THE Housing Department has appointed three private consultants to speed up the process of refurbishing vacant flats in public housing estates. The department had been doing the work since the scheme started, said Mr Robin Carpenter, assistant director of the maintenance division. But its staff resources were now ''stretched to the limit'', he said. Mr Carpenter said the department had taken on board a very large refurbishment programme. It was not just flats that were empty at the moment but also those that would become vacant in the normal course of events. The three consultants, Vigers, Chesterton Petty and Wayfoong, have been appointed to reinforce the existing maintenance team. Housing manager for lettings Mr Kok Siu-hang said his department had referred 6,330 flats for refurbishment since September last year. He said so far 1,231 had been completed. There was also another batch of 145 flats which had become vacant very recently to be referred for refurbishment in the next few days. ''Because of the large number of flats to be refurbished we can't complete them as quickly as we'd like, so we're appointing consultants,'' he said. The role of the three consultants is to look at Housing Department projects throughout the territory, liaise with housing managers to find out what work is needed, then issue a works order to the term contractor. Mr Shaun Eddleston, director of building consultancy at Vigers, said it was a three-month programme from start to finish. The Housing Department was handing out 300 flats a month to each consultant so that at any one time each consultant was handling 900 flats. There was a total of 2,700 flats at various stages of completion, he said. It would depend in each case on what work needed to be done: there were ''all types of flats in varying states of repair''. Generally, work was more concerned with finishes than structure of the buildings, he said.