Backing Separation

Description
The top of the carpet may start coming lose from the lower layer under the influence of heavy traffic or decomposition of the glue joining the two backings. The backing of a carpet comes in two parts- 'primary backing' is the one that is attached to the face yarns while the 'secondary backing' is glued to the floor. These two layers are attached together using latex glue. This is also known as delamination.

Cause
This is caused when latex deteriorates under the influence of age and strong physical forces also overwetting. Though a more expensive (and hopefully a better type of) latex may not break down as rapidly as inferior quality latex, no variety is immune to eventual decay.

Treatment
The primary and the secondary backings can be glued back together but it might be a costly and labor intensive procedure. It may actually be cheaper to invest in a superior quality carpet (backing) or to replace it, if damaged in a flood replacment via your insurance company is best and if damage  is caused by the cleaning company the their third party insurance should pay out.