Cooker House At Acetone Factory, Former Royal Naval Cordite Factory

Cooker House at Acetone Factory, former Royal Naval Cordite Factory

This cooker house stands on the site of the acetone factory at Holton Heath, a former Royal Naval Cordite Factory. Built in 1916, it was converted into offices in the mid-1930s.

The building is a steel-framed structure clad in colourwashed brick with a corrugated iron roof, originally featuring a raised central clerestorey. The south gable end is fitted with a steel rolling door serving the central bay. The 11-bay side elevations contain timber casement windows with glazing bars to square panes. The east elevation includes a double-height doorway with mid-20th-century plank doors in the fourth bay from the left. A late-20th-century lean-to extension and tower have been added to the west elevation.

The interior was floored and converted into offices in the mid-20th century, except for the southernmost bays, which remain open to the roof. These bays clearly display the steel framework that originally supported an upper floor where ingredients were mashed before being gravity-fed into six cookers and then taken to adjacent fermentation vessels.

Historical Context

Holton Heath comprises the most significant explosives factory constructed for the British government during the First World War. The site was selected by the Admiralty in autumn 1914 and opened in January 1916, positioned advantageously near a railway and export routes to principal naval dockyards. The factory manufactured cordite for the Royal Navy's independent supply for shells, representing a marked departure from earlier gunpowder-based sites such as Waltham Abbey. Later explosives factories, including the Royal Naval Propellants Factory of 1938 at Caerwent in south Wales, benefitted from technological advances developed at Holton Heath.

The acetone factory represented the first purpose-built industrial plant in the UK designed for the application of biotechnology. Acetone was essential in the cordite manufacturing process to ensure gelatinisation of the principal ingredients. Wartime shortages prompted the Admiralty to adopt biotechnological production methods. Construction began in late 1916 or early 1917 under the direction of Chaim Weizmann, the future president of Israel, who had previously developed fermentation technology. Weizmann's bacterium could ferment starch sources directly to ethanol, butanol and acetone. Maize was initially imported from the United States, but during the peak of the U-boat campaign, alternative materials including artichokes, horse chestnuts and acorns were employed.

The acetone factory ceased production in the late 1920s and was partly demolished in 1934, leaving two important structures: the cooker house and a cluster of concrete fermentation vats, of which six out of the original eight survive. The plan form and internal features of the cooker house—particularly the steel frame with castings for load-bearing beams that carried the mash tuns—clearly relate to its original function and origin of world historical importance. Plants modelled on Holton Heath were subsequently built in Canada, the United States and India, incorporating elements borrowed from the brewing industry.

The neo-Georgian administrative and laboratory buildings to the north are listed grade II. The area around the cooker house, including vats, tramlines, the nitration plant and cordite press plant in the central area, and the cordite drying plant and picrite factory to the east, are Scheduled Ancient Monuments. Anti-aircraft sites and bombing decoy sites constructed for the site's protection during the Second World War are also subject to additional schedulings.