A system dressing and method for providing reduced pressure treatment to a tissue site on a wound bed of a patient includes a variable wound dressing having a variable cover (210) that is pliable at ambient pressure and less-pliable when placed under reduced pressure. The variable wound dressing has a first side (218) and a second patient-facing side (220) and in use a treatment space (268) is formed between the second patient- facing side of the variable dressing and the wound bed. One or more ports (250 256) are used to supply reduced pressure within the variable cover and to the wound site. A reduced-pressure subsystem is also included that is operable to supply reduced pressure to the one or more ports.