using a rug over a damp floor (as is often the case if the floor is cement). Even though the floor is not noticeably wet to the touch, there can be enough moisture to allow microorganisms to flourish in the material of the warp and weft and to degrade the strength of the rug’s foundation.
A rug damaged in this way will often feel peculiarly stiff when manipulated. The rug will sometimes be so stiff it will be difficult to roll, and if you listen carefully to the back of the carpet when it is creased or folded, you can often hear the cracks and popping noises made by breaking warp and weft fibers.