The following text is from the original listed building designation:
LAMBERHURST FURNACE LANE TQ 6636-6736 (north side) 8/159 Furnace Mill, walls and outbuildings attached GV II
Mill, wall and outbuildings. C18, extended early C19. Timber framed and weather boarded with red brick on ground floor and with plain tiled roof, and extended with red brick. Two storey and garret mill building with half-hipped gambrel roof. Two 3 light wooden casements on first floor and central boarded loft door and 3 light casement to left on ground floor and 2 doubled cart doors to centre and to right. Lean-to outshot to right. Projecting from low in the left return side is the wheel axle, now in a dry wheel pit. The internal flooring and fittings for machinery survive, as do some elements of the machinery itself. Attached to right a single storey stable block with 3 strap hinged half-doors, and beyond that a red brick wall, about 6 feet in height and extending some 30 metres with a gateway, and linking to a red brick and tiled outhouse to the north of the main house. The site is one of great historical and archaeological importance, the Gloucester Furnace, the largest iron working furnace and mill in the Weald C17/C18 was located here; there are also earthwork remains in the vicinity and extending down the valley to Peppermills.
Listing NGR: TQ6614536131 (1)

The oasthouse and mill were subject to a historic building survey in 2018. Lamberhurst was a major centre of iron working from Roman times up to the industrial revolution and was the largest such centre in the Weald. Furnace Mill was itself once part of the Gloucester Furnace which reputedly made the railings for St Paul's Cathedral.

In 2018 the oast house was still well preserved although the drying floor had been lost (2)

<1> English Heritage, List of Buildings of Special Architectural or Historic Interest (Map). SKE16160.

<2> Archaeology South-East, 2018, Furnace Mill and Oasthouse, Hook Green, Lamberhurst, Kent, TN3 8LH, Historic building record (Unpublished document). SKE53330.