An A319 returned to the departure airport when a failed vent skin valve compromised the flight crew's ability to pressurize the aircraft.

Narrative

We took off from Runway 25R and at about 2000 FT we got an ECAM alert showing a vent skin valve fault. I took over both the flying and the ATC communication to enable the Captain to contact both Dispatch and Maintenance Control. We followed the irregular procedure in the flight manual. The Captain put the extract fans in override. I was already climbing through 11000 FT. I requested a descent back to 10000 FT and requested vectors while we sorted out the problem. We depressurized. I requested an altitude of 9000 FT so we were not at the cabin altitude limit. While I was receiving vectors; the Captain was trying to sort out the problem with Maintenance Control. While listening to the Captain's conversation with Maintenance Control; there seemed to be confusion as to what was the actual status of the aircraft. After discussing it; my Captain and I decided to return to LAS to sort out the problem and obtain adequate fuel. After landing I assessed my own personal ability to continue; and decided it would be best to put myself on fatigue for the safety of the operation. Since I am facing furlough; surplus; or both; my external distractors contribute to the tolerance levels I can now handle of stress. The following day I completed the remainder of the ID without further incident.