Mendham had a mill in 1086, although the present building was constructed in 1807, and was extended in 1871, when a grasshopper beam engine was installed to supplement the water wheel, which only had a fall of , when water levels were low. The machinery was modernised in 1905, when the number of stones was reduced from nine to four, to make way for a roller plant. The beam engine was replaced in 1923, having been driven and maintained for over 50 years by Jimmy Souter. During this time it never broke down, and Souter died once it was dismantled. It was replaced by a Lister diesel engine, and then a Ruston and Hornsby engine. Part of the building was converted into a house in 1938, and the mill continued to operate until 1949. The rights to use the water were given up in the 1950s, in exchange for the provision of mains electricity to the premises. Both the mill and the house are grade II listed. There may also have been a paper mill at Mendham, but the evidence is inconclusive.