Harold was highly inventive, and always willing to develop new products. With the outbreak of the Second World War, he quickly switched the factory to wartime production, and developed specialist textiles for military applications. He also formed a new engineering division to produce aircraft parts.

Once the Second World War was over, the factory quickly returned to peacetime production. The engineering division was used to develop the new types of textile machinery that were required to handle new man-made fibres (such as nylon), that were gradually becoming available. While a new company, New House Fashions, was created to manufacture technical fabrics for industrial use.