of Leeds
of Hounslow (1974)
c.1919 Public company incorporated[1]
1939 Managing Director John Goldwell Ambrose
1955 36th AGM. Maker of Bison precast concrete floors[2]
1962 Announced Bison system of construction of high rise flats using concrete panels[3]
1963 Acquired Concrete Development Co from Holland and Hannen and Cubitts[4]
1965 Appointed sub-contractors for industrialised building in construction of the University of Surrey[5]
1965 The company claimed to have built 2,200 dwellings using the Bison Wall Frame system, many more than most of the competing industrialised building systems[6]
1969 Acquired Banister, Walton and Co Ltd[7]
1970 Concrete tried to counteract the negative attitude towards system building following the collapse of the Ronan Point flats - released test data which showed the Bison system would be satisfactory provided the walls were properly tied into the structure[8]
1976 Concrete Ltd of Leeds acquired Dowsett Engineering Construction and subsequently Dowsett Piling and Foundations[9]
1977 Name changed to Bison Group. Concrete was acquired by National Chemical Industries of Saudi Arabia[10]
1978 Sold Dowsett Piling and Foundations to WGI Group[11]