Formed over 25 years ago to manufacture double glazed windows and double glazed doors to the trade and independent companies in Doncaster and the surrounding areas. The company embarked on an expansion programme in 1994 that added 2 further factories and 13 trade depots to its portfolio, supplying high quality products nationwide. In 2005 the company opened its own "glass toughening plant" complete with furnace and the latest Willian production line.

The parent company, Armthorpe Glass Ltd began life in 1974 as a glass merchant but has now merged with Roundbrand and manufactures vacuum formed infill panels and double glazed sealed units. Both companies operate from the same 45,000 sq.ft freehold factory in Doncaster, South Yorkshire. Together they employ 80 people in a dedicated double glazing facility.