A B747-200 Captain required a Contract De-icing Crew to reapply Type IV fluid because the hold-over time expired after extensive application of Type IV to deice the aircraft.

Narrative

Forecast indicated snow storm at time of departure. Maintenance requested crew to have doors closed and ready for de-icing ready one hour prior to departure. Doors were closed on the hour. Twenty five minutes later; contract Maintenance contacted crew regarding commencing of spraying. Fifty five minutes later; deadheading maintenance personnel indicated both de-ice truck were still trouble getting snow off the aircraft. As we'd already calculated our holding time (1 hour); and based on the commencement of anti-icing; I determined the de-ice crew was improperly de-icing and anti-icing the aircraft. Communications with the Contract Ground Maintenance indicated low pressure Type IV fluid was being used to de-ice the aircraft; with poor results. I determined that improper procedures were being utilized. Upon completion of de-icing; contract Ground Maintenance asked me if I was satisfied. I informed that no; I wasn't and we couldn't depart as we'd exceeded our holdover time and hadn't been properly anti-iced with Type IV fluid. I also asked for a new start time with a full spraying of Type IV. I Contract de-icing company was attempting to de-ice the aircraft during the period when it was supposed to be applying anti-ice type IV. Contract Company not on the listed on Company NOTAMS of approved vendors. Maintenance was directed to coordinate the proper application of Type IV fluid; with the correct commencement of timing. Crew made visual checks of all surfaces to ensure they were free of ice/snow/contamination. Provide proper training/certification of vendor and its employees.