ONE of the oldest construction companies in York has begun work on a new city headquarters to cope with its massive growth.

William Birch and Sons Ltd, established in 1874, is to move out of its base in Foss Island Road which it built 18 years ago and into a building double the size at Osbaldwick next spring.

The new 11,000 sq ft three-storey steel-framed building is going up on land owned by the builder alongside its existing plant depot in Osbaldwick Link Road and the investment is reckoned to be worth about £1 million. It is also likely to open the door to more recruitment of office staff with 25 now on the payroll.

The modern headquarters it is vacating is up for sale and already agent Lawrence Hannah and Skelton of York reports big interest.

Now William Birch is also about to market nearly half an acre behind the Foss Islands Road building, including a 10,000 sq ft storage building for which it has just gained planning consent for a change of use to non-food retail.

But a decision is yet to be made on whether the land and building are for sale or lease.

The move comes during a huge growth spurt for the company whose turnover has rocketed from £7.5 million in 1999 to £12.5 million last year and is expected to reach between £15 million and £20 million this year.

David Holden, the firm's director of construction, said: "We needed to rationalise our building yard and head office on to one site.

"It should make us more efficient and it means we avoid the problems of inner ring road traffic while still having easy access to the city centre via the outer ring road."

Major projects due for completion this autumn include a £2.6 million English Heritage visitor centre in the ruins of the banqueting hall of Whitby Abbey; a £2 million transformation of an old school in Leeds into offices and an adult education centre; and a £1.2 million humanities block at Woldgate School, Pocklington, for East Riding of Yorkshire Council.

Its roofing and specialist work at Scampston Hall in Malton won the National Royal Institution of Chartered Surveyors' Awards 2000 and its Waterside development at Kirkstall Road in Leeds earned a Leeds City Council commendation.

Mr Holden said: "We are very positive about the future. The trade press are expecting recession but we can't see any signs of it."